Method having load-following power generation

Abstract

To provide a safer, more flexible, and more efficient load-following power generation method for generating, storing, and converting thermal energy. [Solution] The above method includes the steps of operating a nuclear reactor at full capacity, transferring the thermal energy from the nuclear reactor to the heat storage system, providing the thermal energy from the heat storage system to a power generation system, and generating power using the power generation system to follow the electrical load demand from the power grid.

Description

Detailed Description of the Invention

[0001] [Cross-Reference to Related Applications] This application claims the benefit of U.S. Provisional Application No. 62 / 833,623, filed Apr. 12, 2019, and U.S. Provisional Application No. 62 / 929,003, filed Oct. 31, 2019, under 35 U.S.C. § 119(e), both of which are entitled "NUCLEAR THERMAL PLANT by LOAD-FOLLOWING POWER GENERATION", the disclosures of which are incorporated herein by reference in their entireties.

[0002] [Background] The field of the present disclosure relates to nuclear reactors, and more particularly to nuclear reactors for generating heat having improved safety and load following capabilities.

[0003] Conventional methods and systems for generating power from nuclear reactors require that the nuclear reactor receive significant planning, construction, and regulatory approval of the nuclear island before startup. The nuclear reactor is connected to a power cycle for converting nuclear thermal energy into electricity, and is typically converted by a steam turbine that uses water as the working fluid. Although nuclear reactors operating in this manner have been around for decades, typical configurations have several drawbacks.

[0004] For example, a nuclear island, including a nuclear reactor area, a fuel handling system, and an energy conversion system, is typically operated at high temperature and high pressure, which requires a large containment structure. Additionally, the structures located in the nuclear island must also be inspected and given nuclear approval by regulatory authorities in order to operate, which is a long-term, costly endeavor.

[0005] Furthermore, nuclear reactors are subject to errors in the rest of the plant such that a malfunctioning device causes the automatic shutdown of the nuclear power plant. Finally, nuclear power plants are not designed for rapid changes in output and thus cannot efficiently follow the load demand from the power grid.

[0006] While nuclear power plants offer numerous and significant advantages over other forms of power generation, it is desirable that they provide safer, more flexible, and more efficient systems for generating, storing, and converting thermal energy, as well as improvements that will result in other features as will become apparent from the following description.

[0007] [Summary of the Invention] According to one embodiment, a nuclear power plant can be reconfigured, relocated, and operated as a nuclear thermal plant, offering numerous advantages. For example, a nuclear power plant can be reconfigured and operated to supply thermal energy, which can be transported to an off-site thermal storage system. The thermal storage system can then be coupled to an energy conversion plant that converts the thermal energy into industrial heat, electricity, or some other useful purpose. There are many advantages that can be realized by separating the reactor from the rest of the plant, including the energy conversion system.

[0008] For example, reducing the number of devices installed on a nuclear island would allow for much more efficient regulatory approval. In some reactors, the coolant is supplied by a liquid metal such as sodium. When sodium encounters water, the resulting reaction is exothermic and energetic, and safety systems must be in place to inhibit this reaction or contain it if it occurs. By placing the steam plant away from the reactor, the reactor is isolated from any water-containing systems that may be typically used in conjunction with a nuclear power plant.

[0009] In addition, multiple nuclear thermal plants can be coupled into a shared thermal storage system, which offers advantages in terms of cost and construction time, and also facilitates maintenance by allowing one or more reactors to be shut down without affecting the entire nuclear thermal plant. Furthermore, nuclear thermal plants can supply more energy more effectively during periods of high demand than when they are directly coupled to an energy conversion system.

[0010] The following description provides concepts that offer progressive possibilities for the economics of sodium reactor plants, as well as reactor plants using other fuels, coolants, and technologies. These advancements may arise from reimagining technologies that reduce cost and scheduling uncertainties, and from expanding revenue sources, such as supplying both electricity and heat to consumers. In addition to economic benefits, it may be possible to ensure the ability to address policy issues (such as grid reliability, weapons proliferation resistance, exportability, and ease of use in the field) and enable the realization of benefits.

[0011] [Brief explanation of the drawing] A better understanding of the features, advantages, and principles of this disclosure will be obtained by referring to the following detailed description, which describes exemplary embodiments, and the accompanying drawings.

[0012] Figure 1 shows a typical nuclear power plant.

[0013] Figure 2 shows a nuclear thermal plant separated from a power plant, according to one embodiment.

[0014] Figure 3 shows a nuclear thermal plant coupled to a thermal energy storage plant according to one embodiment.

[0015] Figure 4 shows a nuclear thermal plant coupled to a remote thermal storage plant having an optional auxiliary thermal storage plant, according to one embodiment.

[0016] Figure 5 shows a nuclear thermal plant coupled to a remote thermal storage system coupled to an external load, according to one embodiment.

[0017] Figure 6 shows exemplary industrial heating applications and required temperatures.

[0018] Figure 7 shows an energy system in which multiple heat sources share a common heat storage and energy conversion system, according to one embodiment.

[0019] Figure 8 shows an energy system, according to one embodiment, in which multiple heat sources share a common heat storage and energy conversion system with an auxiliary power system.

[0020] Figure 9 shows a nuclear thermal plant coupled to an external load, a remote heat storage system, and auxiliary heat utilization, according to one embodiment.

[0021] Figure 10 shows a hybrid energy system in which multiple forms of thermal energy generators are coupled to a common thermal storage system and a common power conversion system, according to one embodiment.

[0022] Figure 11 shows an energy system in which the nuclear power block is separated from the power block by an integrated energy storage block, according to one embodiment.

[0023] [Detailed explanation] The following detailed description will provide a better understanding of the features and advantages of the invention as described herein, in accordance with the embodiments disclosed herein. While the detailed description includes many specific embodiments, these are provided only as examples and should not be construed as limiting the scope of the invention disclosed herein.

[0024] While the cost of nuclear power is important and noteworthy, the revenue and policy aspects of nuclear power are equally worth focusing on. The cost of nuclear power is a crucial indicator in describing its commercial appeal, while also entering the highly regulated and commercialized market for base load power generation. Finding approaches that reduce the regulatory burden and broaden commercial market opportunities is key to progressive economic change that increases revenue for a moderate cost increase. Enabling technological solutions to policy issues also holds strategic value that is difficult to capture in considering nighttime construction costs. Leveraging currently undervalued attributes, such as zero CO2 emissions, along with the ability to integrate with an increasingly dynamic power grid, will become more valuable in the coming decades.

[0025] In addition to the issue of operating costs for load following by nuclear energy, since electricity prices vary daily, like those of "peaker" plants (e.g., power plants that can only be operated when there is high demand or peak demand), base load power generation does not have the ability to follow revenues. To improve the competitiveness of nuclear power generation in a changing energy environment, technological and process innovations are needed to enable nuclear power generation to operate at full capacity and access opportunities for market arbitrage (swing trading, arbitrage) in addition to full output power generation. When the production costs of intermittent renewable energy are below the electricity price, nuclear power plants require alternative production means to serve as an alternative to only the load-following electricity demand. This basically requires an understanding of the competitive advantages of nuclear power plants compared to intermittent renewable energy sources. These competitive advantages lead to the desire and opportunity for co-location with other industrial processes to achieve economies of concentration in energy production and manufacturing processes.

[0026] One of the characteristics of nuclear power compared to wind, solar, and other renewable energy sources is concentrated shaft power that precedes power generation and thermal output. Leveraging these differences can define a competitive advantage in low-cost energy production, either by more efficiently storing energy or by creating another marketable product. Many power plants rely on the steam Rankine cycle to convert thermal energy into electricity. While the conversion of shaft power to electricity in rotary generators is highly efficient (98-99%), the conversion from electricity back to shaft power is slightly less efficient (~95%). Further losses occur with boost voltage for transmission, transmission through transmission lines, and step-down voltage for local consumption. While the exact losses from transmission to consumption are location- and distance-dependent, the overall estimated loss from power generation to on-site consumption at a nuclear plant is estimated at 2-4% in this example. Combined efficiency losses show that direct shaft power has an efficiency gain of 8-11% compared to power generation to shaft power at a different location. As a result, there is a potential competitive advantage (strength) arbitrage opportunity between power generation and direct shaft-powered work with a sufficiently capable clutch and gear system. The clutch and gear system can convert shaft power entirely or partially to non-power generation work. The challenges lie in the application of start / stop up to the gigawatt scale and the mass flow rate of each product to support those enormous workloads.

[0027] One such example is to use a Compressed Air Energy Storage (CAES) or a Liquid Air Energy Storage (LAES) to supply the baseload power demand and, in addition, to supply shaft power for liquefying air, thereby enabling a nuclear power plant to operate at full capacity during periods of low electricity prices (and thus low power demand). The cryogenic liquefied air stored at atmospheric pressure can later be boiled with nuclear waste heat to drive a power generation turbine. CAES and LAES are estimated to scale to GW-hr scale storage and represent an important capability for power management. The stored liquefied air can then drive the turbine at peak power prices and avoid the nuclear from only baseload price determination. The scalability of CAES and LAES technologies and the technical maturity of large cryogenic storage tanks present an opportunity to combine the centralized shaft power and waste heat for cryogenic cooling of nuclear power to boil liquefied air and drive a turbine. This combination of capabilities is more effective than the electric drive pump requirements and "thermal energy storage" needs of currently proposed CAES and LAES technologies and gives the combined technology a competitive advantage compared to either technology alone. This technology can be retrofitted to the current U.S. nuclear fleet that produces 99 GW of electricity with appropriate development.

[0028] The most likely use of CAES and LAES is for energy production, but more selective distillation of liquefied compressed air can also provide high-quality gas streams as marketable products. As an example, it could be to sell a pure oxygen stream by temperature distillation for medical use or power generation for companies that wish to simplify carbon capture by removing the NOX and SOX problems by simply burning natural gas and oxygen. This opens the possibility of co-locating natural gas power plants with CAES nuclear power plants to simplify carbon sequestration. The remaining distilled gas could be supplied, for example, for their low temperature values, specific gas values, or consumed by wind turbines to generate power.

[0029] Another similar application of shaft power in the United States is the liquefied natural gas (LNG) export market, where demand continues to grow, reaching approximately 8.9 billion cubic feet per day by 2019. Currently, up to 10% of the supply gas for liquefaction is consumed in the process. Using more conservative estimates for a 4100 kJ / kg liquefaction process, approximately 230 GWh of energy is needed per year to support the current liquefaction process. Nuclear power plants can play a significant role in increasing LNG exports to other parts of the world through a combination of direct compression or CAES energy storage using chilled water CAES on one side of a heat exchanger and natural gas on the other. In this combined system, natural gas is liquefied for storage or export, and compressed air is boiled to drive an electric turbine. In either case, the air and natural gas can be brought into the power plant and processed easily, and are relatively well-suited for "start-and-shutdown" operations to accommodate load following.

[0030] Another example of fluid pump transport is hyperpumped-storage hydropower / aquifer renewal as a rational start / stop application. Assuming that market signals to guarantee large-scale pump transport (pumping, pressurizing) efforts and associated pipelines will develop in the next decade, the efficiency improvements using direct shaft power for aquifer renewal will amount to 7 quads per year (i.e., 1 quad = 10 quads). 15 BTU, i.e., 1.055 × 10⁻⁶ 18 It could exceed joules. While water recycling efforts would likely reduce the pumping effort required, they probably wouldn't eliminate the need for replacement water. Furthermore, these pumping efforts would also serve a massive "lifting" capacity, potentially running back along pipelines to replenish intermittent power and replenish regional aquifers.

[0031] As mentioned earlier, centralized shaft power is just one of the characteristics of nuclear power compared to solar, wind, and other renewable energy options. Industrial processes that produce refined oil, coke, steel, chemicals, cement, etc., require both energy and specific temperatures. This minimum temperature requirement for chemical processes to occur is a key differentiator in determining which primary energy source is best. While major heat consumption is specific to a single market, the temperature requirements for a given process are universally necessary. Processes have a spectrum of temperature requirements, but the main interesting temperatures appear to be 100-250°C, with steam and hot water production, refining (petrochemical) processes in the 250-550°C range, and high-temperature processes for cement, steel, and glass production exceeding 1000°C. Looking at the overall energy market, oil refining consumes more than 6 quads per year, and forest products consume just over 3 quads per year.

[0032] Fossil fuels currently meet both the scale and temperature of energy demand. In a decarbonized energy world, the challenge lies in finding the best alternatives to the utility and versatility of fossil fuels. Wind, solar, and hydropower generate substantial amounts of energy, but not substantial amounts of high-quality heat. These energy sources must undergo further energy conversion to produce higher-quality process heat. Pricing for these energy sources must include additional processes, such as hydrogen production using resistance heaters or blast furnaces. Additional energy storage requirements may exist to achieve high capacity utilization rates for operating industrial equipment 24 hours a day, or to accept "loss of opportunity" in low-capacity plants.

[0033] Nuclear power plants have competed on price by competing with heat rather than electricity, based on $ / kWe converted to the required temperature relative to the temperature $ / mmBtu. One of the most obvious starting points of competition is the direct generation and consumption of steam. Forest products consume 1.3 quads of steam per year, which is equivalent to more than 45 GWth of a nuclear power plant running 24 hours a day simply for process steam. In the production of forest products, part of the process generates waste such as black liquor (e.g., waste from the kraft process when digesting pulp to make paper pulp and removing lignin, hemicellulose and other extracts from wood to remove cellulose fibers), biomass and other residual fuels, which are burned to generate steam for process heating. The remainder of the required fuel is currently supplemented by coal or natural gas. By utilizing nuclear power for steam, 1330 TBtu (1.3 quads) of major energy used for other high-temperature applications such as petroleum refining and cement applications would be freed up. By utilizing nuclear thermal energy to provide high-quality process heat to forestry, the recovered forest product energy, combined with reserve energy, could meet the energy requirements (combined less than 1 quad) for both cement and glass manufacturing in the United States. The combustion of forest products is considered carbon-neutral active and therefore allows for nuclear substitution of steam generation to directly support high-temperature processes. While there is considerable flexibility in fuel sources for cement manufacturing, technological innovation will be needed to ensure that forestry fuel products can be transported and used for other major thermal applications. Similar to forest products, the chemical manufacturing industry as a whole consumes 1.2 quads of steam, which could be directly replaced by steam generated by nuclear power. However, this energy displacement does not completely liberate renewable fuel sources, but simply reduces the amount of natural gas and coal needed to drive processes, and even in this case, renewable energy would also be burned to support its conversion into products.

[0034] Another use of steam from nuclear power involves a combination of nuclear plants producing steam for hydrogen electrolysis while intermittent power sources generate cheap electricity, and electricity when the intermittent power sources are off. As the steam temperature increases, the electricity required for electrolysis decreases. However, the increased power efficiency at higher temperatures may not be economically interesting in a world where intermittent power generation during peak hours brings electricity costs down to "meter-level cheap." If the cost of electrolysis equipment can be cheaply integrated into a steam bypass pipeline, reactors could easily switch to electrolysis, partially or entirely, during periods of cheap electricity. This would allow nuclear plants to compete for heat production during periods of low electricity prices and for electricity during periods of high electricity prices. The resulting hydrogen production should be viewed not only as an energy storage mechanism but also as a source of heat for industries requiring temperatures above 1000°C, such as cement, iron, steel, and glass.

[0035] For advanced reactors with higher outlet temperatures, more direct industrial process opportunities become available. For example, higher reactor outlet temperatures can be used as preheaters for other industrial processes or as a primary heat source for chemical processes. In petroleum refining, there is a significant energy demand in hydrocarbon distillation and cracking, which require more than 6 quads of energy. Sodium-cooled reactors can be the primary heat source for numerous cryogenic cracking processes, and the reactor heat can also be "heated up" to the required peak refinery temperature using electric heating or small amounts of fossil fuels. Many of the technical challenges in this case are establishing refinery technologies that accept temperature and energy inputs other than petroleum, electricity, and steam, as well as minimizing the number of heat exchangers / loss values ​​during heat exchange. One example would be a replacement for the salt / oil heat exchanger for traditional combustion boxes for high-temperature cracking. Other types of advanced reactors, such as molten salt reactors, can be used to directly generate the required high-temperature industrial process heat, for example.

[0036] Furthermore, there is an opportunity for heat storage to separate heat production from heat utilization in nuclear thermal plants. It has been proposed to heat large heat accumulators using the primary coolant of the nuclear thermal plant, for example, as a phase-change salt, and pump the heated salt into large tanks. These large tanks of heated salt can then be used to generate electricity by a steam Rankine cycle or to supply process heat for coating bases. By separating heat generation from its direct utilization, the heat accumulator serves as a flexible means of "load following" electricity generation by operating at full power and filling high-temperature saltwater tanks, but generating electricity when it is more valuable, such as during peak demand or more traditional base load energy generation. This approach also allows nuclear power plants to operate like Pika plants for price arbitrage opportunities, while still operating at full power. Additional cost savings also exist if nuclear power plants and primary coolant / salt heat exchangers and salt storage facilities can be separated as non-critical to the safety of the reactor, thereby subjecting construction and equipment regulations for power generation to the same standards as non-nuclear power plants. This enables typical commercial security protocols, operating and maintenance costs ("O&M"), and quality standards, which can justify any heat exchanger or heat loss by pumping hot salt out of the safe zone of the nuclear power plant. Essentially, power systems for nuclear power plants can be built in non-NQA1 environments (with associated maintenance work) to obtain commercially competitive structures from existing solar thermosalt power companies.

[0037] Higher-temperature reactors, such as sodium-cooled, molten salt, and high-temperature gas reactors, can also participate in hydrogen production using processes different from wind and solar energy, in addition to the steam-electrolysis discussed earlier. One example of a high-temperature process is the copper-chlorine cycle. This cycle uses process heat at 400-500°C to produce hydrogen and oxygen gases. The final stage of the cycle recirculates all chemicals except water, which is converted into gas, using ambient-temperature electrolysis. This process presents an interesting opportunity to "supply-follow" the inexpensive electricity generated during peak wind and solar periods. The plant equipment and O&M costs are justified by running a higher-temperature nuclear thermal plant nonstop to produce hydrogen and oxygen gases, while filling tanks with copper-chlorine reactants for electrolysis. When electricity becomes inexpensive, ambient-temperature electrolysis is used to return the tanks to the appropriate chemical precursors, restarting the cycle. This process is spiritually similar to filling salt tanks with thermos salts for later use, but more specifically tailored to the final chemical product. While this example does not necessarily advocate for the copper-chlorine cycle, the idea of ​​power supply tracking is a different approach from energy storage to track demand. Furthermore, this process would allow most of the equipment used in nuclear power plants for hydrogen production to be used only in certain tanks and electrolysis units that are idle during normal operation.

[0038] These features and benefits, like many others, can be realized by relocating nuclear power plants, which would allow for the co-location of nuclear thermal plants with industrial and chemical thermal applications, reduce the footprint of NQA1 certified areas, and enable load-following capabilities while operating reactors at full power.

[0039] Referring to Figure 1, a typical nuclear power plant 100 is shown. The layout of the nuclear power plant 100 includes two main parts: a nuclear island and a turbine island. The nuclear island has a reactor area 102 at its center that houses the reactor. The fuel handling area 104 is adjacent to the reactor area, and both buildings are usually located within a containment area 106. The containment area 106 may include a containment enclosure structure, which can be made of reinforced steel, concrete, or lead, or a combination of materials that form the enclosing structure that houses the reactor. Its design and function is to contain leaking radioactive steam or gas, and is often designed to contain gas leaking at pressures of 550 kPa or higher. The containment structure is designed as the last line of defense to withstand a design basis accident. The cost of constructing the containment structure is not only directly proportional to the size of the reactor, but also based on the remaining systems of the plant and the components that need to be housed within them. The nuclear island also includes auxiliary components such as pumps, fluid loops, control rooms, and other supporting components.

[0040] The fuel handling area 104, which may be located within the containment area 106, is designed to provide refueling capacity at a rate that maintains continuous reactor operation. The fuel handling area 104 also contains subcritical fuel outside the reactor core, preventing fuel damage and contamination. Furthermore, the fuel handling area 104 may include equipment for moving fuel pins and fuel assemblies, such as for reloading fuel into the reactor core.

[0041] A steam generator 108 is coupled to the reactor area and parts of the nuclear island. In some cases, the steam generator 108 is located within a containment area 106 and supplies superheated steam to a steam turbine 110. The steam generator 108 receives thermal output from the reactor and transfers thermal energy to the steam turbine 110, which converts the steam energy into mechanical energy. In some facilities, radioactive water passes through the steam turbine 110 but must be kept within a radiologically controlled area of ​​the nuclear power plant. The steam turbine 110 is then mechanically coupled to a generator 112, which converts the mechanical energy from the steam turbine 110 into electricity.

[0042] A fuel pin inspection area 114 may be located on-site for conducting post-irradiation inspection ("PIE") and analysis. The fuel pin inspection area 114 is often adjacent to a fuel handling area 104 to share competitive fuel handling equipment. The fuel pin inspection area 114 may further include a hot cell for accumulating and inspecting irradiated fuel pins.

[0043] As shown in Figure 1, the containment area 106 may be required to encompass the reactor area 102, as well as the fuel handling area 104. In some cases, the building of the steam generator 108 and its associated equipment are outside the containment area 106, but in many cases, they are required to be inside the containment area 106. One or more coolant loops are used to transfer heat from the reactor area 102 to a cooling fluid via heat exchangers, which not only cools the reactor core but also transports heat from outside the containment area to the building of the steam generator 108. Often, the primary coolant loop receives heat from the reactor core via a primary heat exchanger and transfers the thermal energy to the secondary coolant loop via a secondary heat exchanger. Often, the coolant in the primary coolant loop is radioactive. Many reactors currently in use rely on water under pressure as both a coolant and a neutron moderator. The primary coolant typically undergoes a phase change from liquid to steam as it absorbs thermal energy from the reactor core and then transfers that thermal energy to the secondary loop.

[0044] The coolant in the secondary loop, which may be water, receives heat from the primary coolant loop and undergoes a phase change from liquid to steam, which is used to drive the steam generator. This superheated steam is typically under high pressure, which requires that safety measures be in place to contain the high-pressure and high-temperature steam in case of failure.

[0045] In some examples, the primary and / or secondary coolant may be another material, such as molten metal. For example, in some fast reactors, molten metals such as liquid sodium are used as coolants. In other examples, molten salts may be used as coolants. Both molten metals and molten salts have low vapor pressures even at high temperatures and are therefore capable of transferring heat at pressures lower than those at which water is possible at similar temperatures.

[0046] A nuclear power plant 100 is typically protected by a site boundary 120, which may include a security boundary such as a tall fence with laser wires. The nuclear power plant 100 and its associated buildings, structures, systems, pipes, etc., can be referred to as the reactor site, which is located within the reactor site boundary 120. Among other measures, additional security measures such as gates at all access points, guards at access points, surveillance cameras, motion detectors, and / or electrified fences are typically used to protect the reactor site.

[0047] Nuclear power plants are also required to have an Emergency Planning Zone ("EPZ") necessary to prepare for a major accident at the nuclear power plant. In many cases, the EPZ will encompass a radius of 10 miles from the nuclear power plant.

[0048] As shown in Figure 2, the reactor area 202 and the fuel handling area 204 are located within a containment area 206 containing a containment structure. These two main buildings, along with the control room, constitute the nuclear island. Compared to the typical nuclear power plant shown in Figure 1, it can be seen that the steam generators, steam turbines, generators, and fuel pin inspection area are no longer on the nuclear island. Rather, these components are installed away from the nuclear island. The illustrated reactor area 202 is configured as a nuclear thermal plant 200, designed and operated to generate heat (as opposed to electricity in a typical nuclear power plant). In the illustrated configuration, the thermal storage system 208 is located away from the nuclear island and receives thermal energy from the nuclear thermal plant 200. Note that the thermal energy generated by the nuclear thermal plant 200 is transported away from the nuclear island, often beyond the site boundary 210, and even beyond the EPZ.

[0049] One direct advantage of this configuration is that the thermal storage 208 and power generation 212 facilities are outside the scope of nuclear regulations. This allows the nuclear thermal plant 200 to be constructed and licensed far more efficiently than would be possible with the installation of a nuclear power plant.

[0050] The reactor shown in Figure 2 may be any suitable type of reactor. For example, the reactor may include, but is not limited to, a thermal-spectrum reactor, a fast-spectrum reactor, a multispectrum reactor, a breeder reactor, or a traveling-wave reactor. The thermal energy generated by the reactor can be transferred to a heat storage system using the energy transfer system 214.

[0051] In some embodiments, a reactor can utilize fuel that does not require heavy equipment for handling the fuel, such as for reloading fuel pins or refueling the reactor. Therefore, in these embodiments, the fuel handling area 204 may be much smaller than that required for moving fuel pins and fuel assemblies in and out of the reactor core. Such reactors may include, among other things, pool reactors or molten salt reactors. One advantage of this type of reactor is that the fuel handling area 204 may be much smaller, and therefore the nuclear island and / or containment area 206 may be smaller than that typically required by reactors utilizing fuel pins and fuel assemblies, and thus require heavy equipment for their handling and operation.

[0052] In some embodiments, the reactor may include a reactor having a liquid coolant. For example, the liquid coolant of the reactor may include, but is not limited to, a liquid metal or salt coolant (e.g., uranium chloride, uranium trichloride, uranium tetrachloride, lithium fluoride, beryllium fluoride, or other chloride or fluoride salts), a liquid metal coolant (e.g., sodium, NaK, other sodium alloys, lead, or lead-bismuth), a liquid organic coolant (e.g., diphenyl with diphenyl oxide), or a liquid water coolant.

[0053] In another embodiment, the reactor may include a reactor having a pressurized gas coolant. For example, the pressurized gas coolant may include, but is not limited to, pressurized helium gas or pressurized carbon dioxide gas.

[0054] In another embodiment, the reactor may include a reactor having a mixed-phase coolant. For example, the mixed-phase coolant may include, but is not limited to, a gas-liquid mixed-phase substance (e.g., water vapor-liquid water).

[0055] The thermal storage system 208 may include any suitable thermal storage plant, whether currently known or to be developed later. In one embodiment, the thermal storage system can store thermal energy in the range of 500°C or higher. In one example, the thermal storage system stores energy at 550°C, 600°C, 700°C, and 750°C or higher. In one example, the thermal storage system 208 is designed to store thermal energy at 1000°C or higher. In one embodiment, the thermal storage system 208 has multiple thermal storage bodies that store thermal energy at different temperatures.

[0056] The thermal storage system 208 is thermally connected to the reactor by an energy transfer system 214. The energy transfer system 214 receives thermal energy from the primary heat exchanger associated with the reactor. For example, the reactor primary coolant passes through the primary heat exchanger, transferring thermal energy from the reactor core to the energy transfer system 214, thus cooling the primary coolant and transferring thermal energy to the energy transfer system 214. The energy transfer system 214 can be considered a secondary coolant loop designed to receive thermal energy from the primary coolant loop and transport that thermal energy to the thermal storage system 208.

[0057] For example, the first part of the energy transfer system 214 may be in thermal communication with a part of the primary coolant loop of the reactor, and the second part of the energy transfer system 214 may be in thermal communication with the heat storage system 208.

[0058] Those skilled in the art will recognize that a combination of heat exchange loops, heat exchangers, and heat pipes may be used to supply heat from the reactor to the energy transfer system 214 and to the thermal storage system 208. For example, the primary heat exchange loop of the reactor can be thermally coupled to the energy transfer system 214 using a primary heat exchanger containing a number of heat pipes. Alternatively, the energy transfer system 214 can be thermally coupled to the thermal storage system 208 using a second heat exchanger that can also contain a number of heat pipes. In this way, the thermal energy generated by the reactor can be transferred to the thermal storage system 208. The energy transfer system 214 may utilize a liquid metal, salt, or some other working fluid to facilitate heat transport. Alternatively, the energy transfer system 214 may be in direct thermal communication with the storage medium of the thermal storage system 208, such as at a location where the storage medium can move from the thermal storage system 208 and enter the first heat exchanger in the reactor vessel.

[0059] The power generation system 212 is downstream of the thermal storage system and can be thermally connected to the thermal storage system 208. The result of this type of configuration is that the nuclear island is isolated from the power generation system 212. In other words, a failure occurring in the equipment associated with the power generation system 212 or the thermal storage system 208 will not immediately affect the reactor. In traditional reactor systems, failures in equipment associated with the power generation system 212 often cause an automatic and immediate shutdown of the reactor core. This is generally provided as a safety feature to avoid problems caused by excess heat generation without sufficient heat transfer capacity to remove excess heat from the reactor system.

[0060] In some cases, the thermal storage system 208 has a greater thermal energy capacity than the thermal power output of the reactor is designed to produce. For example, the thermal storage system 208 may be designed to supply 1200 MWth of energy, while the reactor may be designed and operated to output 400 MWth of energy. This allows the thermal storage system 208 to store surplus energy beyond what the reactor supplies and to supply this energy to the power plant 212 as needed. For example, when the load demand to the thermal storage system 208 is lower than the output of the reactor, the thermal storage system 208 is charged with additional thermal energy. During periods of high demand when the load demand to the thermal storage system 208 is greater than the output of the reactor, the thermal storage system 208 is discharged.

[0061] As further shown in Figure 2, a power plant 212 is coupled to the thermal storage system 208. The power plant 212 can be any power plant 212 that is currently known or will be developed later. In one embodiment, the power plant 212 receives thermal energy from the thermal storage system 208 and converts the thermal energy into electricity.

[0062] In some cases, thermal energy can be passed through a steam generator to produce high-temperature, high-pressure steam, which can then be used to drive a steam turbine. The steam turbine, in turn, drives a generator, which converts the mechanical work of the steam turbine into electricity, which, as is well known, can be supplied to the power grid.

[0063] In another example, thermal energy from the thermal storage system 208 can be sent to a solid-state power generator that directly converts heat into electricity without requiring the generation of steam or the conversion of thermal energy into mechanical work. Such systems are currently under development, and the disclosed embodiments are well suited to be coupled to future power plants that require heat for power generation.

[0064] The thermal storage system 208 is thermally connected to the power generation system 212 by any suitable means. For example, an energy supply system 216 can be provided to supply thermal energy from the thermal storage system 208 to the power generation system 212. For example, the energy supply system 216 may include a fluid loop having a first part that is thermally connected to the thermal storage system 208 by a heat exchanger or the like, and a second part that is thermally connected to the power generation system 212 by another heat exchanger or the like. The heat exchanger may be any suitable heat exchanger, but is not limited to, a shell-and-tube heat exchanger, a double-pipe heat exchanger, a plate heat exchanger, a condenser, an evaporator, a boiler, or a combination of one or more different types of heat exchangers.

[0065] The illustrated configuration and application of the thermal storage system 208 allow the reactor to be isolated from power conversion applications. This offers several advantages. For example, the reactor is no longer affected by transient events from outside the site boundary 210 that could cause errors in the rest of the plant. These types of malfunctions can be handled without the need to shut down the reactor. In conventional nuclear power plants, plant transient events lead to reactor errors, which are economic and safety concerns. These transient events can be caused by malfunctions in the rest of the plant's systems, such as malfunctioning components in the steam generator, steam turbine, or some other auxiliary components, which can shut down the reactor. With respect to the nuclear thermal plant 200, these issues are no longer a concern because the reactor is isolated from the rest of the plant's systems. The power generation system 212, the thermal storage system 208, or the reactor system can all be safely shut down for maintenance, etc., without affecting other systems.

[0066] For example, the reactor system can be shut down and taken offline while the thermal storage system 208 continues to supply thermal energy to the power generation system 212, which continues to supply electricity. Similarly, the power generation system 212 can be shut down or operated at reduced output while the reactor system continues to generate thermal energy and essentially continues to charge the thermal storage system 208 with heat. In one embodiment, the reactor system is operated at full capacity, and thermal energy is transferred to the thermal storage system 208, which is completely independent of the load on the power generation system 212. The load on the power generation system 212 tends to fluctuate throughout the day, week, month, and season, while the reactor system can operate continuously at full capacity regardless of the load.

[0067] Furthermore, in nuclear thermal plants utilizing sodium-cooled reactors, safety is increased because, as explained, moving the steam generation system to a remote location eliminates little to no risk of water from the steam cycle interacting with the sodium used in the reactor.

[0068] In traditional nuclear power plants, the intercoolant loop transfers thermal energy from the reactor's primary coolant loop to the steam generator and, being close to the reactor core, is exposed to radiation of this type, which degrades the construction materials. For example, certain metals can become brittle due to radiation hardening, which reduces their toughness and makes them susceptible to brittle fracture. In the configuration described, the intercoolant loop is moved away from the reactor (or eliminated entirely), and this intercoolant loop can be made of materials that are easier to supply and manufacture, and therefore cheaper and more readily available.

[0069] As illustrated, the thermal storage system 208 and the power generation system 212 are located outside the site boundary 210 of the nuclear thermal plant 200. Specifically, the nuclear thermal plant 200 is located within the site boundary 210, such as a protective fence, and all equipment within the site boundary is subject to strict nuclear regulations. If the rest of the plant's systems, such as the thermal storage system 208 and the power generation system 212, are located far outside the site boundary 210, the regulations on these systems are significantly reduced, making construction, licensing, and operation much more efficient. These remaining plant systems may also be located outside the EPZ.

[0070] In one embodiment, the nuclear thermal plant 200 may include an intrinsically safe reactor, and the EPZ may be sized to coincide with the site boundary 210. In other examples, the EPZ may be sized to lie within the site boundary 210. In either case, locating the rest of the plant system outside the reactor site boundary 210 offers numerous advantages in terms of safety, efficiency, and speed of construction and licensing.

[0071] Furthermore, in the described configuration, the nuclear thermal plant 200 is load-following. Load following is the concept of adjusting power output as electricity demand fluctuates throughout the day. Traditional nuclear power plants typically operate at full output at all times and generally do not fluctuate their output power. In the described configuration, the nuclear thermal plant 200 can operate at full output, which can be designed to meet the base load requirements of the power grid. The base load of the power grid is the minimum level of demand over a period of time. This demand can be met by continuous power plants, rapid-fire power plants (e.g., for on-demand power systems), a collection of smaller intermittent energy sources, or a combination of energy sources. The remainder of the demand fluctuates throughout the day and can be met by rapid-fire power plants that can be quickly turned up or down, such as load-following power plants, peaking power plants, or energy storage.

[0072] The thermal energy output from the nuclear thermal plant 200 is stored in the thermal storage system 208 and supplied to the power generation system 212 as needed. In other words, the nuclear thermal plant 200 can charge its thermal storage at a nearly constant rate, and the thermal storage system 208 can supply thermal energy to the power generation system 212 to generate power that follows the electrical load demand from the power grid. Therefore, the nuclear thermal plant 200 can not only meet the base load requirements but also provide load-following capability while operating continuously at full or near full output.

[0073] Furthermore, the thermal storage system can be larger than the size configured to be supplied by the nuclear thermal plant 200, so that the nuclear thermal plant 200 can "charge" the thermal storage system during periods of non-peak electricity demand. In many load-following power plants, the plant operates between day and night, directly responding to changing power demands. The power plant can shut down in the evening or at night when demand is low and then restart as demand increases during the day. In the configuration described, the nuclear thermal plant 200 can operate continuously, and the thermal energy generated can be stored until needed for power generation or for some other purpose. In some examples, the nuclear thermal plant 200 may generate less thermal energy than needed to meet peak load demand, but can charge the thermal storage system during non-peak usage times, so that the overall energy output from the nuclear thermal plant 200 can supply base load and peak load demands over time.

[0074] In another example, the nuclear thermal plant 200 can produce more energy than is needed to meet base load demand. For instance, the nuclear thermal plant 200 can produce enough thermal energy to meet base load demand, plus surplus thermal energy to meet peak load demand, and also supply additional thermal energy for other industrial purposes.

[0075] Referring to Figure 3, a nuclear thermal plant 200 including a thermogenerating reactor 302 is shown. The reactor 302 is thermally connected to a thermal storage system 304. The thermal storage system 304 is thermally connected to an energy conversion system 306 which is connected to an external load 308.

[0076] The thermogenerative reactor 302 can be any suitable type of reactor currently known or to be developed in the future, such as a fission reactor or a fusion reactor. Such suitable reactors include, but are not limited to, fast neutron reactors, thermal neutron reactors, heavy water reactors, light water moderated reactors, molten salt reactors, liquid metal cooled reactors, organic moderated reactors, water-cooled reactors, gas-cooled reactors, and breeder burn reactors. Furthermore, the thermogenerative reactor 302 can comprise any suitable size reactor, such as a small modular reactor, a micro-reactor, or even a gigawatt-sized reactor or larger. Additionally, one or more reactors (which may be of the same type or different types and sizes) may be utilized in an integrated energy conversion system.

[0077] The reactor site boundary 310 is a physical barrier surrounding the nuclear thermal plant 200 and is designed to secure the reactor 302. Often, the site boundary 310 surrounds a nuclear island, which can be much smaller than a typical nuclear thermal plant, as described above in conjunction with the embodiments described above. The thermal storage system 304 is located outside the reactor site boundary 310. As described, the thermal storage system 304 can be any suitable type of thermal storage system 304 and any suitable type of thermal storage medium can be used. For example, the thermal storage medium may be a eutectic solution, a phase change material, a miscible gap alloy, or a mixture of metals (e.g., AlSi 12This may include cement-based materials, molten salts (e.g., chloride salts, sodium nitrate, potassium nitrate, calcium nitrate, NaKMg, or NaKMg-Cl), solid or molten silicon, or combinations thereof or other materials.

[0078] In some examples, the heat storage medium is also used as the heat transfer fluid in the energy transfer system 312 and / or the energy supply system 314. In this way, the energy transfer system 312 may be in fluid communication with the energy conversion system 306, and the heat transfer fluid of the energy transfer system 312 may directly interact with the heat storage medium of the heat storage system 304. Similarly, in some examples, the energy supply system 314 may use the same heat transfer fluid as the heat storage medium of the heat storage system 304. In some cases, the heat storage system 304 may be in direct fluid contact with the energy supply system 314.

[0079] The thermal storage system 304 is thermally connected to the reactor 302 by an energy transfer system 312, which can be thermally coupled to the reactor 302 by a heat exchanger. The energy transfer system 312 typically transfers thermal energy to the thermal storage system 304 via an insulated conduit, where the thermal energy is stored until needed.

[0080] The thermal storage system 304 is thermally connected to the energy conversion system 306 by an energy supply system 314, etc. The energy conversion system 306 may be any suitable type of currently known or later developed technology that can convert thermal energy into another form of useful energy. In one example, the energy conversion system 306 uses a steam turbine that may operate in a Rankine cycle to convert steam into mechanical work. Often, the steam is sent through a steam turbine that rotates the shaft of a generator to produce electricity.

[0081] The energy supply system 314 can be any suitable combination of heat transfer devices. In some cases, one or more heat exchangers are associated with the thermal storage system 304 and the energy conversion system 306, respectively. The working fluid located within the energy supply system 314 (such as a fluid loop) receives thermal energy from the thermal storage system 304 in one or more heat exchangers associated with the thermal storage system 304 and supplies thermal energy to the energy conversion system 306 in one or more heat exchangers associated with the energy conversion system. The energy supply system 314 can use any suitable working fluid as described herein.

[0082] The energy conversion system 306 can be coupled to an external load 308 by an energy transmission system 316. The external load may be the public power grid. The energy conversion system 306 can send the generated electricity to the power grid by high-voltage transmission lines, etc., which carry the electricity from the energy conversion system to the demand center. In particular, the energy conversion system 306 is located away from the reactor 302, often outside the reactor site boundary 310, and often outside the EPZ as well. As described, the reactor 302 is isolated from the energy conversion system 306, and any failure in the energy conversion system 306 will not negatively affect the reactor 302, nor will it have a negative impact on the reactor 302. In fact, even if the reactor 302 is shut down, for example for maintenance or refueling, the thermal storage system 304 can continue to supply thermal energy to the energy conversion system 306 in order to supply power to the external load.

[0083] The relatively low cost of the thermal storage system 304 for the nuclear thermal plant 200 is advantageous for scaling up the thermal storage system 304 and scaling down the nuclear thermal plant 200. Furthermore, when low-pressure heat transport (e.g., molten salt as a heat transport medium) is used, the relatively high-cost energy converter 306 can be installed remotely from the nuclear thermal plant 200, in which case the converter can be constructed more efficiently and without the restrictions that would be necessary if it were built on the reactor site. As used in this disclosure, the term “low pressure” is used to refer to a pressure of less than approximately 3.5 MPa.

[0084] In addition, if there is no high-pressure system coupled to the reactor 302 (e.g., exceeding approximately 3.5 MPa), the EPZ can be minimized and the heat transport distance can be shortened. In some examples, the thermal storage system 304 may be installed in a location adjacent to the reactor site but outside the site boundary 310. This minimizes the heat transport distance while keeping the thermal storage system 304 and the energy conversion system 306 outside the reactor site boundary 310 and outside the scope of nuclear regulations.

[0085] Referring to Figure 4, the reactor 302 may be similar to the reactor in Figure 3, and may be coupled to the thermal storage system 304, which may be substantially similar to the thermal storage system 304 in Figure 3. The reactor 302 may also be coupled to an auxiliary thermal storage system 402. In some examples, the thermal storage system 304 may optionally be thermally coupled to the auxiliary thermal storage system 402. The reactor 302 can be configured to transport thermal energy to the thermal storage system 304, the auxiliary thermal storage system 402, or both.

[0086] The heat storage system 304 is coupled to the energy conversion system 306, as described herein. The energy conversion system 306 is coupled to an external load 308, which may be any load such as an electrical load or a thermal load.

[0087] The auxiliary heat storage system 402 may be located outside the reactor site boundary 310 as shown in the figure, and in some cases, it may be located inside the reactor site boundary 310. In one embodiment, its function is to control the return to the reactor 302 and the core inlet fluid temperature. in T is expected to in If there is a difference between the expected and actual temperatures, the reactor control system may initiate changes to the reactivity to compensate for the temperature difference. For example, if the core inlet temperature is higher than expected, the reactor control system may reduce the reactivity to compensate for the higher-than-expected inlet temperature.

[0088] The auxiliary heat storage 402 may be dedicated to the reactor and may be used to control and / or stabilize the core inlet temperature. For example, the auxiliary heat storage 402 can be in thermal communication with the primary coolant loop in the reactor vessel. The primary coolant fluid is expected to reach T in When the primary coolant has a different temperature, the auxiliary heat storage 402 can interact with the primary coolant loop to add or remove heat from the primary coolant. When the primary coolant interacts with the working fluid of the auxiliary heat storage, the effect is that the primary coolant reaches thermal equilibrium with the auxiliary heat storage fluid. By controlling the primary coolant temperature, the reactivity within the reactor core is stabilized and any spontaneous fluctuations are smoothed out.

[0089] In one example, the auxiliary thermal storage system 402 is in direct thermal communication with the reactor 302 by transferring a portion of the reactor's thermal energy to the auxiliary thermal storage system 402. In another example, the auxiliary thermal storage system 402 is in thermal communication with the thermal storage system 304, and a portion of the thermal energy from the thermal storage system 304 is transferred to the auxiliary thermal storage system 402 for use in adjusting the reactor core inlet temperature.

[0090] Those skilled in the art will readily understand how to connect these various systems to one another through thermal communication and how to use these systems to regulate the core inlet temperature.

[0091] Referring to Figure 5, a nuclear thermal plant 500 is shown that is substantially as described above. In particular, some reactor designs do not require reliance on heavy fuel assembly handling equipment. For example, in pool reactors such as molten salt reactors, there are no fuel pins or fuel assemblies that need to be stored, moved, inserted, or removed from the reactor core. As a result, the fuel handling area 204 can be significantly smaller than that of a traditional nuclear power plant. Furthermore, many reactor designs that rely on diffusion-tolerant fuel cycles, such as breeder and burn reactors or molten salt reactors, do not require a fuel handling area within the containment area. In these embodiments, the containment area 206 may be much smaller and may contain only the reactor and smaller subsystems of the reactor. This results in a significantly smaller containment area 206, which leads to lower costs for construction, licensing, and operation.

[0092] In addition, a smaller containment area 206 results in a smaller footprint for the site boundary 310. Furthermore, in an inherently safe reactor design, the site boundary 210 can be minimized, and the EPZ can also be minimized. In some cases, the EPZ boundary coincides with the reactor site boundary 210, or in some cases, the EPZ is within the site boundary 210. This allows the heat storage system 208 and / or the power generation system 212 to be located outside the site boundary 210, while being located relatively close to the site boundary 210, thereby reducing the heat transfer distance of the energy transfer system 214.

[0093] As shown in the figure, the thermal storage system 208 may be in thermal communication with one or more loads 510. For example, the thermal storage system 208 can, among other things, supply thermal energy for industrial heating 512, district heating 514, or power generation 212.

[0094] The applications of industrial heat 512 are diverse and require heat at various temperatures. Industrial heat applications can include fluid heating for food preparation, chemical product manufacturing, reforming, distillation, and hydrogenation, requiring temperatures in the range of approximately 110°C to approximately 460°C. Similarly, curing and forming processes for coating, polymer manufacturing, enamel, extrusion, etc., require heat in the range of approximately 140°C to approximately 650°C. Other processes include iron formation, smelting, and steelmaking, as well as the manufacture of plastics and rubber. This industrial heat can be supplied by the heat storage system 208 as needed, in the quality and quantity required for the specific industrial heat 512.

[0095] District heating 514 is a distribution system for supplying heat from a central heat source through a system of insulated pipes, such as for commercial and residential heating applications (e.g., local heating and hot water). This heat is generally in a lower temperature range and can be supplied by a thermal storage system 208 as needed.

[0096] As already discussed, the thermal energy storage system 208 can be coupled to the power plant 212, which can use the thermal energy of the thermal energy storage system 208 to generate electricity. The power plant 212 can generate electricity on demand and load-follow the demand from the power grid. Often, the power plant 212 will generate waste heat, i.e., heat that is not used for power generation. This may be in the form of steam after passing through a steam turbine. This so-called waste heat may be recycled, for example, to supply district heating, which typically has lower temperature requirements than the applications of power plant 212 or industrial heat 512. Similarly, waste heat from industrial heat 512 applications can be captured and / or recycled to supply heat for other uses such as district heating, or it can be returned to the thermal energy storage system 208.

[0097] In one embodiment, the thermal storage system 208 can supply thermal energy to all required loads simultaneously. This can be achieved by scaling the thermal storage to a size that can supply the thermal power demand from all expected loads. The loads are variable, i.e., district heating 514 has a higher demand when the ambient temperature is colder, and power generation 212, such as for households, increases during the day and decreases at night. Therefore, the thermal storage system 208 can be set and configured to a size that supplies all the requirements of the required loads 510.

[0098] The thermal storage system 208 may include multiple storage facilities linked to one another. These storage facilities may contain the same or different thermal storage media and be maintained at different temperatures better suited to different heat loads. For example, some industrial heat applications 512 require temperatures above 800°C. In these cases, one or more individual storage facilities may store thermal energy above 800°C for supply to these high-temperature loads. Similarly, one or more individual storage facilities may supply relatively low-temperature thermal energy, such as 100°C to 300°C, to loads requiring lower temperatures. Of course, individual storage facilities may utilize different thermal storage media specifically designed to operate within the desired temperature range.

[0099] For example, a high-temperature storage facility may use a molten salt as a heat storage medium, which may be formulated to be thermally stable up to 1000°C or higher. A low-temperature storage facility has a high heat capacity (approximately 4.2 J / cm²). 3 Water can be used as a heat storage medium for (K).

[0100] Figure 6 illustrates various industrial heat applications in which a thermal storage system can supply the required thermal energy. As shown in the figure, district heating requires a temperature of approximately 50°C. This can be supplied by a thermal storage system that compensates for the efficiency of heat transfer by having a thermal storage medium that is stable at approximately 50°C, the thermal storage medium can be maintained at a temperature higher than the required temperature, and the heat exchanger can be in thermal communication with the district heating working fluid, which can be air, water, oil, or any other suitable working fluid, for a predetermined time sufficient to heat the working fluid to the desired temperature sufficient for district heating.

[0101] Most nuclear reactors operating today operate at temperatures in the lower half of the diagram, or below approximately 300°C. These reactors are thought to be able to store thermal energy at temperatures up to approximately 300°C, making them suitable for many lower-temperature thermal load applications, including power generation.

[0102] However, for higher temperature thermal applications (e.g., above 300°C), traditional water-cooled nuclear power plants cannot generate temperatures in this range. However, there are reactors designed to operate at around 500°C–550°C, which is suitable for supplying thermal energy up to their operating temperature. Other reactors are designed to operate at 750°C–800°C, providing heat in this range suitable for higher-temperature industrial applications. Even further reactors can operate at temperatures above 1000°C, suitable for supplying extremely high heat for industrial purposes. Fusion reactors, which are promised to operate at hundreds of millions of degrees Celsius, can supply even higher thermal energy than fission reactors.

[0103] Referring to Figure 7, an integrated energy system 700 is shown, in which a thermal energy storage system 702 is supplied with thermal energy from various heat sources. The thermal energy storage system 702 can be substantially the same as those described herein. One or more reactors 704, 706, 708 can be thermally connected to the thermal energy storage system 702. For example, when constructing the integrated energy system 700, a single, first reactor 704 may be constructed using existing reactor technology at the time, as shown in the figure. The thermal energy storage system 702 can be coupled to an energy conversion system 710 that converts thermal energy into electricity and supplies the electricity to an external load, etc.

[0104] In some cases, a second reactor 706, a third reactor 708, or more reactors can be coupled to a common thermal energy storage system 702. In some embodiments, one or more thermal energy sources, which may be a number of reactors, a wind energy system 712, a solar energy system 714, a geothermal energy system, or any combination of thermal energy sources, can be combined and coupled to the thermal energy storage system 7002 as part of an integrated energy system 700. The thermal energy sources supply thermal energy to the thermal energy storage system 702 via any suitable technology and components, which may differ for different thermal energy sources. In some cases, the thermal energy storage system 702 utilizes a working fluid for storing thermal energy, which may be the same working fluid used as a heat transfer fluid to supply thermal energy from the thermal energy sources to the thermal energy storage system 702.

[0105] As base load electricity demand increases over time, the thermal energy storage system 702 can be scaled up to increase its thermal energy storage capacity. Similarly, reactors can also be scaled, upgraded to utilize various technologies, or become additional reactors added as heat sources and coupled to the common thermal energy storage system 702. As an example, a sodium fast reactor can be constructed and coupled to the thermal energy storage system 702. As demand from external loads 716 increases, or as reactor technology advances to its technological readiness level, another reactor can be constructed and coupled to the thermal energy storage system 702. As an example, a molten salt reactor, a small modular reactor, a sodium pool reactor, or any other type of reactor can be constructed and coupled to the thermal energy storage system 702 in addition to, or instead of, the existing reactors coupled to the thermal energy storage system 702.

[0106] In many cases, multiple reactors can be constructed, each having its own reactor vessel, head, and site boundary, and everything beyond the site boundary can be common to multiple reactors. Of course, the reactors can be coupled to the thermal energy storage system 702 using pipes and valves. The energy supply system can use common or different heat transfer media to couple the reactors to the thermal energy storage system 702. By utilizing common components of the rest of the plant, such as a common thermal energy storage system 702, a common steam plant, a common heat transport, and a common energy conversion system 710, it is more efficient to scale the size of the thermal energy storage system 702 compared to constructing separate nuclear power plants for supplying electricity, each with its own specific requirements for the rest of the plant.

[0107] Having multiple reactors coupled to a common thermal energy storage system 702 offers the additional benefit of easier reactor maintenance. One reactor can be taken offline for maintenance or refueling without shutting down the entire system. In some cases, one or more thermal energy generation systems (e.g., reactors, wind energy system 712, solar thermal energy system 714, geothermal system, etc.) can be disconnected from the thermal energy storage system 702 and the energy conversion system 710, and as a result, one or more thermal energy systems can be taken offline without affecting the rest of the equipment or interrupting the supply of energy to the external load 716.

[0108] In one example, the heat transfer fluid is molten salt throughout the entire energy system, perhaps except for the reactor core, and this can be any of a number of coolants. For example, the energy transfer system 214 that carries thermal energy from the nuclear thermal plant 704 to the thermal energy storage system 702 can utilize molten salt as its working fluid. Similarly, the heat storage medium in the thermal energy storage system 702 may also be the same salt or molten salt as the working fluid of the energy transfer system 214. Furthermore, the energy supply system 216 that transfers heat from the thermal energy storage system 702 to the energy conversion system 710 may also be molten salt. Of course, the molten salt used throughout the entire system may be the same salt, or it may have different formulations specific to their intended use.

[0109] For example, when the thermal energy storage system 702 supplies heat to a district heating load, relatively low temperatures are required, and a salt (or other working fluid) specially formulated to perform well at the required lower temperatures may be used as the working fluid for supplying heat used for district heating.

[0110] In addition, other forms of thermal energy may be coupled to a heat storage system such as solar thermal energy 714 or wind energy 712. Often, the thermal energy storage system 702 is tolerant of thermal energy sources and can be coupled to a number of different types of thermal energy generators, such as a number of nuclear thermal plants, solar plants, wind plants, geothermal plants, hydroelectric plants, or other types of heat generation plants.

[0111] Figure 8 shows an exemplary energy system 800 in which multiple thermal energy sources are thermally coupled to a thermal energy storage system 702. The thermal energy sources can be any one or more of the multiple thermal energy systems, such as a reactor thermal plant 704, a solar thermal plant 714, a wind energy plant 712, or other types of thermal energy generation plants, or any combination of thermal energy generation plants.

[0112] The thermal energy plant supplies thermal energy to the thermal energy storage system 702, which stores thermal energy, by any suitable means such as a eutectic solution, a phase change material, a miscible gap alloy, a mixture of metals, a cement-based material, a molten salt (e.g., chloride salts, sodium nitrate, potassium nitrate, calcium nitrate, NaKMg, or NaKMg-Cl), solid or molten silicon, or a combination thereof or other materials. In some embodiments, the thermal energy storage system 702 utilizes the same working fluid as the thermal energy transfer fluid that receives thermal energy from one or more of the thermal energy generation plants. In some cases, the thermal energy transfer fluid is the same as the heat storage medium and is in fluid communication with it. In this example, the intermediate heat transfer loop may be omitted in some cases, and the heat storage medium can receive thermal energy directly from the thermal energy generation plants through a single heat transfer loop. The thermal energy plants can be in thermal communication with the thermal energy storage system 702 via one or more heat exchangers, but in some embodiments, a separate heat exchanger is used for each thermal energy plant to couple the thermal energy plants to the thermal energy storage system 702. In some cases, this allows for the addition or removal of multiple thermal energy sources from the system 800 as needed.

[0113] In one embodiment, the auxiliary power system 802 can be coupled to the thermal energy storage system 702. The thermal energy storage system 702 can selectively supply thermal energy to the auxiliary power system 802, which uses that thermal energy to generate power, such as to supply electricity to one or more reactors 704, 706, 708. In some cases, the auxiliary power system 802 can provide blackstart capability to one or more reactors. This can provide dedicated power to a reactor when starting it up in the event of a blackout or when electricity from the power grid is unavailable. This further isolates the reactor from the rest of the plant and from the power grid. Of course, the auxiliary power system 802 can supply backup power to any of the thermal energy generation plants, the thermal energy storage system 702, or any other system that benefits from uninterruptible backup power.

[0114] The thermal energy storage system 702 can be thermally coupled to an energy conversion system 710 that can generate energy for an external load, as described above. Often, the external load 716 requires either thermal energy or electricity, either of which can be supplied by the energy conversion system 710. In some cases, the energy conversion system 710 will convert thermal energy into electricity via a steam generator and turbine. However, in some cases, the thermal energy storage system 702 can directly supply compressed and heated gas to the turbine, eliminating the need for a steam generator, which is typically used in turbine power plants.

[0115] As an example, the thermal energy storage system 702 or energy conversion system 710 can use a heat storage medium to heat a working gas, such as nitrogen, argon, or hydrogen. The working gas may be heated and compressed to up to 4 atm, 5 atm, or 6 atm, but in some embodiments it is pressurized to less than 4 atm. The working gas can be heated to 600°C, 650°C, 700°C, 725°C, or 750°C or higher. The working gas can be supplied directly to a turbine, where it can then expand and drive the turbine. In some embodiments, the turbine operates in a Brayton cycle or a regenerative Brayton cycle. The gas pressure ratio can be selected and controlled to improve the efficiency of the Brayton cycle. Of course, other working gases can be used, such as immiscible salts, which vaporize at the operating temperature and can be used to drive the turbine.

[0116] Figure 9 shows an embodiment of the integrated energy system 900, in which a nuclear heat plant 200 supplies thermal energy to the thermal storage system. Although a single nuclear heat plant 200 is illustrated, it should be understood that two or more nuclear heat plants and / or other thermal energy plants can be combined to supply thermal energy to the thermal energy storage system 702. The thermal energy storage system 702 then supplies thermal energy to one or more loads 510, which may include loads of power generation 212, district heating 514, or industrial heat 512. In some cases, the loads 510 may be relatively low for several days or weeks, and the thermal energy storage system 702 may become thermally saturated. That is, the thermal energy storage system 702 may not be able to receive any additional heat from the nuclear heat plant or other connected thermal energy sources. Thus, the thermal energy generated by the thermal energy generation plants can be transferred to several other beneficial auxiliary heat uses 902. In some cases, excess heat is released into the atmosphere, but in other cases, excess heat exceeding what the heat storage system can receive can be used for other processes, particularly, for example, water desalination or hydrogen production. Of course, the auxiliary heat utilization 902 can also be supplied with thermal energy even when the heat storage system is not saturated. For example, thermal energy from a thermal energy source may be supplied to the thermal energy storage system 702 and at the same time used for the auxiliary heat utilization 902.

[0117] These auxiliary heat utilization systems 902 can receive a portion of the thermal energy before it is supplied to the thermal energy storage system 702, or they can selectively receive all of the generated thermal energy, for example, when the heat storage system is full, or when auxiliary heat utilization 902 is considered a higher and better purpose for the thermal energy than storing the thermal energy for later use.

[0118] In one embodiment, the thermal energy storage system 702 is located at a height above the power generation system 212. For example, the thermal energy storage system 702 may be constructed on a hill so as to be at a height higher than the power plant 212. This arrangement utilizes a combined energy storage mode by combining both thermal energy and the pressure due to gravity on the downstream system due to the height change. The combined energy storage mode increases the overall energy density. For example, a typical steam turbine system requires one or more pumps to pump the working fluid through the turbine system. The pumps are generally sized to correspond to the peak load and are selected to meet the peak load demand by pumping the working fluid through the turbine system in a higher volume per unit time. By relying on gravity, the system can deliver additional heat through the steam generator and then to a cold storage tank. In one embodiment, this arrangement can reduce the size required for one or more pumps or eliminate one or more pumps in the steam turbine system.

[0119] In one embodiment, existing containment sites may be suitable for constructing nuclear thermal plants to be coupled with thermal storage systems. Currently, there are numerous reactor sites that are no longer in operation or are scheduled to be decommissioned and cease operations. These sites can be referred to as brownfield sites (vacant lots for redevelopment, existing industrial sites), a nomenclature defined by the Environmental Protection Agency as real estate where the presence or potential presence of hazardous materials, contaminants, or contaminants could complicate expansion, reuse, or development. Decommissioned reactor sites are a type of physical site that falls within the definition of brownfield sites.

[0120] However, reactor brownfield sites offer several advantages to the systems and methods disclosed or described herein. For example, reactor brownfield sites have existing civil work structures such as roads, utilities (e.g., power lines, sewers, water lines, etc.), site boundary security, containment buildings, pipes, valves, and outbuildings. Many of these structures can be reused in nuclear thermal plants, which can significantly reduce the time and cost required for the construction and commissioning of nuclear thermal plants.

[0121] Many reactor brownfield sites have containment structures designed to house high-pressure reactors such as light water reactors ("LWRs"). These containment structures are designed far beyond the containment structures that newer generations of nuclear thermal plants will require, many of which operate at relatively lower pressures compared to LWRs. The thermal energy storage system 702 can be located away from the reactor brownfield site and can be thermally coupled to the nuclear thermal plant, as described herein, for example, via a heat transfer fluid loop. Passages can be created within the containment structure to allow the heat transfer medium to exit the containment structure and transfer thermal energy to the thermal energy storage system 702 located away from the reactor site.

[0122] Existing containment structures can be configured to accommodate one, two, or more nuclear thermal plants. For example, a single containment structure can house multiple reactors sharing the containment structure, fuel handling systems, and other components. A containment structure may be divided into two or more reactor chambers to accommodate multiple reactors and their associated support structures. Two or more reactors may share, among other things, fuel storage areas, subsystems, reactor core fuel supply / removal systems, and fuel polishing systems.

[0123] In some cases, it is desirable to operate the reactor at full power. The systems and methods described herein allow the reactor to remain at continuous full power by separating it from the thermal storage and power generation systems. The reactor can continuously supply thermal energy to the thermal storage system, which can be made large enough to store and supply more energy than the reactor can supply. Thus, the reactor can slowly "charge" the thermal storage system over time. If the reactor generates excess heat that the thermal storage system cannot receive, the excess heat may be transferred and used for auxiliary purposes such as industrial process heat, desalination, hydrogen production, or any other beneficial purpose. Of course, the excess heat may be released into the atmosphere alternatively or additionally.

[0124] Figure 10 shows an exemplary embodiment of an integrated energy system having a nuclear thermal plant 200 coupled to a thermal energy storage system 702. Additional hybrid energy sources 1002, such as wind power, solar power, geothermal power, wave power, or other renewable energy sources, can similarly be coupled to the thermal energy storage system 702. As shown, the nuclear thermal plant 200 is located within the reactor site boundary 210 and EPZ, while the remaining systems, such as the thermal energy storage system 702 and the power conversion system 212, are located outside the reactor site boundary 210 and EPZ.

[0125] The traditional use of nuclear power plants is power generation. However, many newer fourth-generation nuclear power plants are designed to have outlet temperatures exceeding 500°C, significantly higher than those of light water reactors (LWRs). Thus, the potential applicability of this high-grade heat extends far beyond power generation. In the illustrated structure, reactor 200 is used as a heat source to be delivered to a separate thermal energy storage system 702 located outside the reactor site boundary 210. In addition to being carbon-free, or at least having low carbon emissions, combined with the diffusion prevention properties of newer reactors, the structure of this integrated energy system 1000 enables many beneficial features, including (1) reduced reactor and total system costs, (2) flexible power demand (load) following and "profit following" in the power grid with greater penetration of renewable energy, (3) supplying high-temperature process heat at a cost competitive with natural gas, which is not currently possible with LWRs, and (4) enabling hydrogen production by high-temperature electrolysis.

[0126] These capabilities will enable dramatic carbon reductions in the industrial processes and transportation sectors, which currently account for approximately 75% of global greenhouse gas emissions.

[0127] One of the current obstacles facing nuclear power plants is the upfront investment in construction and licensing costs associated with their construction and commissioning. One of the major cost factors in nuclear power plant construction is not the nuclear technology itself, but rather the cost of the large-scale construction project regulated by stringent nuclear standards. Therefore, one of the greatest promises of capital cost reduction is not necessarily technological advancements in the reactor itself, but rather the plant design. As described herein, by greatly simplifying and reducing the scope and complexity of the construction project within the reactor site, the major cost factors associated with constructing a typical nuclear power plant are dramatically reduced. In the various structural embodiments described herein, the scope of the nuclear power plant and reactor construction project is reduced to its most basic form. The simplified reactor becomes a producer of thermal energy, and is referred to here as a nuclear thermal plant.

[0128] In one embodiment, the interface between the nuclear thermal plant and the rest of the integrated energy system is a heat exchanger, and the remaining system components downstream of the heat exchanger are functionally and spatially isolated from the nuclear thermal plant. In this structure, the thermal energy storage and the rest of the plant, including the power conversion system, are constructed and operated in a less regulated, less expensive, and fully commercialized environment.

[0129] Molten salt thermal storage systems are relatively inexpensive, often an order of magnitude cheaper than battery storage, and have achieved commercial readiness on a GWh scale. Suitable thermal storage systems are currently being used to support the concentrated solar power industry. Furthermore, due to the superior safety advantages of the advanced reactors described herein, very small EPZs are possible, which allows these reactors to be placed closer to the heat consumers.

[0130] The described integrated energy systems also address other challenges that nuclear power faces in current and future electricity markets. For example, as the proportion of electricity generated by intermittent renewable energy sources increases, there are large fluctuations in electricity supply, typically during the 9 a.m.-4 p.m. time, accompanied by overproduction, and solar energy pushes electricity prices down to very low levels, or even into negative territory. Current nuclear power plants typically have limited flexibility in rapid load following and are sometimes driven to maintain relatively high capacity utilization rates to achieve low levels of cost of electricity (LCOE). Thus, even if nuclear power plants could adapt to the daily fluctuating electricity demand, their LCOE would increase, making it difficult to compete with alternative technologies. Salt thermal storage would allow many types of nuclear thermal plants to operate at 100% capacity utilization (or very close to it), storing energy in thermal energy storage tanks, such as salt tanks, and selling the electricity during periods of high demand and high prices.

[0131] A key consideration in reducing greenhouse gas emissions is the extension of decarbonization to other industrial processes. Energy consumption in this sector is enormous, primarily in the form of heat, with petroleum and chemicals being the main consumers. The integrated energy systems described herein, having high outlet temperatures of approximately 510°C to 540°C or higher and heat storage media suitable for these temperatures, offer the opportunity to supply heat to numerous consumers up to approximately 500°C, such as oil refineries, various chemical plants, soda ash production plants, pulp and paper plants, and food processing plants. There is also significant potential for cogeneration power plants that produce both heat and electricity.

[0132] The transportation sector accounts for the second largest share of global energy consumption, after industrial manufacturing. Until recently, transportation relied solely on gasoline fuel, and clean nuclear energy was not involved in this sector. This is changing with the recent arrival of hydrogen-powered, battery- and fuel cell-powered electric vehicles. Integrated energy systems, such as those described herein, can provide both of these products without carbon emissions, significantly impacting the decarbonization of the transportation sector.

[0133] The integrated energy system described herein can produce hydrogen using high-temperature electrolysis and heat. The stored thermal energy can be used to generate steam from water, and hybrid energy such as electricity can be used to raise the temperature in the electrolysis apparatus to 750°C to 900°C, such as through ohmic heating. In one embodiment, a heat exchanger in the electrolysis apparatus can recover heat from the hydrogen and oxygen flows to reduce the amount of ohmic heating energy required to maintain the electrolysis apparatus temperature at a desired temperature or, in some cases, above a threshold temperature. Furthermore, the described integrated energy system can simultaneously generate both electricity, such as charging a car battery, and hydrogen. For example, when electricity is not needed, the generated thermal energy can be used to produce additional hydrogen, which can then be stored for long-distance distribution, similar to what is currently done with gasoline. Unlike GW-scale heat storage, which is limited to periods of a few hours or relatively short transport distances, hydrogen can be stored for much longer periods and is transportable over long distances. Thus, hydrogen can be generated using the integrated energy system, which can be stored for long periods, transported over long distances, and later used as a fuel source.

[0134] In some embodiments, a nuclear thermal plant and an integrated energy system can be coupled, either exclusively or partially, to a hydrogen production plant, which can utilize an electrolytic process that uses electricity to separate water into hydrogen and oxygen. In some examples, the integrated energy system can supply thermal power to the generated steam for use in hydrogen steam reforming in a natural gas process. In some cases, a high-temperature electrolysis process is a process in which a large amount of electrolytic energy can be supplied by heat, thereby reducing the amount of electrical energy and thus reducing the cost of producing hydrogen. In some cases, a high-temperature electrolysis process utilizes thermal energy having a temperature of about 800°C, which can be supplied by an integrated energy system such as those described herein.

[0135] Figure 11 shows an integrated energy system 1100 having a nuclear block 1102 in communication with an integrated energy storage block 1104. The integrated energy storage block 1104 then communicates with a power block 1106. The power block 1106 can communicate with an external load 1108. According to one embodiment, the nuclear block 1102 comprises one or more reactors, such as nuclear thermal plants, having a reactor site boundary 1110 surrounding a nuclear island, as described herein. One or more nuclear thermal plants may be included as part of the nuclear block 1102, or one or more nuclear thermal plants may be coupled to the integrated energy storage block 1104 and maintain their own separate reactor site boundary 1110. The integrated energy storage block 1104 may consist of any suitable heat storage as described herein, and may include, for example, a salt tank that relies on a phase-change material to store thermal energy at a stable temperature in order to receive thermal energy from the nuclear block. The integrated energy storage block 1104, also referred to herein as a thermal storage system or thermal energy storage system, is separated from the nuclear block 1102 by a boundary 1112, which may be defined by the reactor site boundary 1110. In some examples, the primary communication (transfer) between the nuclear block 1102 and the integrated energy storage block 1104 is one or more heat exchangers that transmit the thermal energy generated by the nuclear block 1102 to the integrated energy storage block 1104.

[0136] The integrated energy storage block 1104 is in thermal communication with the power block 1106. Thermal communication may be achieved by one or more heat exchangers configured to transmit thermal energy from the integrated energy storage block 1104 to the power block 1106. The power block 1106 may, for example, convert the thermal energy into electricity, which may be done by a turbine such as a steam turbine, or some other type of thermal-to-electrical energy conversion system. The power block 1106 can utilize the thermal energy to generate electricity and transmit it to an external load 1108, for example, a power grid.

[0137] As the world moves away from coal-fired power plants for a variety of reasons, the equipment of decommissioned coal-fired power plants can be utilized by other energy sources. For example, when a coal-fired power plant is decommissioned, the equipment downstream of the boiler is tolerant of heat sources. For instance, the turbine block, switchyard, capacitors, generators, and electrical wiring can all still be used by another heat energy source. These valuable assets, which become orphan assets when a coal-fired power plant is decommissioned, create an opportunity for another, carbon-free heat energy source to utilize the orphan assets and continue generating electricity.

[0138] According to some embodiments, the coal-fired, remaining power blocks of the plant (e.g., all downstream of the boiler), along with associated piping, instrumentation and control, include equipment such as boiler drums, pendant superheaters, high-pressure turbines, reheaters, intermediate-pressure turbines, low-pressure turbines, condensers, feed pumps, deaerators, feed heaters, economizers, cooling towers, generators, transformers, and power transmission systems. These isolated assets are tolerant of thermal energy sources that may be supplied by integrated energy storage blocks 1104 (e.g., thermal storage systems) as described herein.

[0139] The integrated energy storage block 1104 can receive thermal energy from any of a number of thermal energy sources, such as one or more nuclear thermal plants, solar thermal energy, geothermal energy, wind thermal energy, wave energy, or any other suitable generator of thermal energy. According to one embodiment, the integrated energy storage block 1104 makes it possible to combine any form of thermal energy and make it available for use with any form of power block 1106, providing the further advantage of separating the nuclear block 1102 from the power block 1106.

[0140] This structure offers many advantages. For example, there is regulatory separation between the nuclear block 1102 and all downstream equipment of the integrated energy storage block 1104, and there is flexibility in adapting the nuclear block 1102 to the power block 1106. For instance, the nuclear block 1102 does not need to be adapted to the power block 1106 in terms of power output. The nuclear block 1102 operates at full power, transmitting thermal energy to the integrated energy storage block 1104, which can then supply thermal energy to drive the turbine of the power block 1106 in any suitable manner. Thus, the operation of the power block 1106 is completely independent of the operation of the nuclear block 1102.

[0141] According to one embodiment, the nuclear power block 1102 can be operated at 100% capacity, but since the nuclear power block 1102 is isolated from the power block 1106 by the integrated energy storage block 1104, the power block 1106 can fully load-follow the power demand.

[0142] The described structures also offer advantages in design efficiency. It is no longer necessary to adapt a reactor to a specific power block 1106. A general-purpose reactor can be adapted to a general-purpose power block, thereby eliminating the need to develop a new reactor to adapt power to each arbitrary power block. A general-purpose reactor refers to a reactor of any design and power output. A general-purpose power block refers to a thermal-to-electrical energy conversion system of any design, size, type, and power output, including, for example, a steam generator.

[0143] In one embodiment, the integrated energy storage block 1104 is designed to accept the output of the nuclear block 1102 and supply thermal energy according to the requirements of the power block 1106. In one embodiment, the described structure allows for the adaptation of a single reactor design or a combination of multiple reactor designs to the power block 1106. For example, if the power block requires 1600 MWth of steam for the turbine, that requirement can be met by one 1600 MWth reactor, two 800 MWth reactors, one 1200 MWth reactor and one 400 MWth reactor, and so on. In some examples, the integrated energy block 1104 acts as an aggregator from one or more reactor designs, and thus, by relying on the integrated energy block 1104 as a buffer, flexibility, scalability, and temporal independence of the coupling of the power block 1106 to one or more reactors is enabled. This further allows the nuclear block 1102 and the power block 1106 to be completely separate and independent from a design, construction, and operational standpoint. A further advantage is that this structure enables the use of a single reactor design, such as a 400 MWth plant, in conjunction with multiple types of power blocks (e.g., 400 MWth, 800 MWth, 1200 MWth, 1600 MWth, 2000 MWth, 2400 MWth, etc.). In some embodiments, a true mismatch may exist between the nuclear block 1102 and the power block 1106; for example, a reactor block 1102 outputting 1600 MWth may be compatible with a 1500 MWth power block 1106. In other words, the nuclear block 1102 may have a thermal power output, and the power block 1106 may have a thermal power input greater than or less than the thermal power output of the nuclear block 1102. In other words, reactor block 1102 may have a different nameplate capacity than power block 1106. As used herein, the nameplate capacity is the full load sustaining output of the facility.Nameplate capacity is typically a number registered with a regulatory body to classify the power output of a station, and is usually measured in watts, megawatts, or gigawatts. When used to describe power block 1106, nameplate capacity may be used to refer to the power input (power input) to power block 1106, which can be converted to power when power block 1106 is operating at full output.

[0144] This type of non-conformity can be addressed in the manner described herein, to name a few, by scaling the integrated energy storage block by using excess thermal energy for other purposes, by planning nuclear shutdowns while still supplying thermal energy from the integrated energy storage block to the power block, or by allowing the nuclear block 1102 to charge the integrated energy storage block 1104 during times of reduced power demand. In some cases, the power block 1106 can be operationally scaled back to a power output lower than 100% capacity, while the nuclear block 1102 can operate at 100% operational capacity.

[0145] Similarly, the reactor block 1102 can be coupled to an integrated energy storage block 1104 which has a mismatch between the thermal power generation capacity (capacity) of the nuclear block 1102 and the heat storage capacity (capacity) of the heat storage block 1104. In other words, the nuclear block 1102 may have a generation capacity (capacity) less than the storage capacity (capacity) of the heat storage block. In some cases, the generation capacity of the reactor block may be on the order of 10%, 20%, 30%, 40%, 50%, 60%, 70%, or 80% of the storage capacity of the heat storage block.

[0146] In some cases, the nuclear block 1102 generates thermal energy at a temperature that may not be ideal for the power block 1106. For example, the nuclear block 1102 may provide an outlet temperature of 500°C, while the power block 1106 may require steam at 550°C. In these cases, the temperature deficit can be compensated for by (1) a Peeker tank that can heat the heat storage medium to a higher temperature, (2) adding additional thermal energy to the steam before it is sent through the turbine, (3) operating the turbine at a lower efficiency, or by utilizing some other solution to address the temperature mismatch.

[0147] In one embodiment, hybrid technology can be used to supplement the thermal energy of the nuclear block 1102. For example, if the power block 1106 requires a higher inlet steam temperature than the nuclear block 1102 can supply, alternative technologies such as ohmic heating, natural gas, hydrogen, or some other energy source can be used to peak the steam temperature and operate the power block 1106 with appropriate efficiency.

[0148] In one embodiment, utilizing an isolated power block 1106 asset in conjunction with a nuclear thermal plant in an integrated energy system 1100 yields numerous benefits. For example, the site is already approved and operational, and the layout is already in place, which allows the hundreds of millions of dollars worth of equipment to be further utilized in carbon-free power generation operations rather than being scrapped, and the site is already connected to the transmission infrastructure and power grid, along with other benefits.

[0149] The above description of combining the nuclear power block 1102 and the integrated energy storage block 1104 with an isolated coal power block 1106 asset is equally applicable to isolated natural gas assets. As gas-fired power plants are decommissioned for a number of different reasons, the power blocks from these plants can be utilized by combining the power block 1106 with the integrated energy storage block 1104, which supplies thermal energy, to drive the turbines of the gas-fired power plants. The integrated energy storage block 1104 can receive thermal energy from any of a number of different sources, such as one or more nuclear reactors, solar thermal energy, wind energy, geothermal energy, hydroelectric energy, or any other suitable thermal energy source.

[0150] In some cases where the power block 1106 requires a temperature higher than the output temperature of the integrated energy storage block 1104, the decommissioned gas-fired power plant would have an available source of natural gas that can be used to raise the temperature of the heat storage medium or turbine working fluid to peak in order to improve the efficiency of the turbine cycle. In addition, although the power block 1106 itself may generate power at a lower efficiency because it is below the optimal inlet steam pressure, it can transfer some of the power it generates to peak the temperature of the inlet steam, and gradually increase its efficiency as the inlet steam rises to a more ideal temperature for the power block.

[0151] In one embodiment, a brownfield site offers an opportunity to utilize isolated equipment by combining it with an integrated energy storage block 1104 and a nuclear block 1102. By utilizing existing infrastructure (core facilities, social production infrastructure) available on a brownfield site, it becomes possible to refurbish and develop sites that would otherwise be difficult to use into carbon-free energy production facilities at a much lower cost than new construction, and with reduced licensing and commissioning time and costs, thereby redeveloping the site for active use.

[0152] Embodiments described herein provide an integrated energy system that separates a thermal energy source from an energy conversion system, providing a modular, scalable, and efficient system that can be used to meet not only industrial process heat but also base and peak electrical load demands. One or more thermal energy sources, such as one or more nuclear reactors of various types, solar power plants, geothermal energy sources, etc., can be coupled to the rest of the plant's systems, such as thermal storage and energy conversion systems.

[0153] Those skilled in the art will recognize that any process or method disclosed herein can be modified in many ways. The process parameters and sequences of the processes described and / or illustrated herein are given merely as examples and can be changed as desired. For example, the processes illustrated and / or described herein may be shown or described in a particular order, but these processes do not necessarily have to be performed in the order illustrated or described.

[0154] Various exemplary methods described and / or illustrated herein may omit one or more of the steps described or illustrated herein, or may include additional steps in addition to the disclosed steps. Furthermore, any step of any method disclosed herein may be combined with any one or more steps of any other method disclosed herein.

[0155] Unless otherwise specified, the terms “connected” and “joined” (and their derivatives) used in the specification and claims should be interpreted as allowing both direct and indirect (i.e., through other elements or components) connection. Furthermore, the terms “a” or “an” used in the specification and claims should be interpreted as meaning “at least one of.” Finally, for ease of use, the terms “include” and “have” (and their derivatives) used in the specification and claims should be interchangeable with the word “equipped” and have the same meaning.

[0156] As used herein, the term "or" is used inclusively to refer to items in terms of alternatives and combinations. As used herein, letters such as numbers refer to similar elements.

[0157] Embodiments of the present invention are shown and described herein and are provided merely as examples. Those skilled in the art will recognize numerous adaptations, modifications, variations, and substitutions without departing from the scope of this disclosure. Several substitutes and combinations of the embodiments disclosed herein may be used without departing from the scope of this disclosure and the invention disclosed herein. Accordingly, the scope of the invention of this disclosure shall be defined solely by the appended claims and their equivalents. This disclosure also includes the following numbered clauses.

[0158] 1. It is a system, The reactor located on the reactor site, A reactor site boundary surrounding the reactor, defined by one or more barriers that restrict access to the reactor site, A thermal energy storage system located outside the reactor site boundary, comprising a thermal energy storage system that is in thermal communication with the reactor, A generator that is in thermal communication with the thermal energy storage system, the generator located outside the reactor site boundary, A system characterized by including

[0159] 2. Furthermore, the system according to Clause 1, characterized in that it includes a containment building, and the reactor is enclosed within the containment building.

[0160] 3. Furthermore, the system according to Clause 1, characterized in that it includes a fuel handling area, the fuel handling area being located within the reactor site boundary.

[0161] 4. The system according to Clause 1, characterized in that the thermal energy storage system is in thermal communication with the reactor by an energy transfer system.

[0162] 5. The system according to Clause 4, wherein the energy transfer system includes a fluid loop, and the fluid loop forms a closed loop between the reactor and the thermal energy storage system.

[0163] 6. The system according to Clause 5, characterized in that the fluid loop of the energy transfer system is in thermal communication with the reactor by a first heat exchanger and in thermal communication with the thermal energy storage system by a second heat exchanger.

[0164] 7. The system according to Clause 5, characterized in that the fluid loop includes a working fluid.

[0165] 8. The system according to Clause 7, characterized in that the working fluid contains a chloride salt.

[0166] 9. The system according to Clause 7, characterized in that the working fluid contains sodium nitrate.

[0167] 10. The system according to Clause 7, characterized in that the working fluid contains a eutectic solution.

[0168] 11. The system according to Clause 7, characterized in that the working fluid includes a phase change material.

[0169] 12. The system according to Clause 7, characterized in that the working fluid includes a miscible gap alloy.

[0170] 13. The system according to Clause 7, characterized in that the working fluid contains molten metal or a metal alloy.

[0171] 14. The system according to Clause 6, characterized in that the first heat exchanger or the second heat exchanger is a cylindrical multi-tube heat exchanger.

[0172] 15. The system according to Clause 6, characterized in that the first heat exchanger or the second heat exchanger is a double-pipe heat exchanger.

[0173] 16. The system according to Clause 6, characterized in that the first heat exchanger or the second heat exchanger is a plate heat exchanger.

[0174] 17. Furthermore, the system according to Clause 1 is characterized by including a hydrogen generator coupled to the thermal energy storage system.

[0175] 18. The system according to Clause 1, characterized in that the reactor site boundary includes a fence.

[0176] 19. The system according to Clause 1, characterized in that the reactor is a fast neutron reactor.

[0177] 20. The system according to Clause 1, characterized in that the reactor is a breeder reactor.

[0178] twenty one. The system according to Clause 1, characterized in that the reactor is a thermal neutron reactor.

[0179] twenty two. The system according to Clause 1, characterized in that the reactor is a heavy water reactor.

[0180] twenty three. The system according to Clause 1, characterized in that the reactor is a light water reactor.

[0181] twenty four. The system according to Clause 1, characterized in that the reactor is a molten salt reactor.

[0182] twenty five. The system according to Clause 1, characterized in that the reactor is a liquid metal-cooled reactor.

[0183] 26. The system according to Clause 1, characterized in that the reactor is a gas-cooled reactor.

[0184] 27. The system according to Clause 1, characterized in that the thermal energy storage system is coupled to an energy conversion system having a thermal power input greater than the thermal power output of the reactor.

[0185] 28. The system according to Clause 1, characterized in that the thermal energy storage system is a low-pressure system.

[0186] 29. The system according to Clause 28, characterized in that the energy transport system is configured to transfer thermal energy from the reactor to the thermal energy storage system.

[0187] 30. The system according to Clause 29, characterized in that the energy transport system is a low-pressure system.

[0188] 31. The system according to Clause 1, characterized in that the generator is in thermal contact with the thermal energy storage system by an energy supply system.

[0189] 32. The energy supply system according to clause 31, characterized in that it includes a closed fluid loop.

[0190] 33. The system according to clause 32, characterized in that the closed fluid loop contains a molten salt.

[0191] 34. The system according to Clause 31, characterized in that the energy supply system includes a working fluid that is in direct contact with the heat storage medium in the thermal energy storage system.

[0192] 35. The system according to Clause 1, characterized in that the generator is a steam turbine.

[0193] 36. The system according to Clause 35, characterized in that the steam turbine converts steam into mechanical work.

[0194] 37. Furthermore, it includes a generator coupled to the steam turbine by the output shaft of the steam turbine, The system according to Clause 36, characterized in that the mechanical operation causes the generator to generate electricity.

[0195] 38. The system according to Clause 37, characterized in that the generator is configured as a load-following power generation system.

[0196] 39. The system according to Clause 1, characterized in that the reactor is a first reactor, and the system further includes a second reactor.

[0197] 40. The second reactor is located on the second reactor site within the boundary of the second reactor site, The system according to Clause 39, characterized in that the thermal energy storage system and the generator are located outside the second reactor site boundary.

[0198] 41. Furthermore, the system according to Clause 1 is characterized by including an auxiliary heat storage system that is in thermal communication with the reactor.

[0199] 42. The system according to Clause 41, characterized in that the auxiliary heat storage system is configured to adjust the inlet temperature of the reactor core.

[0200] 43. Furthermore, the system according to Clause 1 is characterized by including a solar thermal energy system that is in thermal communication with the thermal energy storage system.

[0201] 44. The system according to Clause 1, further characterized in that it includes an emergency planning area around the reactor, and the thermal energy storage system and the generator are located outside the emergency planning area.

[0202] 45. The system according to any of the preceding clauses, wherein the reactor comprises a reactor vessel, a primary coolant loop at least partially located within the reactor vessel, and a primary heat exchanger in thermal communication with the primary coolant loop.

[0203] 46. The system according to Clause 45, characterized in that the primary heat exchanger is a sodium-salt heat exchanger.

[0204] 47. The system according to Clause 45, characterized in that the primary heat exchanger transfers thermal energy from the reactor core to the working fluid of the thermal energy storage system.

[0205] 48. It is a system, A reactor located within the site boundary of a nuclear reactor, having a reactor vessel, A heat exchanger within the reactor vessel, configured to thermally couple the primary coolant within the reactor vessel with the salt coolant in the coolant loop, A thermal energy storage system located outside the reactor site boundary and configured to receive thermal energy from the salt coolant of the coolant loop, A system characterized by including

[0206] 49. The system according to Clause 48, further comprising a power generation system that is in thermal communication with the thermal energy storage system, wherein the power generation system is located outside the reactor site boundary.

[0207] 50. The system according to Clause 49, characterized in that the reactor has a first nameplate capacity, the power generation system has a second nameplate capacity, and the second nameplate capacity is greater than the first nameplate capacity.

[0208] 51. It is a system, A nuclear reactor having thermal power output, A power generation system having a thermal power input that is in thermal communication with the aforementioned nuclear reactor, Includes, A system characterized in that the thermal power input is greater than the thermal power output.

[0209] 52. The system according to Clause 51, further comprising a heat storage system disposed between the reactor and the power generation system, wherein the heat storage system receives thermal power from the reactor and supplies thermal power to the power generation system.

[0210] 53. The system according to Clause 52, characterized in that the heat storage system is sized to supply a greater amount of thermal power than that the reactor can supply.

[0211] 54. Furthermore, including the reactor site boundary, The system according to Clause 51, characterized in that the reactor is located within the reactor site boundary.

[0212] 55. The power generation system is characterized by being located outside the reactor site boundary, as described in Clause 54.

[0213] 56. The system according to any of the preceding clauses, comprising a primary heat exchanger, wherein the primary heat exchanger is a sodium-salt heat exchanger.

[0214] 57. The system according to Clause 56, characterized in that the primary heat exchanger is located within the reactor vessel of the reactor.

[0215] 58. The system according to Clause 57, characterized in that the first heat exchanger is in thermal communication with the heat storage system.

[0216] 59. The system according to Clause 52, further characterized by including a second reactor that is in thermal communication with the heat storage system.

[0217] 60. The system according to Clause 59, characterized in that the second reactor is a reactor of a different design from the first reactor.

[0218] 61. Furthermore, the system according to Clause 52 is characterized by including a solar thermal plant that is in thermal communication with the heat storage system.

[0219] 62. Furthermore, the system according to Clause 52, characterized in that it includes a wind heat plant that is in thermal communication with the heat storage system.

[0220] 63. The system according to any of the preceding clauses, characterized in that the reactor is isolated from the heat storage system and the power generation system.

[0221] 64. Furthermore, the system according to any of the preceding clauses is characterized by including a hydrogen generator that receives thermal energy and produces hydrogen.

[0222] 65. The system according to Clause 64, characterized in that the hydrogen generator includes an electrolysis device.

[0223] 66. The system according to Clause 65, wherein the hydrogen generator produces hydrogen via a high-temperature electrolysis process.

[0224] 67. The system according to Clause 64, wherein the hydrogen generator produces hydrogen via a steam reforming process using natural gas. [Brief explanation of the drawing]

[0225] [Figure 1] This shows a typical nuclear power plant. [Figure 2] This shows a nuclear thermal plant separated from a power plant, according to one embodiment. [Figure 3] This shows a nuclear thermal plant combined with a thermal energy storage plant, according to one embodiment. [Figure 4]This shows a nuclear thermal plant coupled with a remote thermal storage plant having an optional auxiliary thermal storage plant, according to one embodiment. [Figure 5] This shows a nuclear thermal plant coupled to a remote thermal storage system coupled to an external load, according to one embodiment. [Figure 6] This shows exemplary industrial heating applications and required temperatures. [Figure 7] This invention illustrates an energy system in which multiple heat sources share a common heat storage and energy conversion system, according to one embodiment. [Figure 8] This invention illustrates an energy system in which multiple heat sources share a common heat storage and energy conversion system with an auxiliary power system, according to one embodiment. [Figure 9] This document shows a nuclear thermal plant coupled to a remote heat storage system connected to an external load and auxiliary heat utilization, according to one embodiment. [Figure 10] This invention illustrates a hybrid energy system in which multiple forms of thermal energy generators are coupled to a common thermal storage system and a common power conversion system, according to one embodiment. [Figure 11] This describes an energy system in which the nuclear power block is separated from the power block by an integrated energy storage block, according to one embodiment.

Claims

1. To generate thermal energy, the process involves operating the reactor at full capacity, The steps include transferring the thermal energy from the reactor to the heat storage system in order to charge the heat storage system at a constant rate, The steps include providing thermal energy from the heat storage system to the power generation system, A method comprising the steps of generating electricity from the power grid, at least partially based on the electricity load demand, using the power generation system to track the electricity load demand from the power grid.

2. The method according to claim 1, wherein the heat storage system is located outside the nuclear site boundary surrounding the reactor, and the nuclear site boundary is defined by a plurality of barriers that restrict access to the reactor site.

3. The method according to claim 2, wherein the emergency planning area surrounds the reactor, and the heat storage system and the power generation system are located outside the emergency planning area.

4. The method according to claim 1, wherein the step of transferring the thermal energy includes transferring the thermal energy by an energy transfer system that includes a fluid loop forming a closed loop between the reactor and the heat storage system.

5. The method according to claim 4, wherein the fluid loop contains a molten salt as a working fluid.

6. The method according to claim 5, wherein the molten salt comprises a chloride salt and / or a nitrate salt.

7. The method according to claim 4, wherein the fluid loop is in thermal communication with the reactor by a first heat exchanger and in thermal communication with the heat storage system by a second heat exchanger.

8. The method according to claim 1, wherein the step of operating the reactor includes the step of circulating a primary coolant in a primary coolant loop located within the reactor vessel of the reactor.

9. The method according to claim 8, wherein the step of transferring thermal energy includes transferring thermal energy from the primary coolant loop by a primary heat exchanger which is a sodium-salt heat exchanger.

10. The heat storage system includes a high-temperature tank and a low-temperature tank. The method according to claim 1, wherein the step of transferring thermal energy includes circulating a heat storage medium between the high-temperature tank and the low-temperature tank.

11. The heat storage system according to claim 1, wherein the heat storage system has a plurality of heat storage bodies and stores thermal energy at different temperatures.

12. The method according to claim 1, wherein the step of providing thermal energy from the heat storage system to the power generation system includes the steps of transferring the thermal energy to a steam generator to generate steam, and supplying the steam to a steam turbine mechanically coupled to the generator.

13. The method according to claim 1, wherein the step of generating power that follows the electrical load demand includes the step of changing the heat output supplied from the heat storage system to the power generation system while continuing to operate the reactor at full capacity.

14. The method according to claim 1, further comprising the step of providing thermal energy from the thermal storage system to an industrial heating load and / or a district heating load.

15. The method according to claim 1, further comprising the step of transferring thermal energy to an auxiliary heat utilization, including water desalination and / or hydrogen production, when the heat storage system reaches a state of thermal saturation.

16. The method according to claim 1, wherein the heat storage system has a thermal energy capacity greater than the thermal power output of the reactor.

17. The method according to claim 1, wherein the power generation system has a thermal power input greater than the thermal power output of the reactor.

18. The method according to claim 1, wherein the electrical load demand is lower than the thermal power output of the reactor, the thermal storage system is charged by the step of transferring the thermal energy, and the thermal storage system is discharged by the step of supplying the thermal energy from the thermal storage system to the power generation system.

19. The method according to claim 1, wherein the electrical load demand is higher than the thermal power output of the reactor, and the heat storage system discharges at a rate exceeding the rate at which it is charged.

20. The method according to claim 1, comprising the steps of connecting a second reactor to the heat storage system and transferring thermal energy from the second reactor to the heat storage system.

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