Off-peak energy storage

Abstract

The present disclosure provides a method of providing off-peak energy storage. Mobile storage is provided for collecting biogas produced from one or more biogas plants, each of which is connected to a biogas power plant having at least one electric generator. During one or more off-peak times at least some of the biogas is diverted away from at least one of the electric generators and to mobile storage compression that compresses biogas that is fed to the mobile storage. The compressed biogas in the mobile storage is delivered to a processing facility that: (i) processes at least some of the biogas, the processing comprising capturing carbon dioxide and producing biomethane, (ii) provides at least some of the biomethane to a natural gas distribution system having interconnected storage, and (iii) provides at least some of the captured carbon dioxide for beneficial use.

Description

OFF-PEAK ENERGY STORAGETECHNICAL FIELD

[0001] The present disclosure relates generally to the renewable energy field, and more specifically to off-peak energy storage where biogas is diverted from power production and provided for fuel production.BACKGROUND

[0002] As the world strives to achieve net zero targets, the decarbonization of electricity and transportation fuels becomes imperative. Renewable electricity, produced from renewable energy sources such as sun, wind, water, or biomass (e.g., via biogas), is expected to play a crucial role in this transition.

[0003] Increasingly, renewable electricity produced from solar and / or wind power is fed into power grids. However, despite the environmental benefits thereof, these energy sources are intermittent and their variable and unpredictable nature can introduce challenges for power grid operators (e.g., who strive to balance supply and demand). For example, this intermittency often leads to periods of excess electricity supply, resulting in low or even negative electricity prices.

[0004] 0ne approach to managing excess electricity is to provide off-peak energy storage. In general, this approach has involved storing energy from excess electricity (e.g., at off-peak times) so that it can be used at a later time (e.g., at peak times). For example, energy from excess electricity can be stored via batteries (e.g., lithium ion or flow), pumped hydro storage, thermal energy storage, compressed air energy storage, flywheel energy storage, etc. Unfortunately, such approaches often face challenges related to scalability, long-term storage, topographical limitations, and / or economic efficiency, limiting their effectiveness in balancing supply and demand over extended periods.

[0005] Another type of off-peak storage that is increasingly proposed is power-to-fuel technology. In general, this approach involves storing the energy from excess electricity as chemical energy in a fuel (e.g., a gas such as hydrogen or methane, or a liquid such asmethanol or diesel). Typically, this is achieved by splitting water (H2O) into hydrogen (H2) and oxygen (O2) via electrolysis. The hydrogen can be stored directly (e.g., introduced into a natural gas network or fed to a gas storage facility), and / or can be converted to another fuel (e.g., methane, methanol, ammonia, gasoline, kerosene, diesel, etc.). Advantageously, such fuels are relatively easy to store (e.g., for a longer term, at a larger scale, and / or more economically than electricity). Unfortunately, the technology, which typically relies on electrolysers, can be costly, inefficient, and / or challenging to implement on a commercial scale.SUMMARY

[0006] The present disclosure relates to off-peak energy storage, wherein rather than storing excess electricity, biogas is diverted from power production and the energy thereof is stored in another fuel (e.g., biomethane, hydrogen, methanol, ammonia, etc.). Advantageously, since this off-peak energy storage does not necessarily require electrolysis, it can be more efficient and / or have reduced carbon emissions (e.g., relative to power-to-fuel technology). Furthermore, it can help manage the supply and demand of electricity in power grids with biogas, and / or can be beneficial for biogas producers and / or biogas power producers.

[0007] According to one aspect of the instant invention there is provided a method of providing off-peak energy storage, the method comprising: providing mobile storage for collecting biogas produced from one or more biogas plants, each of the one or more biogas plants connected to a biogas power plant having at least one electric generator for producing electricity from biogas, at least some of the electricity fed into a power grid; diverting, or arranging for the diversion of, the biogas away from at least one of the electric generators and to mobile storage compression during one or more off-peak times, thereby reducing an amount of electricity fed into the power grid during the one or more off-peak times, wherein biogas compressed by the mobile storage compression is fed into the mobile storage; delivering the compressed biogas in the mobile storage to a processing facility that: (i) processes at least some of the delivered biogas, the processing comprising capturing carbon dioxide and producing biomethane, (ii) provides at least some of the biomethane to a naturalgas distribution system having interconnected storage, and (iii) provides at least some of the captured carbon dioxide for beneficial use.

[0008] According to one aspect of the instant invention there is provided a method of providing off-peak energy storage, the method comprising: collecting biogas produced from at least one biogas plant, the at least one biogas plant connected to a biogas power plant, the biogas power plant having at least one electric generator for converting at least some of the biogas to electricity and adapted to feed the electricity into a power grid; at one or more peak times, feeding at least some of the collected biogas to the biogas power plant and operating the biogas power plant at or near capacity; at one or more off-peak times, diverting at least some of the collected biogas away from at least one of the electric generators and to mobile storage compression, thereby reducing an amount of electricity fed into the power grid during off-peak times; compressing the diverted biogas and feeding the compressed gas to mobile storage; providing the mobile storage containing the compressed biogas for transport to a processing facility that: (i) processes at least some of the biogas transported in the mobile storage, the processing comprising capturing carbon dioxide and producing biomethane, (ii) provides at least some of the biomethane to a natural gas distribution system having interconnected storage, and (iii) provides at least some of the captured carbon dioxide for beneficial use.

[0009] According to one aspect of the instant invention there is provided a method of providing off-peak energy storage, the method comprising: collecting biogas produced from at least one biogas plant, the at least one biogas plant connected to a biogas power plant, the biogas power plant having at least one electric generator for converting at least some of the biogas to electricity and adapted to feed the electricity into a power grid; at one or more peak times, feeding at least some of the collected biogas to the biogas power plant and operating the biogas power plant at or near capacity; at one or more off-peak times, diverting at least some of the collected biogas away from at least one of the electric generators and to mobile storage compression, thereby reducing an amount of electricity fed into the power grid during off-peak times; compressing the diverted biogas and feeding the compressed gas to mobile storage; providing the mobile storage containing the compressed biogas for transport to a processing facility that: (i) processes at least some of the biogastransported in the mobile storage to produce fuel, the processing comprising capturing carbon dioxide; (ii) stores the fuel; and (iii) provides at least some of the captured carbon dioxide for beneficial use.BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Non-limiting and non-exhaustive embodiments of the present disclosure are described with reference to the following description and accompanying drawings, in which:

[0011] FIG. 1 is a simplified schematic diagram of biogas power production;

[0012] FIG. 2 is a simplified schematic diagram for discussing various embodiments of the present disclosure;

[0013] FIG. 3 is a simplified schematic diagram showing different scenarios of producing hydrogen via electrolysis; and

[0014] FIG. 4 is a simplified schematic diagram showing a scenario where hydrogen is produced without electrolysis.

[0015] It should be noted that the figures may or may not be drawn to scale, and that like reference numerals refer to like elements throughout the drawings unless otherwise specified.DETAILED DESCRIPTION

[0016] Biogas is a renewable source of methane, the primary compound in natural gas.Biogas is typically formed from the breakdown of organic matter in low oxygen conditions (e.g., via anaerobic digestion). For example, biogas is commonly produced at landfills, wastewater plants, or anaerobic digesters that are fed one or more feedstocks (e.g., biomass such as manure, source-separated organics, agricultural residues, energy crops, etc.).

[0017] Biogas collected from its source is a gas mixture that is predominately methane (CH4) and carbon dioxide (CO2), and is often saturated with water (H2O). For example, depending on its source, raw biogas typically has a methane content between about 45% and about 75% (e.g., average between about 60 and about 65%), a carbon dioxide content between about25% and about 55% (e.g., average between about 35% and about 40%), on a dry basis. In addition, depending on the source of the biogas, raw biogas often contains relatively small amounts of other compounds such as hydrogen sulfide (H2S), ammonia (NH3), nitrogen (N2), oxygen (O2), hydrogen (H2), siloxanes, and / or Volatile Organic Compounds (e.g., limonene and / or other terpenes).

[0018] As a result of its composition, raw biogas has a calorific value that is low (e.g., typically between about 15 MJ / m3and about 30 MJ / m3, and often between about 20 MJ / m3and about 25 MJ / m3) relative to natural gas (e.g., about 39 MJ / m3). The low calorific value of raw biogas can be increased by subjecting biogas to biogas upgrading, wherein carbon dioxide, and often other non-methane compounds, are removed to produce upgraded biogas. When raw biogas is processed to produce upgraded biogas that is substantially interchangeable with natural gas, the upgraded biogas is referred to as biomethane.

[0019] 0ne common use of biogas is the production of electricity. For example, consider the schematic diagram illustrated in Fig. 1, wherein biogas produced from a biogas plant 10 is fed to biogas power plant 20, wherein it is converted to electricity, which is fed to a power grid 30.

[0020] Since it is generally more economical to operate power plants with substantially constant production levels, the biogas power plant 20 is operated as a baseload power plant. The term “baseload biogas power plant,” as used herein, refers to a biogas power plant whose production level is not altered to help balance supply and demand of the power grid (e.g., has a substantially constant production level that is used to meet baseload electricity demands of the power grid). In general, baseload biogas power plants are sized in dependence upon the size of the biogas plant(s) to which they are connected. For example, as biogas plants typically produce biogas continuously (e.g., at a substantially constant rate), baseload biogas power plants are often sized so as to be able to convert most or all of the biogas that is being produced to electricity (e.g., at a proportional rate).

[0021] Advantageously, the electricity produced from biogas power plants is renewable, and thus can complement the renewable electricity produced from intermittent renewable energy sources, such as wind and solar. Unfortunately, the production of electricity from biogaspower plants can be relatively expensive and its’ commercially viability can be dependent on electricity prices and / or available incentives (e.g., subsidies, guaranteed pricing, government funding, etc.). For example, in order to incentivize renewable power installations in Germany, feed-in tariffs were introduced with the country’s Renewable Energy Act (EEG) in about 2000, thereby providing guaranteed support for power plant operators for about 20 years.

[0022] As a result of various incentives, the number of biogas plants, and associated biogas power plants, has grown. However, while the number of biogas plants continues to grow (e.g., in 2023 there were almost 20,000 biogas plants in Europe), an increasing number of older biogas power plants (e.g., baseload biogas power plants) are being, or are expected to be, phased out and / or repurposed (e.g., as they near the end of their 20 renumeration period). For example, in addition to the increasing maintenance costs associated with older biogas power plants, there has been a general shift in the market (e.g., lower profits due to more renewable electricity available from solar and wind power plants, lower / fewer incentives to produce power from biogas, and / or more incentives to produce biomethane from biogas).

[0023] 0ne way in which older biogas power plants can be repurposed is to replace the equipment for power generation with equipment for biogas upgrading in order to produce biomethane (e.g., which can be compressed and distributed via a natural gas distribution system). In such cases, the biogas power plant is typically decommissioned, rather than used to produce heat and / or power for the biogas production and / or biogas upgrading because, with the relatively high cost of biogas upgrading, it generally makes more economic sense to feed all of the biogas to the biogas upgrading and to run it continuously (e.g., with electricity for the biogas production and upgrading being obtained from the power grid). Unfortunately, this option is not always attractive for the biogas producer and / or biogas power producer, even with government incentives (e.g., as a result of capital investment, operating costs associated with the small scale of many biogas plants, required expertise, and / or location relative to a natural gas distribution system). Furthermore, when a biogas upgrading plant is installed, the upgraded biogas is not necessarily used for power production (e.g., while the biomethane could be used for power production, it is typically more costly to upgrade thebiogas for power production than to use raw or partially purified biogas for power production).

[0024] Another way in which older biogas power plants can be repurposed is to convert them to a flexible biogas power plant (e.g., convert them from a baseload power plant to a dispatchable power plant). Biogas is one of the few dispatchable renewable energy technologies, and using it in a dispatchable power plant (e.g., which produces electricity at a variable rate and / or can shift electricity production to peak times) allows the biogas to help balance supply and demand of the power grid. In general, converting a baseload biogas power plant to a dispatchable biogas power plant requires investment in additional gas storage and installed power capacity (e.g., the installed capacity of a dispatchable biogas power plant can be two times higher than the corresponding baseload biogas power plant). Unfortunately, this option is also not always attractive for the biogas producer and / or biogas power producer, even with government incentives. For example, in addition to challenges related to intermittent use, there can be higher maintenance costs and / or space requirements associated with the additional storage and / or power generation equipment.

[0025] The present disclosure relates to off-peak energy storage, where rather than solely focusing on storing excess electricity, electricity production from biogas is backed off during one or more off-peak times, and the biogas that would have been converted to electricity is instead converted to another fuel (e.g., biomethane, hydrogen, methanol, and / or ammonia). The resulting fuel can be stored and used to generate renewable electricity at a later time (e.g., at one or more peak times), or can be used in other sectors (e.g., transportation or chemical).

[0026] Advantageously, this is achieved by diverting biogas away from biogas power production and to mobile storage compression, where the biogas is compressed and fed into mobile storage so that it can be transported to fuel production (e.g., biomethane, hydrogen, methanol, and / or ammonia production). Since the fuel production is off-site from the biogas plant and / or biogas power plant, there is reduced capital investment for the biogas producer and / or biogas power producer (e.g., relative to converting the biogas power production to onsite biomethane production). For example, investments for this approach can include mobilestorage and mobile storage compression (e.g., some or all of which may be provided by the fuel producer). In addition, it can provide additional revenue for the biogas producer and / or biogas power producer. For example, there can be additional revenue from the sale of the diverted biogas and / or possibly from capacity payments.

[0027] Further advantageously, since the biogas is diverted away from biogas power production at certain times (e.g., during one or more off-peak times) and / or in certain amounts (e.g., various fractions of biogas can be diverted), the biogas power plant can still produce renewable power used for dynamically managing the supply and demand of the power grid and / or for the process (e.g., compressing the diverted biogas for transport). Since the biogas power plant is not decommissioned, this approach can safeguard existing investments (e.g., baseload power generation equipment).

[0028] Yet further advantageously, since the fuel production can be a centralized processing facility that receives biogas from multiple other sources (e.g., other converted baseload biogas power plants, landfills, biogas plants, etc.), the fuel production can benefit from the economies of scale, and thus can produce the fuel more cost effectively, more efficiently, and / or with reduced carbon emissions.

[0029] Referring to Fig. 2, various embodiments of the present disclosure include biogas production 40 (e.g., where biogas is produced from a biogas plant), biogas power production 50 (e.g., where at least some of the biogas produced from the biogas plant is converted to electricity), feeding electricity into a power grid 60 (e.g., where at least some of the electricity produced at the biogas power plant is fed into a power grid), mobile storage compression 70 (e.g., where at least some of the biogas produced from the biogas plant is compressed and fed into mobile storage), mobile storage transport 80 (e.g., where biogas in mobile storage is transported to fuel production by vehicle), and fuel production 90 (e.g., where the biogas transported in mobile storage is processed to produce one or more fuels such as biomethane, hydrogen, methanol, ammonia, etc.).

[0030] In general, the biogas produced from biogas production 40 is dynamically directed between biogas power production 50 and mobile storage compression 70 (e.g., where the ratio of the flow rate of biogas fed to biogas power production to the flow rate of biogas fedto mobile storage compression varies over an hour, day, month, or year). For example, in one embodiment, the method includes diverting at least some of the biogas produced from biogas production 40 away from biogas power production 50 and to mobile storage compression 70 during one or more off-peak times, and feeding at least some of the biogas produced from biogas production 40 to biogas power production 50 during one or more peak times. The diversion of at least some of the biogas away from power production (e.g., away from at least one of the electric generators) and to mobile storage compression reduces an amount of electricity fed into the power grid during the one or more off-peak times (i.e., relative to if the biogas was fed to power production).

[0031] Advantageously, this facilitates the biogas being used to help dynamically manage the supply and demand of electricity within the power grid, without having to install the storage and / or increased power capacity that otherwise would be required to make the biogas power plant dispatchable. In addition, this embodiment can provide various benefits for the biogas producers and / or biogas power producers (e.g., can provide another option for certain biogas power plants that are nearing the end of their renumeration period). For example, it can increase profits by facilitating the production of electricity from biogas at times when the electricity prices are highest, can increase profits by facilitating the use of the biogas for biomethane production without having to install biogas upgrading equipment, and / or can reduce the risk of the biogas power plant being decommissioned.

[0032] In one embodiment, the fuel production 90 includes biogas processing, where the biogas processing includes biogas upgrading (e.g., produces biomethane) and capturing carbon dioxide (e.g., to produce at least one carbon dioxide-rich stream). In one embodiment, the biogas processing produces biomethane that is fed into a natural gas distribution system having interconnected storage. In one embodiment, biomethane derived from the biogas is withdrawn from the natural gas distribution system for power production. In one embodiment, at least some of the captured carbon dioxide (e.g., from a carbon dioxide-rich stream) is provided for beneficial use. In one embodiment, the beneficial use is a greenhouse gas reduction process (e.g., which reduces the carbon intensity of the process, the biomethane, and / or fuel produced from the biomethane).Biogas production

[0033] The biogas is produced from at least one biogas plant.

[0034] The term “biogas,” as used herein, refers to a gas mixture that contains methane and is produced from the anaerobic digestion of organic matter. The term “biogas,” as used herein, can encompass raw or partially purified biogas, but does not encompass “biomethane” unless otherwise indicated.

[0035] The term “raw biogas,” as used herein, refers to biogas having a composition that is substantially the same as when it was collected from its source, on a dry basis. For example, while the term “raw biogas” can encompass biogas that has been filtered (e.g., to remove particulates) and / or has been subjected to water removal (e.g., dried), it typically does not encompass biogas that is has been subjected to one or more purification steps provided to remove one or more non-methane compounds other than water.

[0036] The term “partially purified biogas,” as used herein, refers to biogas that has been subjected to one or more purification steps provided to remove one or more non-methane compounds other than water, but still has a methane content less than 90%, on a dry basis. For example, the term “partially purified biogas” encompasses biogas produced by removing water from raw biogas, and subjecting the resulting dried biogas to hydrogen sulfide removal (e.g., via adsorption by active carbon).

[0037] The term “biomethane,” as used herein, refers to biogas that has been subjected to processing that includes biogas upgrading (e.g., one or more purification steps provided to remove one or more non-methane compounds) and is substantially interchangeable with natural gas (e.g., can be injected into a natural gas distribution system). In general, biomethane has a methane content of at least 90%, preferably at least about 95%, and more preferably at least about 97% (e.g., 100%). Optionally, the processing of the biogas can include adding an odorant and / or gas having a relatively high calorific value (e.g., natural gas or propane).

[0038] The percentages used to quantify composition and / or a specific content, as used herein, are expressed as mol%, unless otherwise specified. More specifically, for gasmixtures, they are expressed by mole fraction at standard temperature and pressure (STP), which is equivalent to volume fraction, unless otherwise specified. As will be appreciated by those skilled in the art, the composition of gases material (e.g., or parts thereof) can be measured using any suitable technology or combination of technologies (e.g., using gas chromatography with a flame ionization detector and / or mass spectrometer).

[0039] The term “biogas plant,” as used herein, refers to a facility (e.g., a place, amenity, and / or equipment) provided for producing biogas. For example, a biogas plant can be a landfill adapted to collect landfill gas produced therein, or a biogas plant can be one or more digesters fed manure and / or agricultural residue (e.g., installed at a farm).

[0040] The term “digester”, as used herein, refers to any receptacle (e.g., vessel and / or space) in which at least part of the anaerobic digestion occurs. For example, each digester can be a holding tank, or other contained volume, such as a covered lagoon or a sealable structure, designed to facilitate the breakdown of organic matter by microorganisms under anaerobic or low oxygen conditions and the collection of biogas. If more than one digester is used, the digesters can be connected in series and / or in parallel.

[0001] In general, the biogas produced at the biogas plant(s) can be derived from any suitable feedstock or combination of feedstocks. For example, in one embodiment, the biogas is derived from: (i) energy crops (e.g., switchgrass, sorghum, etc.); (ii) residues, byproducts, or waste from the processing of plant material in a facility, or feedstock derived therefrom (e.g., sugarcane bagasse, sugarcane tops / leaves, corn stover, etc.); (iii) agricultural residues (e.g., wheat straw, com cobs, barley straw, com stover, etc.); (iv) forestry material; (v) manure (e.g., dairy, swine, or chicken manure); (vi) organic fraction of municipal waste; and / or (vii) food or yard waste collected from households, restaurants, supermarkets, food-processing companies, schools, businesses, etc.

[0042] The biogas produced from the biogas plant(s) can be collected (e.g., provided via a pipe system that includes one or more pipes) and fed to biogas power production and / or mobile storage compression.Biogas Power Production

[0043] At least some of the biogas is fed to a biogas power plant, wherein at least some of the biogas is converted to electrical power (i.e., electricity) that is fed to a power grid.

[0044] The term “biogas power plant”, as used herein, refers to a facility (e.g., a place, amenity, and / or equipment) that converts biogas (i.e., raw or partially purified biogas) to electricity, and optionally to heat, and is adapted to feed the electricity to a power grid. For example, a biogas power plant can be a combined heat and / or power (CHP) plant.

[0045] Each biogas power plant will have one or more electric generators (e.g., between 1 and 12 electric generators). The term “electric generator,” as used herein, refers to a device that converts motion-based power (potential and kinetic energy) and / or fuel-based power (chemical energy) into electric power (electricity). For example, electric generators can be turbine-driven electric generators, engine-driven electric generators, combined cycle generators, fuel cells, and / or CHP generators.

[0046] Preferably, each electric generator is part of a generator set (gen-set). The term “generator set,” as used herein, refers to a power generation unit (e.g., portable or stationary) that includes a combustion engine (e.g., for producing mechanical energy) and an electric generator for converting the mechanical energy into electrical energy (i.e., electricity). As biogas has a low calorific value relative to natural gas, generator sets used in biogas power plants are often adapted accordingly (e.g., it is not always practically possible to use generator sets designed for natural gas with biogas without modification). While the combustion engine can be any suitable engine (e.g., a reciprocating gas engine), biogas generator sets often include an internal combustion engine, such as a gas engine (e.g., Otto systems that combust the biogas), or a gas turbine (e.g., microturbine). Alternatively, a biogas generator set can include a diesel engine (e.g., the combusts the biogas in dual fuel mode).

[0047] Each biogas power plant is connected to one or more biogas plants via one or more conduits (e.g., a single pipe or multiple interconnected pipes) so that the biogas produced from the biogas plant(s) can flow to the biogas power plant (e.g., when appropriate valves are open). In general, the biogas power plant can be connected directly to the biogas plant(s) or indirectly to the biogas plants (e.g., with one or more processing units therebetween). Forexample, in some cases it can be advantageous to provide a holding tank for storing pressurized biogas (e.g., to improve operation of the biogas power plant) and / or to provide one or more purification units (e.g., to provide partial purification of the biogas), upstream of the biogas power plant.

[0048] Providing partial purification upstream of biogas power production can be beneficial in some cases. For example, some compounds such as water, hydrogen sulfide, siloxanes, and / or VOCs can produce environmentally harmful emissions when combusted and / or can potentially damage the combustion equipment. Accordingly, biogas fed to biogas power plants is often subjected to a partial purification the removes water, hydrogen sulfide, siloxanes, and / or VOCs, if present in a significant amount. While the partial purification can include carbon dioxide removal, it can be advantageous if it is not exhaustive (e.g., economically). For example, providing a membrane system for removing part of the carbon dioxide can reduce mobile compression costs, with minimal additional costs. In some other cases, a partial purification is not necessary (e.g., some anaerobic digestions do not produce a significant amount of hydrogen sulfide and / or siloxanes). For example, in some cases, small amounts of oxygen can be introduced into the headspace of an anaerobic digester, such that that the hydrogen sulfide is oxidized by microorganisms, and such that the biogas collected therefrom does not need to be further desulfurized prior to biogas power production.

[0049] In general, each biogas power plant can be co-located with one or more biogas plants (e.g., installed at the same farm) and / or can be located at a different location than the biogas power plant(s). In the latter case, if the biogas is fed into a holding tank and / or is subjected to a partial purification, the corresponding equipment can be located closer to the biogas plant(s) or closer the biogas power plant.

[0050] Each biogas power plant is adapted to feed electricity produced therefrom into a power grid. Optionally, some of the electricity produced from the biogas power plant(s) is used for the process. For example, in one embodiment, some of the electricity produced from the biogas power plant(s) is used for biogas production (e.g., heating an anaerobic digester), for partial purification of the biogas, and / or for compression of the biogas (e.g., mobile storage compression).Power Grid

[0051] At least some of the electricity produced from the biogas power plant(s) is fed to a power grid.

[0052] The term “power grid”, as used herein, refers to a network of power lines and associated equipment used to transmit and distribute electricity (e.g., over a certain geographical location), where the electricity is produced from multiple power plants and is consumed by multiple users, and where the power grid is managed / operated via one or more control centers.

[0053] As the users of the power grid (e.g., residential, commercial, and industrial customers) have varied power needs, the electricity demand (also termed load) can vary over the course of a day, month, year (e.g., a power grid can be associated with a load profile that has one or more peaks and one or more valleys, and that varies by the season). For example, without being limiting, peak demand, which generally occurs when the users of the power grid consume the most electricity, often occurs between 6 am and 7 am, between 5 pm and 9 pm, and / or during the hottest part of the afternoon in summer (e.g., depending on the geographical location of the power grid). While load profiles often include peaks and valleys, the electricity demand generally doesn’t drop to zero; rather the power grid typically has a minimum load during the year (e.g., termed baseload).

[0054] To ensure the stable and reliable operation of power grids, grid operator(s) and / or control center(s) continuously monitor and manage the flow of electricity (e.g., in real time) in order to balance supply and demand. The balance of supply and demand can be achieved, for example, by supply control (e.g., using dispatchable power plants) and / or load management (e.g., time-of-use pricing, load shedding, etc.).

[0055] Power grids can have one or more peak times and one or more off-peak times. In general, “peak time” refers to a time period that the electricity demand and / or electricity price associated with the power grid is and / or is expected to be equal to or above a certain threshold, whereas the term “off-peak time” refers to a time period that the electricity demand and / or electricity price associated with the power grid is and / or is expected to bebelow a certain threshold. As will be appreciated by those skilled in the art, different power grids can have different thresholds.

[0056] For purposes herein, an “off-peak time” is when any one or any combination of the following is true: a) the time is within a time range identified as off-peak by the power grid operator (e.g., nights from 12 am to 6 am); b) the time coincides with a time where the spot electricity price (i.e., the settled wholesale spot price for electricity as provided by the grid operator for the respective market price interval (e.g., 5 minutes) of the power grid servicing the facility) is below the average spot electricity price of the past 3 months; c) the time coincides with a time where the power grid operator and / or control center(s) has indicated that additional electricity should not be produced (e.g., by dispatchable power plants).

[0057] For purposes herein, “peak time” encompasses any time that is not an off-peak time. As will be appreciated by those skilled in the art, off-peak times and / or peak times of a power grid can span several minutes, hours, days, or months.Mobile Storage Compression

[0058] At least some of the biogas is diverted away from biogas power production and to mobile storage compression.

[0059] The term “mobile storage,” as used herein, refers to any vessel (e.g., tank) or combination of vessels (e.g., interconnected vessels), which is suitable for holding pressurized biogas, and which can be moved from one location to another by vehicle (e.g., a truck, ship, rail car). Without being limiting, such vessel(s) can be of any suitable shape and / or fabricated from any suitable material (e.g., such as those used to hold pressurized natural gas). For example, the mobile storage can include one or more steel cylinders or one or more composite cylinders (e.g., lined with metal or polymer).

[0060] While the mobile storage can be integrated with the vehicle that transports it (e.g., the mobile storage can be part of a compressed natural gas (CNG) tank truck), it can be advantageous if the mobile storage, or a unit that houses / supports the mobile storage, can be decoupled from the vehicle (e.g., the mobile storage can be mounted to a trailer, skid, or shipping container that can be decoupled from a truck). This can, for example, allow a trailercontaining the mobile storage to be parked (without a truck) so that it can be filled as needed, and then when full, coupled to a truck for transport. Advantageously, this can reduce costs and / or reduce the need for larger holding tanks.

[0061] The term “mobile storage compression,” as used herein, refers to compression conducted to pressurize the biogas for transport in the mobile storage (e.g., is provided upstream of mobile storage). Mobile storage compression can be conducted using any compression system (e.g., containing one or more multistage compressors) suitable for compressing the biogas. The compression system can be mobile (e.g., provided with the mobile storage) or stationary (e.g., installed close to the biogas plant(s) and / or to the biogas power plant). As the mobile storage compression and / or the biogas power production can produce heat, it may be advantageous when the biogas plant and / or partial purification plant is sufficiently close to use the generated heat (e.g., for heating the anaerobic digester).

[0062] In general, the mobile storage compression pressurizes the biogas to pressures suitable for transport (i.e., at least to 100 psig). For example, in one embodiment, the biogas (e.g., which may be at pressures less than 14 psig, such as between 2 and 4 psig) is compressed to pressures as high as 1000 psig, 1200 psig, 1500 psig, 2000 psig, 3000 psig, 3600 psig, or higher.

[0063] The diversion of the biogas away from the biogas power production and to mobile storage compression can be conducted using any suitable technology (e.g., appropriate valves and pipes) and can be provided at any suitable location (e.g., at or near the biogas plant and / or at or near the biogas power plant). If the biogas is subjected to a partial purification or is fed into a holding tank upstream of the biogas power production, the diversion of the biogas can be upstream or downstream thereof. In some cases, it can be advantageous to provide the diversion downstream of any partial purification (e.g., if hydrogen sulfide should be removed prior to transport for regulatory reasons and / or if a small amount of carbon dioxide should be removed to simplify loading, unloading, and / or transport of the biogas).

[0064] The biogas can be directed between biogas power production and mobile storage compression such that all of the biogas goes to the biogas power production or all of the biogas goes to mobile storage compression, or such that the flow of biogas is split betweenbiogas power production and mobile storage compression. In practice, even when it is generally beneficial (e.g., economically) to feed all of the biogas to mobile storage compression, it can be advantageous to feed some of the biogas to biogas power production (e.g., in order to produce electricity for the mobile storage compression and / or biogas production). For example, in one embodiment, at least about 10%, at least about 15%, at least about 20% of the biogas, on volume basis, is continuously fed to biogas power production. In such cases, when the biogas power plant has multiple generator sets, one or more generator sets may be idle, while one or more are operating. In general, the biogas is dynamically directed between biogas power production and mobile storage compression such that the ratio of the flow rate of biogas to biogas power production to the flow rate of biogas to mobile storage compression varies over an hour, day, month, or year.

[0065] In general, it can be advantageous when at least some of the biogas is diverted away from the biogas power production, and to mobile storage compression, during one or more off-peak times (e.g. for all or any part of an off-peak time period). In one embodiment, at least some of the biogas (e.g., at least two thirds of the flow) is diverted away from biogas power production, and to mobile storage compression, when electricity prices are below the average spot electricity price over the past three months. In one embodiment, at least some of the biogas (e.g., at least two thirds of the flow) is diverted away from biogas power production, and to mobile storage compression, when electricity prices are negative. In one embodiment, at least some of the biogas (e.g., at least two thirds of the flow) is diverted away from the biogas power production, and to mobile storage compression, when the power grid operator / controller indicates that dispatchable electricity is not needed. In one embodiment, at least some of the biogas (e.g., at least two thirds of the flow) is diverted away from biogas power production, and to mobile storage compression, at one or more times between 12 am and 6 am. In one embodiment, at least some of the biogas (e.g., at least two thirds of the flow) is diverted away from biogas power production, and to mobile storage compression, when weather conditions result in a relatively high amount of electricity being produced from solar and / or wind power.

[0066] Alternatively, or additionally, it can be advantageous when at least some of the biogas is fed to biogas power production (and is not diverted to mobile storage compression) duringone or more peak times (e.g. for all or any part of a peak time period). In one embodiment, at least some of the biogas (e.g., at least two thirds of the flow) is fed to biogas power production (and not to mobile storage compression) when spot electricity prices are equal to or above the average spot electricity price from the past three months. In one embodiment, at least some of the biogas (e.g., at least two thirds of the flow) is fed to biogas power production (and not to mobile storage compression) when the spot electricity prices are above the 70th, 75th, 80th, or 85thpercentile of electricity prices from the past three months. In one embodiment, at least some of the biogas (e.g., at least two thirds of the flow) is fed to biogas power production (and not to mobile storage compression) when the power grid operator indicates that dispatchable electricity is needed. In one embodiment, at least some of the biogas (e.g., at least two thirds of the flow) is fed to biogas power production (and not to mobile storage compression) at one or more times between 5 pm and 9 pm (e.g., in the winter). In one embodiment, at least some of the biogas (e.g., at least two thirds of the flow) is fed to biogas power production (and not to mobile storage compression) when weather conditions and / or time of day result in a relatively low amount of electricity being produced from solar and / or wind power.

[0067] In some embodiments, at least some of the biogas (e.g., at least two thirds of the flow) is diverted away from biogas power production, and to mobile storage compression, during one or more off-peak times and during one or more peak times. For example, it may be advantageous to divert the biogas to mobile storage compression during one or more peak times when the supply already meets or is close to meeting the demands on the power grid.

[0068] In one embodiment, the biogas is directed between the biogas power production and mobile storage compression such that at one or more peak times the biogas power plant is operated at at least 80% of the capacity.

[0069] In one embodiment, at least some of the biogas (e.g., at least two thirds of the flow) is diverted away from biogas power production, and to mobile storage compression, for at least 50% of the time, at least 60% of the time, or at least 70% of the time, averaged over a year.

[0070] In one embodiment, the biogas is directed between the biogas power production and mobile storage compression such that the biogas power plant produces more electricityelectricity for the power grid than for mobile compression less than 50% of the time, less than 40% of the time, or less than 30% of the time, averaged over a year.

[0071] At least some of the biogas that is compressed via the mobile storage compression is fed into mobile storage. When the mobile storage is full (e.g., filled to or close to the desired pressure), it is transported for fuel production.Fuel Production

[0072] At least some of the biogas transported in the mobile storage is fed to a processing facility that produces fuel or an intermediate to one or more fuels (e.g., biomethane, hydrogen, methanol, ammonia, gasoline, kerosene, diesel etc.).

[0073] Since at least some of the fuel produced is derived from the transported biogas, the fuel produced can be at least partially renewable. Advantageously, this at least partially renewable fuel can be used to produce electricity for the power grid, or can be used in another sector (e.g., can be a renewable transportation fuel or a renewable feedstock for chemical production). The term “derived from”, as used herein, encompasses the terms "originated from," "obtained from," "obtainable from," "isolated from," “produced from,” and "created from."

[0074] Since the transported biogas was diverted from biogas power production, the production of the fuel derived from the transported biogas is a type of “off-peak energy storage,” regardless of whether the fuel is used to generate renewable electricity at a later time (e.g., at one or more peak times), regardless of whether the biogas is diverted away from biogas power production during off-peak and / or peak times, and / or regardless of whether the fuel is stored for a certain length of time. Advantageously, this off-peak energy storage is provided without having to convert the biogas to electricity, and thus can be simpler and / or more efficient than off-peak storage wherein energy from excess electricity is stored.

[0075] In a preferred embodiment, the processing facility provides biogas upgrading. As will be appreciated by those skilled in the art, “biogas upgrading” includes one or more processes that separate the methane in biogas from one or more non-methane compounds in the biogas (e.g., carbon dioxide, water, hydrogen sulfide, ammonia, nitrogen, oxygen, siloxanes, and / orVOCs), and can be achieved using known technology or any combination of known technologies (e.g., chemical and / or physical). For example, water can be removed by cooling, compression, absorption, adsorption, and / or coalescing filtration. Hydrogen sulfide can be removed by adsorption on activated carbon (e.g., impregnated activated carbon such as ZnO impregnated carbon), adsorption on molecular sieve, adsorption using iron oxides (e.g., iron oxide impregnated wood chips (iron sponge)), iron oxide pellets, or proprietary iron-oxide media), physical absorption (e.g., water scrubbing), chemical absorption (e.g., NaOH washing), and / or biofilters or biotrickling filters. Siloxanes can be removed by filtration (e.g., activated alumina, activated carbon, graphite filtration, or silica gels, which absorb siloxanes from biogas), by condensation or cryogenic techniques, using synthetic resins, using liquid absorbents (e.g., Selexol™), using membranes, and / or using biological processes. Nitrogen can be removed by pressure swing absorption (PSA), membranes, and / or cryogenic systems. Oxygen can be removed by catalytic oxidation, membranes, or low pressure PSA. Carbon dioxide can be removed by absorption (e.g., water scrubbing, organic physical scrubbing, chemical scrubbing), PSA, membrane permeation, and / or cryogenic upgrading.

[0076] Feeding at least some of the biogas transported in the mobile storage to a processing facility that has biogas upgrading (e.g., carbon dioxide and / or nitrogen removal) is advantageous because the biogas can be upgraded without the biogas producer and / or biogas power producer having to invest and / or install the biogas upgrading equipment. In addition, when the processing facility is a centralized processing facility that receives biogas from multiple biogas plants and / or biogas power plants, the biogas upgrading can benefit from the economies of scale, can benefit from substantially constant supply of biogas, and / or can facilitate centralized carbon capture and sequestration (CCS).

[0077] In one embodiment, the processing facility includes a biogas upgrading system, which produces upgraded biogas (e.g., biomethane), and one or more units for processing the upgraded biogas. For example, such processing can include compression (e.g., for transport), odorization (e.g., to ensure the upgraded biogas is readily detectable to the human nose), and / or blending up (e.g., where the upgraded biogas is mixed with a gas having a relatively high calorific value).

[0078] Advantageously, when the processing facility includes a biogas upgrading system and produces biomethane, the biomethane can be stored and / or transported using technology commonly used for natural gas. In one embodiment, the biomethane that is produced from the processing facility is introduced into a natural gas distribution system (e.g., for storage and / or for transport as a fungible batch).

[0079] When biomethane is provided as a fungible batch via a natural gas distribution system, a quantity of biomethane (e.g., in MJ) is injected into the natural gas distribution system at one location, and an equal quantity of gas, or less (e.g., in MJ), is withdrawn from the natural gas distribution system at another location, and / or another time, and is treated as the biomethane under applicable regulations (e.g., even though the withdrawn gas may not contain actual molecules from the biomethane and / or contains methane from fossil sources). In general, such treatment can be based on the transfer or allocation of the environmental attributes of the biomethane to the withdrawn gas (e.g., on a displacement basis, where transactions within the natural gas distribution system involve a matching and balancing of inputs and outputs) and / or can be evidenced through documentation (e.g., chain of custody documents, proof of sustainability, guarantees of origin, book-and-claim accounting).

[0080] In one embodiment, the biomethane that is produced from the processing facility is introduced into a natural gas distribution system (e.g., for storage and / or for transport as a fungible batch), and a gas derived from the biomethane is withdrawn from the natural gas distribution system (e.g., for power and / or fuel production). The term “gas derived from biomethane,” as used herein, encompasses any gas (e.g., withdrawn from a natural gas distribution system) that is associated with environmental attributes of the biomethane. The term “environmental attributes”, as used herein, encompasses a recognition or entitlement, in any form and any jurisdiction, associated with a product and relating to a reduction in greenhouse gas emissions resulting from such products’ use or to the renewable origin of the product itself, including, but not limited to, all environmental attributes necessary to generate credits (e.g., RINs, LCFS credits, and / or European fuel credits).

[0081] In one embodiment, the processing facility provides biogas upgrading, produces biomethane, and at least some of the biomethane produced is stored. In general, thebiomethane can be stored directly (e.g., in liquid or gaseous form in above-ground tanks), or indirectly (e.g., via injection into a natural gas distribution system having interconnected storage). For example, biomethane can be stored directly or indirectly as a compressed gas in depleted underground reservoirs in oil and / or natural gas fields, in aquifers, and / or in salt cavern formations. For purposes herein, the term “store,” with reference to biomethane, encompasses introducing the biomethane into a natural gas distribution system having interconnected storage. Advantageously, when the biomethane is stored via the injection of the biomethane into a natural gas distribution system having interconnected storage (e.g., above ground tanks and / or underground reservoirs), the biomethane can be used to help balance the supply and demand of the power grid and / or balance the supply and demand of the natural gas distribution system.

[0082] Advantageously, the diversion of the biogas from biogas power production to biomethane production (e.g., via mobile storage compression) provides off-peak energy storage that is simpler and / or more efficient than off-peak storage wherein the energy from excess electricity is stored.

[0083] Further advantageously, when the biomethane is introduced into a natural gas distribution system (e.g., having interconnected storage), gas derived from the biomethane can be withdrawn from the natural gas distribution system and used to produce at least partially renewable fuel (e.g., syngas, methanol, hydrogen, ammonia, gasoline, kerosene, and / or diesel) or another product that is at least partially renewable. The production of fuel and / or other products from methane-rich fluid (e.g., biomethane or natural gas) is well-known. For example, biomethane and / or natural gas can be converted to hydrogen via methane reforming or methane cracking. The resulting hydrogen can be introduced into a natural gas distribution system (e.g., for storage) and / or can be used to produce another fuel and / or product (e.g., methanol, ammonia, gasoline, kerosene, diesel, ethanol, propanol, dimethyl ether (DME), formaldehyde, steel, ammonia, and / or fertilizer).

[0084] While it is generally advantageous to store the energy from the diverted biogas as biomethane, in some cases it can be advantageous if the energy from the diverted biogas is stored as another fuel (e.g., syngas, methanol, hydrogen, ammonia, gasoline, kerosene, and / ordiesel). For example, if the processing facility is not in close proximity to a natural gas distribution system, it may be advantageous if the processing facility includes one or more fuel production units (e.g., producing liquid fuels, such as methanol, can be advantageous for storage and / or delivery). In general, at least one of the feeds for the fuel production is a methane-rich fluid such as raw biogas, partially purified biogas, or biomethane (e.g., the processing facility may or may not include biogas upgrading). The term “methane-rich fluid,” as used herein, refers to fluid having a methane content of at least about 35%.

[0085] In one embodiment, the processing facility provides syngas production. The term “syngas”, as used herein, refers to a gas mixture that contains hydrogen (H2) and one or more carbon oxides (e.g., carbon monoxide (CO) and / or carbon dioxide (CO2)). While syngas is predominately hydrogen and one or more carbon oxides (e.g., hydrogen in addition to the carbon oxides collectively make up more than about 50% of the gas), it can also contain unreacted feedstock (e.g., methane) and / or smaller amounts of other gases (e.g., argon and / or nitrogen). In general, the production of syngas from methane can be achieved using any known process (e.g., methane reforming).

[0086] The term “methane reforming,” as used herein, refers to one or more reactions and / or unit operations wherein methane (e.g., in a methane-rich fluid such as biogas, biomethane, and / or natural gas) is converted to syngas. In general, methane reforming can be achieved using any suitable technology or combination of technologies known in the art that can convert methane to syngas, including, but not limited to, steam methane reforming (SMR), dry methane reforming (DMR), and / or autothermal reforming (ATR).

[0087] In SMR, which is a type of catalytic reforming, methane reacts with steam at a relatively high temperature and pressure to produce the syngas. For example, SMR is often associated with the following reactions, with the main chemical reaction corresponding to Eq. (1).CH4+ H2O(g) CO + 3H2(1)CO + H2O(g) CO2 + H2 (2)CH4+ 2H2O(g) CO2+ 4H2(3)

[0088] Without being limiting, the catalyst for SMR can be nickel-based (e.g., supported on alumina or another suitable material), the operating pressure may be between about 200 psig (about 1.38 MPa) and about 600 psig (about 4.14 MPa), and the operating temperature may be between about 450°C to about 1000°C (e.g., often between about 800°C and about 925°C). SMR is often conducted in reactors that contain vertical tubes packed with the catalyst (e.g., catalyst pellets). In general, many SMR units are designed for converting natural gas to syngas (e.g. it is often advantageous if the feed to SMR does not contain an excessive amount of carbon dioxide).

[0089] In DMR, which is also a catalytic process, the methane reacts with carbon dioxide, rather than steam. For example, DMR is generally associated with the following reaction:CO2+ CH42CO + 2H2(4)

[0090] Without being limiting, the DMR catalyst may be nickel, iron, ruthenium, palladium, or platinum based. While the DMR process does not require steam, and may be conducted at lower temperatures (e.g., between about 600°C to about 800°C), it may be limited by the potential for coke formation. Dry methane reforming can be advantageous when the feedstock has a significant carbon dioxide content (e.g., is raw or partially purified biogas).

[0091] In ATR, steam methane reforming or dry methane reforming reactions are conducted along with partial oxidation reactions. Such reactions are typically conducted in a single reactor such that heat generated from the partial oxidation (e.g., in the combustion zone of the reactor) can be used in the catalytic reforming (e.g., in the reforming zone of the reactor). For example, such ATR reactions are generally associated with one of the following reactions.4CH4+ O2+ 2H2O 10H2+ 4CO (5)2CH4+ O2+ CO23H2+ 3CO + H2O (6)

[0092] Without being limiting, conventional ATR may operate at temperatures between about 750 to 1400°C. In some cases, ATR can use nearly pure oxygen (e.g., about 99.5%) for the combustion.

[0093] As will appreciated by those skill in the art, in many cases, it can be advantageous to provide sulfur removal and / or pre-reforming upstream of the reactor(s) in which the methane reforming is conducted. In addition, as will also be appreciated by those skill in the art, depending on how the syngas is to be used, it can be advantageous to provide one or more water gas shift (WGS) reactors downstream of the reactor(s) in which the methane reforming is conducted. The WGS reaction, which corresponds to the reaction in Eq. 2, consumes carbon monoxide and produces additional hydrogen. While the reforming catalysts used in methane reforming can be active with respect to the WGS reaction (e.g., gas leaving a steam reformer can be in equilibrium with respect to the WGS reaction), the conversion can be limited by relatively high temperatures. Providing one or more separate downstream WGS reactors (i.e., shift reactors) operated at a relatively low temperature can maximize the amount of hydrogen produced. In general, shift reactors may use any suitable type of shift technology (e.g., high temperature shift conversion, medium temperature shift conversion, low temperature shift conversion, sour gas shift conversion, or isothermal shift). For example, WGS reactions may be conducted at temperatures between 320-450°C (high temperature) and / or between 200-250°C (low temperature). Without being limiting, high temperature thermal shift may be conducted with an iron oxide catalyst (e.g., supported by chromium oxide), whereas low temperature thermal shift may be conducted with a Cu / ZnO mixed catalyst. For purposes herein, when one or more WGS reactors are provided, the corresponding WGS are part of the methane reforming used to produce the syngas.

[0094] In one embodiment, the processing facility includes methane reforming, and the syngas produced from methane reforming is stored and / or used to produce electricity (e.g., for the power grid during one or more peak times).

[0095] In one embodiment, the processing facility includes methane reforming, where the methane reforming is part of hydrogen production, and the hydrogen produced is stored (e.g., introduced into a natural gas distribution system) and / or used to produce electricity (e.g., for the power grid during one or more peak times).

[0096] In such hydrogen production, the syngas produced from methane reforming is subjected to one or more purification processes that separate the hydrogen from the carbonoxides and / or unreacted methane to produce a hydrogen product (i.e., fluid that is at least about 80% hydrogen). In general, such purification process(es) can be achieved using any suitable separation technology or combination of technologies. Without being limiting, some examples of separation technologies that may be suitable include, but are not limited to, gas separations based on: a) absorption, b) adsorption, c) membrane separation, d) cryogenic separation, and / or e) methanation. For example, hydrogen purification often uses absorption (e.g., based on monoethanolamine (MEA) or a methyldiethanolamine (MDEA)) or adsorption (e.g., an adsorbent bed containing molecular sieves, activated carbon, active alumina, or silica gel).

[0097] In one embodiment, the processing facility includes methane reforming, where the methane reforming is part of fuel production (e.g., to produce a fuel other than hydrogen, such as, for example, methanol, ammonia, gasoline, kerosene, and / or diesel). For example, in one embodiment, the processing facility includes methane reforming, wherein the syngas produced from methane reforming is fed to methanol production, Fischer-Tropsch fuel production, and / or gas fermentation.

[0098] Methanol production, which is well-known to those skilled in the art, is often associated with the following reaction:CO + 2H2CH3OH (7)

[0099] Without being limiting, this reaction can be carried with a zinc / chromium oxide catalyst (ZnO / Cr2Os) at temperatures between about temperatures between about 300°C and about 400°C and pressures between about 25 MPa and about 35 MPa, or can use a copper / zinc oxide / alumina catalyst (Cu / ZnO / AhOs) at temperatures between about 240°C and about 270°C and pressures between about 5 MPa and about 8 MPa.

[0100] Fischer-Tropsch processes, which are well-known to those skilled the art, are often associated with the following overall reaction, where n is an integer (e.g., between 10-20).(2n+l )H2+ nCO CnH2n+2+ nH20 (8)

[0101] Without being limiting, Fischer-Tropsch processes often use a metal catalyst (e.g., iron or cobalt) supported on a high surface area material (e.g., alumina, silica, or zeolite) along with any promotors (e.g., potassium or copper), and are often conducted at temperatures between about 150°C and about 400°C (e.g., often between about 175°C and about 250°C) and at pressures between about 0.1 MPa and about 10.1 MPa (e.g., often between about 1.5 MPa and about 4.0 MPa). Fischer-Tropsch processes can produce hydrocarbons suitable for use in gasoline, diesel, and / or aviation fuel.

[0102] Gas fermentations, which are well-known to those skilled in the art, are microbial processes that can convert syngas to various fermentation products (e.g., methanol, ethanol, propanol, butanol, acetic acid, acetate, butyric acid, etc.). Without being bound by any particular theory, some reactions that can be associated with the microbial conversion of syngas to ethanol include:6C0 + 3H2O CH3CH2OH + 4CO2(9)6H2+ 2CO2CH3CH2OH + 3H2O (10)2CO + 4H2CH3CH2OH + CO2(11)3CO + 3H2^ CH3CH2OH + H2O (12)

[0103] In general, any suitable microorganisms or other biocatalysts can be used for gas fermentation (e.g., acetogens). For example, some examples of strains that can produce ethanol from syngas are those from the genus Clostridium. In addition to ethanol, Clostridium bacteria may produce significant amounts of acetic acid (or acetate, depending on the pH) in addition to ethanol, depending upon process conditions.

[0104] In one embodiment, the processing facility includes methane reforming, where the methane reforming is part of ammonia production. Ammonia production, which is well-known to those skilled in the art, can be conducted using a Haber-Bosch synthesis. In the Haber-Bosch process, which is known to those skilled in the art, hydrogen is combined with nitrogen to produce ammonia according to the following reaction.N2+ 3H22NH3(13)

[0105] Without being limiting, the reaction is often conducted under high temperatures (e.g., between about 300°C and about 550°C) and high pressures (e.g., about 15 MPa to about 30 MPa) with a catalyst (e.g., an iron or ruthenium-based catalyst). The source of nitrogen is typically air. For example, an air separator can be used to provide relatively pure nitrogen gas that is fed to the ammonia synthesis with the hydrogen product. Alternatively, air can be used in the reforming (e.g., in a secondary reformer) such that the syngas produced from the reforming contains nitrogen in addition to carbon monoxide and hydrogen, and such that following WGS and carbon dioxide removal, a gas mixture that is predominately nitrogen and hydrogen can be fed to the ammonia synthesis.

[0106] In embodiments where the processing facility includes a biogas upgrading system and / or methane reforming followed by hydrogen purification, it can be advantageous when carbon dioxide derived from the biogas is provided for beneficial use.Beneficial Use of Carbon Dioxide

[0107] In one embodiment, the processing facility is adapted to capture carbon dioxide, where at least some of the captured carbon dioxide is derived from the biogas and is provided for beneficial use. In general, carbon dioxide derived from the biogas can be obtained from the biogas directly (e.g., can be captured directly from the biogas) or indirectly (e.g., can be captured from an off-gas produced from biogas upgrading, and / or can be captured from syngas produced by subjecting the biogas to methane reforming).

[0108] In one embodiment, the processing facility provides biogas upgrading and produces both biomethane and a carbon dioxide-rich stream (i.e., material having a carbon dioxide content of at least about 35%), where at least some of the carbon dioxide from the carbondioxide-rich stream is provided for beneficial use. In this embodiment, the carbon dioxiderich stream can be produced as part of biogas upgrading, or can be produced by subjecting an off-gas produced from biogas upgrading to one or more purifications. For example, the carbon dioxide-rich stream can be obtained from the regeneration of an adsorption or absorption material used in the biogas upgrading, or can be permeate produced by subjecting the biogas to a membrane separation, where the membrane is selectively permeable to carbon dioxide over methane.

[0109] As will be appreciated by those skilled in the art, it is often advantageous for carbon dioxide provided for beneficial use to be relatively pure (e.g., to be a carbon-dioxide rich stream having a carbon dioxide content of at least about 80%, preferably at least about 90%, and more preferably at least about 95%). As will be appreciated by those skilled in the art, such carbon dioxide can be provided in gaseous, liquid, supercritical, and / or a solid forms (e.g., depending on the purity).

[0110] The term “beneficial use,” as used herein with respect to a material (e.g., carbon dioxide), refers to the recycling and / or use of the material in lieu of disposal (e.g., in lieu of simply emitting the carbon dioxide to the atmosphere). The term “beneficial use,” as used herein, encompasses both direct use (e.g., where the carbon dioxide is not chemically altered) and conversion (e.g., where the carbon dioxide is converted to another material, such as building materials, fuels, or chemicals).[0011 l]Some non-limiting examples of beneficial use of carbon dioxide include: promoting plant growth in greenhouses; enhancing yields of biological processes; aquacultural projects (e.g., algae farms); enhanced oil recovery (EOR); fertilizer production (e.g., urea manufacturing); food and beverage production (e.g., carbonated beverages); dry cleaning, welding; fire suppression (e.g., in fire extinguishers); cooling (e.g., as a refrigerant); production of building material (e.g., aggregates, cement, concrete, etc.); fuel and / or chemical production (e.g., methane, methanol, gasoline / diesel / aviation fuel, polymers); and / or greenhouse gas reduction processes. For example, carbon dioxide can be provided to a greenhouse gas reduction process, where it is sequestered in a saline aquifer, depleted oil and gas field, or unmineable coal seam, and used to reduce the carbon intensity of the fuel produced (e.g., biomethane).

[0112] In one embodiment, the beneficial use includes enhanced oil recovery (EOR), where high-pressure carbon dioxide is injected into wells to carry more oil to the surface.

[0113] In one embodiment, the beneficial use includes fuel and / or chemical production (e.g., methane, methanol, formic acid, ethylene, etc.). In one embodiment, the fuel and / or chemical production includes combining carbon dioxide derived from the biogas with hydrogen (e.g., green hydrogen produced from the electrolysis of water).

[0114] In one embodiment, the beneficial use includes methanol production. For example, methanol can be produced from the direct hydrogenation of carbon dioxide, according to the following reaction:CO2+ 3H2CH3OH + H2O (14)

[0115] Without being limiting, such processes can be conducted with a catalyst (e.g., Cu / ZnO / AhCh), at elevated temperatures (e.g., between about 210°C and about 370°C) and pressures (e.g., between about 5 MPa and about 10 MPa).

[0116] Alternatively, methanol can be produced according to a two-step process, including a first step where carbon dioxide is converted to carbon monoxide via the reverse water gas shift (RWGS) reaction:CO2+ H2CO + H2O (15)

[0117] The resulting carbon monoxide syngas can then be converted to methanol according to Eq. 7. The production of carbon monoxide via the RWGS reaction is known to those skilled in the art. While the RWGS reaction can proceed at high temperatures without the use of a catalyst (e.g., between about 1000°C to about 1500°C), it can also be conducted at relatively low temperatures with a hydrogenation catalyst (e.g., between about 300°C to about 900°C).

[0118] In one embodiment, the beneficial use includes methane production. For example, methane can be produced from carbon dioxide according to the Sabatier reaction:CO2+ 4H2CH4+ 2H2O (16)

[0119] Without being limiting, this reaction can be conducted with a nickel catalyst, at elevated temperatures (e.g., between about 300°C and about 400°C) and pressures (e.g., between about 3 MPa). The methane resulting from this methanation reaction is often referred to as synthetic natural gas. Advantageously, this embodiment can produce additional methane, which is at least partially renewable, and which can be stored in a natural gas distribution system (e.g., optionally with the biomethane).

[0120] In embodiments where the beneficial use includes reacting the carbon dioxide derived from the biogas with hydrogen produced from the electrolysis of water (e.g., to produce methanol or synthetic natural gas), the process utilizes power-to-gas and / or power-to-fuel technology. Advantageously, the product(s) of this power-to-gas conversion (e.g., methanol and / or synthetic natural gas) can complement the off-peak energy storage associated with the production of the fuel (e.g., biomethane). Accordingly, in such embodiments, the carbon dioxide from the biogas and the methane from the biogas can both contribute to off-peak energy storage, without having to convert the biogas to electricity.

[0121] In one embodiment, the beneficial use includes at least one greenhouse gas reduction process.

[0122] The term “greenhouse gas reduction process,” as used herein, refers to any process conducted such that there is a reduction in greenhouse gases in the atmosphere relative to if the process was not conducted. In general, the greenhouse gas reduction process(es) referred to herein will include the sequestration and / or beneficial use of carbon dioxide.

[0123] In one embodiment, the greenhouse gas reduction process includes the sequestration of carbon dioxide. The term “sequestration”, as used herein with reference to carbon dioxide, refers to long-term storage of the carbon dioxide (e.g., substantially permanent geological storage, or storage in a product such as concrete). As will be understood by those skilled in the art, geological storage of carbon dioxide may require monitoring carbon dioxide leakage.

[0124] In one embodiment, the greenhouse gas reduction process includes the beneficial use of carbon dioxide. For example, in some cases, using carbon dioxide derived from the biogas can displace the use of fossil-based carbon dioxide (e.g., in an application where fossil-derived carbon dioxide is extracted or produced for the primary purpose of serving such application), and thus can reduce greenhouse gas emissions by avoiding the extraction or production of fossil-based carbon dioxide. In some cases, using carbon dioxide derived from the biogas, which is biogenic carbon dioxide, to produce one or more fuels (e.g., methane, methanol, gasoline, diesel, aviation fuel, etc.), can reduce greenhouse gas emissions by reducing the amount of fossil fuel that otherwise would have been extracted for producing the fuels.

[0125] As will be appreciated by those skilled in the art, feeding carbon dioxide derived from the biogas to one or more greenhouse gas reduction processes can reduce the carbon intensity of the fuel produced (e.g., biomethane).

[0126] The term “carbon intensity,” as used herein, refers to the quantity of life cycle greenhouse gas emissions associated with a product (e.g., fuel) for a given production process and is often expressed in grams of CO2 equivalent emissions per unit of product produced (e.g., gCChe / MJ of fuel, gCO2e / MMBTU of fuel, gCChe / kWh of electricity, or kgCChe / kg of fuel / product).

[0127] In general, life cycle greenhouse gas (GHG) emissions of a product can be determined from a Life Cycle Analysis (LCA). Life Cycle Analyses (LCAs) identify and estimate all “GHG emissions” and “GHG removals” in producing a product, from the growing or extraction of raw materials, to the production of the product, through to the end use (e.g., well-to-wheel). The term “greenhouse gas removal” or “GHG removal”, as used herein, refers to a negative GHG emissions contribution to the life cycle GHG emissions. For example, greenhouse gas removals can occur when carbon dioxide is sequestered and / or when biogenic carbon dioxide displaces the use of fossil carbon dioxide. In general, LCA assessments can be aided by software (e.g., GREET ®, SimaPro®, or GaBi).

[0128] As will be appreciated by those skilled in the art, life cycle GHG emissions and / or carbon intensity of product can be dependent upon the LCA methodology used, and when one or more credits for the product or its production are dependent on the life cycle GHG emissions, the LCA methodology will be selected to comply with the prevailing rules and regulations in the applicable jurisdiction (e.g., relevant to desired credits).

[0129] Various embodiments described herein provide various advantages.

[0130] 0ne advantage is that less biogas is wasted. For example, flares are often used at biogas power plants to reduce methane emissions to the atmosphere (e.g., during start up or downtime of the biogas power production, or when biogas production exceeds the capacity of the biogas power plant and / or storage). Unfortunately, flaring the excess biogas is a waste ofrenewable resources. However, in various embodiments described herein, at least some of the excess biogas can be diverted to mobile storage compression, and thus is not wasted.

[0131] Another advantage is that various embodiments can provide increased profits for biogas producers and / or biogas power producers. In general, the amount of electricity that a biogas power plant produces, and thus its profits, can be dependent on:1) the amount and quality of the biogas available (e.g., methane content);2) the installed capacity (e.g., nameplate capacity rating of the generator set(s));3) the electrical efficiency (e.g., often about 35% on a HHV basis);4) the operating time (e.g., the biogas power plant can be shut down for maintenance, repairs, and / or disruptions in biogas supply); and / or5) the load factor (e.g., the biogas power plant can be run below capacity if there is a limited supply of biogas and / or if one or more of the generator sets require maintenance).

[0132] In addition, the profits of a biogas power plant can be dependent on the price of electricity, which can be quite low during certain time periods (e.g., due to excess electricity produced from wind and / or solar being introduced into the power grid). Accordingly, it can be quite challenging for older biogas power plants to be economically viable (e.g., past their renumeration period). However, in various embodiments of the instant disclosure, profits can be maintained, or even increased, regardless of many of these factors. For example, since the profits are not solely linked to biogas power production, a low load factor, a shut down, and / or maintenance of the biogas power plant will not necessarily be associated with loss of revenue. Rather, the biogas diverted to mobile storage compression can be converted to more valuable fuel (e.g., biomethane). Advantageously, these increased profits can be achieved without requiring significant additional investments (e.g., to flexibilize the biogas power plant and / or provide biogas upgrading), and while increasing the return on previous investments (e.g., the biogas power plant does not need to be decommissioned, but rather can still provide revenue).

[0133] At least some of the increased profits result because various embodiments allow the best economic use of biogas on a dynamic basis. For example, since the biogas is dynamically directed between biogas power production and mobile storage compression(e.g., on demand), the biogas can be predominately directed to the end use that has the highest profits at that moment (e.g., biogas power production can be backed out during times of low electricity pricing and / or fed predominately to biogas power production only during times of the highest electricity pricing). In one embodiment, the gas is predominately (e.g., more than 50% of the biogas) fed to biogas power production when the price of electricity is above the 70th, 75th, 80th, or 85thpercentile of electricity prices from the past three months. In one embodiment, the gas is predominately (e.g., more than 50% of the biogas) fed to biogas power production for less than about 4, 3, or 2 hours per day.

[0134] Yet another advantage is that various embodiments can provide increased profits for the processing facility (e.g., biogas upgrader and / or fuel producer). For example, since the processing facility (e.g., that produces biomethane or another fuel) receives biogas from multiple biogas plants and / or biogas power plants, the load to the processing facility can be averaged using system storage, and downtime in the processing facility can be lower.Moreover, it facilitates the production of fuel, such as biogas upgrading, that can benefit from the economies of scale and / or is more efficient.

[0135] Yet another advantage is that various embodiments can benefit the power grid operator. In particular, various embodiments provide a system that is more adaptable for the needs of the power grid. For example, since the biogas can be provided to biogas power production on demand, electricity can be provided as needed (e.g., to balance supply and demand during peak times). In addition to providing flexible power generation, various embodiments also provide improved storage, increased demand response, and / or higher efficiency than would be have been achieved if the biogas power plant had been flexibilized (e.g., if the storage was added and the installed capacity doubled). For example, since the biogas is diverted to mobile storage compression instead of flexibilized storage, the biogas can be transported to the processing facility to produce biomethane. This biomethane can be stored more cost effectively and in larger amounts than the biogas of a flexibilized biogas power plant (e.g., can be stored in a natural gas distribution system) and thus can produce more electricity at peak times. Advantageously, when the biomethane is stored in a natural gas distribution system (e.g., is introduced into a natural gas distribution system having interconnected storage), gas derived from the biomethane can be withdrawn and converted toelectricity with greater efficiency. For example, while biogas power plants often have a low efficiency (e.g., about 35% on a HHV basis), natural gas power plants often have a relatively high efficiency (e.g., about 45% on a HHV basis).

[0136] A surprising advantage is that when the biogas diverted to mobile storage compression is converted to biomethane or hydrogen (e.g., at the processing facility), various embodiments can provide more off-peak storage (e.g., more hydrogen) per unit of energy in and / or provide off-peak storage having a relatively low carbon intensity (e.g., relative to if the biogas was converted to electricity, which was converted to hydrogen via electrolysis). For example, see the following Examples, which are provided to highlight some of the advantages and features of various embodiments, and in no way limit the various embodiments of the disclosure.Examples

[0137] Fig. 3 shows three scenarios (A, B, and C), for which the amount of hydrogen that can be produced has been calculated.

[0138] Scenario A corresponds to a first comparative example, wherein wind 100 is converted to a quantity of renewable electricity 101, which is converted to a quantity of hydrogen via electrolysis 102. The efficiency of the conversion is assumed to be 70% for the purposes of this example. Accordingly, if the first amount is normalized as one unit, the amount of hydrogen produced is 0.7 units.

[0139] Scenario B corresponds to a second comparative example, wherein a quantity of biogas 200 is converted to one unit of renewable electricity 201, which is converted to hydrogen via electrolysis 202. The power production 201 is assumed to combust raw biogas with a 1 MW internal combustion engine having an efficiency of 35% on a HHV basis. The efficiency of the electrolysis is assumed to be 70%, such that the amount of hydrogen produced is 0.7 units.

[0140] Scenario C corresponds to an example according to one embodiment, wherein a quantity of biogas 200 is upgraded to biomethane 300 (e.g., at a processing facility following transport). The gas derived from the biomethane, which can be withdrawn from a natural gasdistribution system, is then converted to renewable electricity 301, which is converted to hydrogen via electrolysis 302. The methane recovery from biomethane production is assumed to be 90%. The power production 301 is assumed to combust biomethane and have an efficiency of 45% on a HHV basis. The efficiency of the electrolysis is assumed to be 70%. Since the power production 301 has a higher efficiency than the biogas power production 201, more electricity, and thus more hydrogen, can be produced from the same amount of biogas (e.g., the amount of hydrogen that can be produced was calculated to be 0.9 units).

[0141] As illustrated via the examples, various embodiments of the disclosure can facilitate feeding some of the biogas directly to power production (e.g., during peak times), thereby increasing the return on previous investments and exploiting the dispatchable nature of the biogas, and diverting some of the biogas to mobile storage compression (e.g., during off-peak times), which can be converted to biomethane and used to produce a relatively high amount of electricity and hydrogen (e.g., during peak times). Accordingly, more off-peak energy storage can be provided for the biogas provided.

[0142] Referring to Fig. 4, there is shown a scenario where the biomethane 300 is used to produce hydrogen 402 via steam methane reforming (SMR) 401, rather than through electrolysis. Assuming that the SMR has an overall efficiency of 85% on an HHV basis, this scenario produces 1.5 units of hydrogen (e.g., is not limited by the low efficiency of electrolysis).

[0143] As a result of producing more hydrogen and / or as a result of providing carbon dioxide derived from the biogas for beneficial use (e.g., a greenhouse gas reduction process), the scenario in Fig. 4 can have a relatively low carbon dioxide footprint. For example, the carbon dioxide can be captured as part of biogas upgrading and / or from hydrogen production (e.g., from the syngas produced from steam methane reforming), each of which can be economically advantageous relative to capturing carbon dioxide from flue gas produced from combusting biogas for power production.

[0144] Advantageously, various embodiments of the present disclosure can provide a solution to the economic challenges associated with biogas power production arising fromlow or negative electricity prices, which can be widely adopted. For example, in some embodiments, wherein there is a centralized processing facility, the operators of the processing facility can seek out and / or identify various biogas power plants that are connected to relatively small biogas plants, and arrange to have their biogas delivered to the centralized processing facility. Including more biogas power plants within various embodiments of the disclosure can facilitate more renewable electricity derived from biogas being used to manage the supply and demand of the power grid, and thus increase the renewable share of energy for the grid.

[0145] Further advantageously, various embodiments of the present disclosure can provide a solution for landfills having waning productions. The production of biogas from landfills typically ebbs with time. If the production of landfill gas wanes to a point that it is no longer economical to operate an associated biogas power plant in baseload mode, then various embodiments described herein can offer a profitable solution.

[0146] The terminology used herein is for the purpose of describing certain embodiments only and is not intended to be limiting of the invention. For example, as used herein, the singular forms "a," "an," and "the" may include plural references unless the context clearly dictates otherwise. The terms “comprises”, "comprising", “including”, and / or “includes”, as used herein, are intended to mean "including but not limited to." The term “and / or”, as used herein, is intended to refer to either or both of the elements so conjoined. In the context of describing the combining of components by the “addition” or “adding” of one component to another, or the separating of components by the “removal” or “removing” of one component from another, those skilled in the art will understand that the order of addition / removal is not critical (unless stated otherwise). The terms “remove”, “removing”, and “removal”, with reference to one or more impurities, contaminants, and / or constituents of biogas, includes partial removal. The terms “cause” or “causing”, as used herein, may include arranging or bringing about a specific result (e.g., a withdrawal of a gas), either directly or indirectly, or to play a role in a series of activities (e.g., through commercial arrangements such as a written agreement, verbal agreement, or contract). The term “providing” as used herein with respect to something, refers to directly or indirectly obtaining the thing and / or making the thingavailable for use. Unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art.

[0001] 0f course, the above embodiments have been provided as examples only. It will be appreciated by those of ordinary skill in the art that various modifications, alternate configurations, and / or equivalents will be employed without departing from the scope of the invention. Accordingly, the scope of the invention is therefore intended to be limited solely by the scope of the appended claims.

Claims

Claims1. A method of providing off-peak energy storage, the method comprising:providing mobile storage for collecting biogas produced from one or more biogas plants, each of the one or more biogas plants connected to a biogas power plant having at least one electric generator for producing electricity from biogas, at least some of the electricity fed into a power grid;diverting, or arranging for the diversion of, the biogas away from at least one of the electric generators and to mobile storage compression during one or more off-peak times, thereby reducing an amount of electricity fed into the power grid during the one or more off-peak times, wherein biogas compressed by the mobile storage compression is fed into the mobile storage;delivering the compressed biogas in the mobile storage to a processing facility that: (i) processes at least some of the delivered biogas, the processing comprising capturing carbon dioxide and producing biomethane, (ii) provides at least some of the biomethane to a natural gas distribution system having interconnected storage, and (iii) provides at least some of the captured carbon dioxide for beneficial use.

2. The method according to claim 1, wherein gas derived from the biomethane is withdrawn from the natural gas distribution system for power production during one or more peak times.

3. The method according to claim 1, wherein gas derived from the biomethane is withdrawn from the natural gas distribution system for fuel production.

4. The method according to claim 3, wherein the fuel production comprises hydrogen production, methanol production, ammonia production, or any combination thereof.

5. The method according to any one of claims 1 to 4, wherein the beneficial use comprises at least one greenhouse gas reduction process.

6. The method according to claim 5, wherein the at least one greenhouse gas reduction process comprises geological sequestration, enhanced oil recovery (EOR), or a combination thereof.

7. The method according to any one of claims 1 to 5, wherein the beneficial use comprises producing one or more fuels, chemicals, or combination thereof.

8. The method according to claim 7, wherein the one or more fuels, chemicals, or combination thereof comprise synthetic natural gas, methanol, or a combination thereof.

9. The method according to claim 7, wherein the beneficial use comprises subjecting at least some of the captured carbon dioxide to a reaction with hydrogen, wherein the hydrogen is produced from electrolysis.

10. The method according to any one of claims 1 to 8, wherein (iii) comprises introducing at least some of the captured carbon dioxide into a carbon dioxide distribution system.

11. The method according to any one of claims 1 to 10, wherein the biogas is subjected to partial purification prior to being diverted away from at least one of the electric generators.

12. The method according to claim 11, wherein the partial purification comprises removing hydrogen sulfide.

13. The method according to claim 11 or 12, wherein the partial purification comprises removing carbon dioxide.

14. The method according to any one of claims 1 to 12, wherein electricity produced from at least one of the biogas power plants is used for the mobile storage compression.

15. The method according to any one of claims 1 to 14, wherein mobile storage compression compresses at least some of the biogas to at least 1500 psig for transport in the mobile storage, and wherein cold temperatures resulting from the decompression of the mobile storage are used for processing of the delivered biogas.

16. The method according to any of claims 1 to 15, wherein one or more of the electric generators are generator sets.

17. A method of providing off-peak energy storage, the method comprising:collecting biogas produced from at least one biogas plant, the at least one biogas plant connected to a biogas power plant, the biogas power plant having at least one electric generator for converting at least some of the biogas to electricity and adapted to feed the electricity into a power grid;at one or more peak times, feeding at least some of the collected biogas to the biogas power plant and operating the biogas power plant at or near capacity;at one or more off-peak times, diverting at least some of the collected biogas away from at least one of the electric generators and to mobile storage compression, thereby reducing an amount of electricity fed into the power grid during off-peak times;compressing the diverted biogas and feeding the compressed gas to mobile storage;providing the mobile storage containing the compressed biogas for transport to a processing facility that: (i) processes at least some of the biogas transported in the mobile storage, the processing comprising capturing carbon dioxide and producing biomethane, (ii) provides at least some of the biomethane to a natural gas distribution system having interconnected storage, and (iii) provides at least some of the captured carbon dioxide for beneficial use.

18. A method of providing off-peak energy storage, the method comprising:collecting biogas produced from at least one biogas plant, the at least one biogas plant connected to a biogas power plant, the biogas power plant having at least one electric generator for converting at least some of the biogas to electricity and adapted to feed the electricity into a power grid;at one or more peak times, feeding at least some of the collected biogas to the biogas power plant and operating the biogas power plant at or near capacity;at one or more off-peak times, diverting at least some of the collected biogas away from at least one of the electric generators and to mobile storage compression, thereby reducing an amount of electricity fed into the power grid during off-peak times;compressing the diverted biogas and feeding the compressed gas to mobile storage;providing the mobile storage containing the compressed biogas for transport to a processing facility that: (i) processes at least some of the biogas transported in the mobile storage to produce fuel, the processing comprising capturing carbon dioxide; (ii) stores the fuel; and (iii) provides at least some of the captured carbon dioxide for beneficial use.

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