A mobile off-grid photovoltaic and elevated tank flexible energy storage device and method

Abstract

This invention discloses a mobile off-grid photovoltaic and elevated tank flexible energy storage device and method, relating to the field of energy supply technology. It includes an off-grid photovoltaic power generation system utilizing solar energy; a mobile elevated tank for storing and transporting well-produced fluids or storage media; a first electric heating rod for heating the well-produced fluids or media; a second electric heating rod, powered by grid electricity as a backup heating device, also used for heating the well-produced fluids or media; and a controller for controlling the opening and closing of the first and second electric heating rods. By directly connecting the photovoltaic system to the low-voltage power distribution system of the elevated tank, direct conversion of solar energy into electrical energy is achieved, enabling efficient utilization of clean energy in areas without a power grid or with an unstable grid. The operation of the photovoltaic system and the crude oil energy storage system is dynamically adjusted according to sunlight conditions and heat demand to ensure a stable energy supply.

Description

Technical Field

[0001] This invention relates to the field of energy supply technology, specifically to a mobile off-grid photovoltaic and elevated tank flexible energy storage device and method. Background Technology

[0002] In remote areas of oil and gas fields, transportation areas, and regions with unstable or scarce energy supplies, elevated tanks are often used to store crude oil and other media. To ensure that the pour point and transportation temperature of these media meet the requirements, elevated tanks require temperature maintenance and heating operations.

[0003] Currently, the maintenance and heating of elevated tanks mainly employ either flame-fired tanks or electric heating technology. Flame-fired tanks achieve maintenance and heating by converting natural gas into heat energy, but this method is limited by high natural gas consumption, low combustion efficiency, and the need for a sufficient natural gas supply. Furthermore, with increasingly stringent environmental protection requirements, flame-fired tanks are gradually being phased out.

[0004] Electric heating directly converts electrical energy into heat energy. As a direct and efficient heating method, it has been widely used in elevated tanks, as shown in Chinese utility model patent publication number CN211008572U. Electric heating equipment typically uses components such as resistance wires and heating tubes to convert electrical energy into heat energy to heat the medium inside the elevated tank. Although electric heating equipment is constantly advancing in technology, its energy efficiency improvement potential is relatively limited due to the limitations of physical principles and the performance of existing materials. At the same time, thermal power generation (i.e., traditional fossil fuel power generation) still accounts for a relatively high proportion of current electricity generation, while the proportion of clean energy is relatively low, which limits the potential for reducing carbon emissions.

[0005] On the other hand, while new energy sources such as solar and wind power are clean and renewable, their internal rate of return (IRR) for replacing traditional fossil fuel power in electric heating is not ideal in practical applications due to limitations in technological maturity, cost, and stability. Therefore, current electric heating systems often still rely on traditional fossil fuel power, making it difficult to effectively reduce carbon emissions. Summary of the Invention

[0006] The purpose of this invention is to provide a mobile off-grid photovoltaic and elevated tank flexible energy storage device and method, which realizes the complementary utilization of renewable energy (solar energy) and traditional energy (crude oil), improves thermal storage efficiency and clean energy utilization rate, and reduces energy consumption and carbon emissions.

[0007] To achieve the above objectives, the technical solution of this application is: a mobile off-grid photovoltaic and elevated tank flexible energy storage device, comprising:

[0008] Off-grid photovoltaic power generation systems utilize solar energy to generate electricity;

[0009] Mobile elevated tanks are used to store and transport well site produced fluids or storage media.

[0010] The first electric heating rod is connected to the off-grid photovoltaic power generation system and the mobile elevated tank, respectively, and is used to heat the produced fluid or medium at the well site;

[0011] The second electric heating rod, powered by grid electricity as a backup heating device, is connected to the mobile elevated tank and is used to heat the produced fluid or medium at the well site.

[0012] The controller is connected to the first and second electric heating rods respectively, and is used to control their on or off.

[0013] In one embodiment, the off-grid photovoltaic power generation system and / or the mobile elevated tank is mounted on a mobile skid.

[0014] In one embodiment, the second electric heating rod is provided with a reserved interface for connecting to a wind power system.

[0015] In one embodiment, the well site produced fluid or medium is transported to a mobile elevated tank via an unheated gathering and transportation pipeline.

[0016] In one embodiment, if the well site produced fluid or medium in the mobile elevated tank does not reach the required temperature when the first electric heating rod heats it, the well site produced fluid or medium in the mobile elevated tank is then heated by a second electric heating rod until the required temperature is reached.

[0017] This invention also provides a method for mobile off-grid photovoltaic and elevated tank flexible energy storage, comprising:

[0018] When there is sufficient sunlight, the off-grid photovoltaic power generation system provides power to the first electric heating rod, which heats the well site produced fluid or medium in the mobile elevated tank.

[0019] During periods of insufficient or no light, the second electric heating rod is powered by grid electricity, and the second electric heating rod heats the well site produced fluid or medium in the mobile elevated tank.

[0020] In one embodiment, when the off-grid photovoltaic power generation system generates sufficient power, the mobile elevated tank is first heated to the required temperature. Once the temperature is reached, the excess heat energy is carried to the downstream process through the well site produced fluid or medium.

[0021] In one embodiment, the mobile elevated tank is heated to a first temperature using off-peak electricity during morning transport shifts.

[0022] In one embodiment, if the first temperature does not reach the desired temperature, then electric heating is used.

[0023] In one embodiment, during the afternoon transport shift of the mobile elevated tank, an off-grid photovoltaic power generation system is first used to provide power to the first electric heating rod, which is then used to heat or maintain the temperature of the mobile elevated tank.

[0024] This invention, by employing the above technical solutions, achieves the following technical effects: This invention proposes a technology combining a flexible heat load in an elevated tank with an off-grid photovoltaic power generation system. This technology directly connects a single photovoltaic power generation system to the low-voltage power distribution system of a single electric heating rod, enabling direct power supply from photovoltaic green electricity for the heating process. This technology deeply explores the heat storage potential of the well site produced fluid or medium in the elevated tank, ensuring that the heat load matches the characteristics of photovoltaic power generation. When photovoltaic power generation is sufficient, excess heat can be transferred to downstream processes such as the dehydration unit, thereby further reducing the energy consumption of the dehydration system. When photovoltaic power generation is insufficient, it can automatically switch to backup grid power supply to ensure continuous operation. Furthermore, this technology ensures complete self-consumption of photovoltaic power generation, has low construction costs, and an expected internal rate of return of up to 9%.

[0025] By using a mobile skid, this technology can flexibly adapt to dynamic changes in oilfield block production capacity. It can be adjusted according to production demand, achieving the benefit of a one-time investment with multiple uses, effectively reducing the cost of reinvestment.

[0026] This technology is particularly effective in remote areas, addressing the challenges of poor conditions and high investment costs for new pipelines and power lines. It provides a technically feasible and economically efficient carbon reduction production solution. A single system can save 25,000 kWh of grid electricity, reduce carbon emissions by 6.2 tons, and increase the proportion of green electricity by 14%. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 A schematic diagram of the principle framework of a mobile off-grid photovoltaic and elevated tank flexible energy storage device;

[0029] Figure 2 This is a schematic diagram illustrating the principle framework of a mobile off-grid photovoltaic system combined with a flexible energy storage method using elevated tanks. Detailed Implementation

[0030] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0031] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0032] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise expressly specified. "Several" means one or more, unless otherwise expressly specified.

[0033] In the description of this application, it should be understood that the terms "center", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0034] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0035] Traditional energy supply methods often face high construction and operating costs, especially in remote areas. Mobile off-grid photovoltaic (PV) systems combined with elevated tank energy storage devices reduce energy supply costs by utilizing solar energy, a free resource. Simultaneously, through proper design and optimization, energy efficiency can be improved, energy waste reduced, and a balance between cost and benefit achieved. This overcomes the limitations of conventional solar energy utilization in terms of technology, cost, and grid connection fluctuations, enabling a highly efficient combination of off-grid PV and electric heating energy storage, and promoting the replacement of traditional fossil fuel power with clean energy.

[0036] Example 1

[0037] Please see Figure 1 Single energy supply methods often have shortcomings and are difficult to cope with various complex situations and changes in demand. This embodiment provides a mobile off-grid photovoltaic and elevated tank flexible energy storage device, including:

[0038] This off-grid photovoltaic (PV) power generation system integrates PV modules and connects them independently to the low-voltage power distribution system of an elevated tank (the first electric heating rod), achieving energy self-sufficiency in areas without grid coverage or with unstable grids. The PV system directly converts solar energy into electricity, providing a stable power supply to remote areas or special application scenarios, solving the problems of traditional grid coverage or unstable power supply. Due to its off-grid design, this system effectively complements the external power grid, enhancing its ability to operate independently under various climatic and geographical conditions, and strengthening the reliability and resilience of energy supply.

[0039] Mobile elevated tanks are used to store and transport produced fluids or storage media from well sites. They fully utilize the potential for temperature rise in the produced fluids and media, ensuring the heat load matches the characteristics of photovoltaic power generation. By using elevated tanks as energy storage devices, safety issues during the storage and transportation of produced fluids and media are effectively resolved. Elevated tanks reduce the risk of ground contamination, facilitate management and maintenance, improve the storage efficiency and stability of produced fluids and media, and reduce energy loss and waste.

[0040] The first electric heating rod is connected to the off-grid photovoltaic power generation system and the mobile elevated tank, respectively, and is used to heat the produced fluid or medium at the well site; when the photovoltaic power generation is sufficient, the first electric heating rod is used for heating; the photovoltaic power generation is fully self-consumed.

[0041] The second electric heating rod, powered by grid electricity as a backup heating device, is connected to the mobile elevated tank and is used to heat the produced fluid or medium at the well site. When photovoltaic power generation is insufficient or the required temperature is not reached, this second electric heating rod is used for heating to ensure the stable operation of the elevated tank.

[0042] The controller is connected to the first and second electric heating rods respectively, and is used to control their on or off.

[0043] As a preferred embodiment provided in this example, the off-grid photovoltaic power generation system and / or the mobile elevated tank is mounted on a mobile skid. The mobile design allows the technology to be flexibly deployed to locations requiring energy supply, whether in remote areas, emergency rescue sites, or temporary facilities, providing rapid power and energy support.

[0044] In one embodiment, the second electric heating rod is provided with a reserved interface for connecting to a wind power system. When there is sufficient wind power in the area, it can be connected to a wind power system to meet the green electricity supply during periods of no sunlight, further improving the clean energy utilization rate of the system and realizing the utilization of clean energy at all times.

[0045] Crude oil produced at well sites is an important energy resource, but its storage and transportation pose safety risks. Traditional surface storage tanks are susceptible to natural disasters, human sabotage, or environmental pollution, leading to crude oil leaks and contamination. Elevated tank designs, by raising the tanks, reduce the risk of ground contamination, while also facilitating management and maintenance, thus improving the safety of crude oil storage. This addresses the problems of high construction costs and insufficient economic returns in the early stages of oil and gas field production. Mobile elevated tanks are adaptable to crude oil development and production, and can be moved to other areas where they are needed later for recycling.

[0046] The organic combination of photovoltaics and mobile elevated tanks in this invention can improve thermal storage efficiency, increase clean energy utilization, and reduce energy consumption and carbon emissions. The entire system aligns with the green and low-carbon development trend and helps promote the transformation and upgrading of the energy structure. This system achieves efficient and cyclical energy utilization, conforming to the concept of sustainable development.

[0047] Example 2

[0048] Please see Figure 2 This embodiment provides a mobile off-grid photovoltaic and elevated tank flexible energy storage method, which ensures energy security while meeting environmental protection requirements and promotes the transformation of oil and gas field production towards a green and low-carbon direction. It is particularly suitable for remote areas, transportation areas, and areas with unstable or scarce energy supplies. The method includes:

[0049] When there is sufficient sunlight, the off-grid photovoltaic power generation system provides power to the first electric heating rod, which heats the well site produced fluid or medium in the mobile elevated tank. When the off-grid photovoltaic power generation system generates sufficient power, it first ensures that the mobile elevated tank is heated to the required temperature. After reaching the required temperature, the excess heat energy is carried to the downstream process through the well site produced fluid or medium. As a representative of clean energy, photovoltaics does not produce pollutants or greenhouse gas emissions during its utilization, which helps to reduce environmental pollution and address climate change.

[0050] During periods of insufficient or no light, the second electric heating rod is powered by grid electricity. This second electric heating rod heats the well site produced fluid or medium in the mobile elevated tank. Even without the second electric heating rod, the residual heat from the first electric heating rod can be used to maintain the temperature, ensuring that the medium does not solidify and that it reaches a certain transport temperature, thus guaranteeing the continuous and stable operation of the system.

[0051] As a preferred embodiment provided in this example, the mobile elevated tank is heated to a first temperature using off-peak electricity during the morning transport shift. If the first temperature does not reach the required temperature, it is heated using regular electricity. During the afternoon transport shift, the mobile elevated tank is first powered by an off-grid photovoltaic power generation system to provide power to the first electric heating rod, and then the mobile elevated tank is heated or maintained at a certain temperature through the first electric heating rod.

[0052] For example, a single photovoltaic system with a capacity of 18kWp is connected to the low-voltage power distribution system of one 18kW electric heating rod in the elevated tank, while the other 18kW electric heating rod uses grid power. The system fully utilizes photovoltaic green electricity for heating. During morning transport shifts, the elevated tank utilizes off-peak electricity (22:00-06:00 the next day) for 4 to 7 hours of heating, raising the temperature from 15℃ to a maximum of 47℃. In the heavy oil block, it utilizes regular electricity (06:00-08:00) for another 2 hours of heating, raising the temperature to 55℃. During afternoon transport shifts, the elevated tank utilizes photovoltaic green electricity for heating / temperature maintenance at midday. When the elevated tank is used for multi-day transport, it fully utilizes midday photovoltaic power generation and stores the heat energy in the storage medium of the elevated tank, achieving photovoltaic heating for both heating and temperature maintenance.

[0053] Off-grid photovoltaic power generation systems are highly efficient during the day when sunlight is abundant, while mobile elevated tanks can release stored heat at night or when sunlight is insufficient. This complementary energy characteristic enables the entire system to operate stably under all-weather conditions. Simultaneously, the mobile elevated tanks can release heat when needed to meet the thermal energy demands of downstream production.

[0054] The aforementioned technologies have been applied in 70 sets in the "Cicai Low-Carbon Production Construction Plan," which is expected to save 1.8 million kilowatt-hours of electricity annually, resulting in direct economic benefits of 930,000 yuan. It also has social benefits, reducing carbon emissions by 1,400 tons.

[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A mobile off-grid photovoltaic and elevated tank flexible energy storage device, characterized in that, include: Off-grid photovoltaic power generation systems utilize solar energy to generate electricity; Mobile elevated tanks are used to store and transport well site produced fluids or storage media. The first electric heating rod is connected to the off-grid photovoltaic power generation system and the mobile elevated tank, respectively, and is used to heat the produced fluid or medium at the well site; The second electric heating rod, powered by grid electricity as a backup heating device, is connected to the mobile elevated tank and is used to heat the produced fluid or medium at the well site. The controller is connected to the first and second electric heating rods respectively, and is used to control their on or off.

2. The mobile off-grid photovoltaic and elevated tank flexible energy storage device according to claim 1, characterized in that, The off-grid photovoltaic power generation system and / or mobile elevated tank are installed on a mobile skid.

3. The mobile off-grid photovoltaic and elevated tank flexible energy storage device according to claim 1, characterized in that, The second electric heating rod has a reserved interface for connecting to the wind power system.

4. The mobile off-grid photovoltaic and elevated tank flexible energy storage device according to claim 1, characterized in that, The well site produced fluid or medium is transported to a mobile elevated tank via an unheated gathering and transportation pipeline.

5. The mobile off-grid photovoltaic and elevated tank flexible energy storage device according to claim 1, characterized in that, If the first electric heating rod fails to reach the required temperature when heating the well site produced fluid or medium in the mobile elevated tank, a second electric heating rod is used to heat the well site produced fluid or medium in the mobile elevated tank until the required temperature is reached.

6. A method for mobile off-grid photovoltaic and elevated tank flexible energy storage, characterized in that, include: When there is sufficient sunlight, the off-grid photovoltaic power generation system provides power to the first electric heating rod, which heats the well site produced fluid or medium in the mobile elevated tank. During periods of insufficient or no light, the second electric heating rod is powered by grid electricity, and the second electric heating rod heats the well site produced fluid or medium in the mobile elevated tank.

7. The mobile off-grid photovoltaic and elevated tank flexible energy storage method according to claim 6, characterized in that, When the off-grid photovoltaic power generation system generates sufficient power, the mobile elevated tank is heated first. Once the required temperature is reached, the excess heat energy is carried to the downstream process through the well site produced fluid or medium.

8. The mobile off-grid photovoltaic and elevated tank flexible energy storage method according to claim 6, characterized in that, The mobile elevated tanks are heated to the first temperature using off-peak electricity during morning transport shifts.

9. The mobile off-grid photovoltaic and elevated tank flexible energy storage method according to claim 8, characterized in that, If the first temperature does not reach the required temperature, then use electric heating.

10. A mobile off-grid photovoltaic and elevated tank flexible energy storage method according to claim 6, characterized in that, The mobile elevated tank is transported in the afternoon. First, an off-grid photovoltaic power generation system is used to provide power to the first electric heating rod, and then the first electric heating rod is used to heat or maintain the temperature of the mobile elevated tank.

Images