Underground pumped storage system based on abandoned mine underground space reconstruction
By reconstructing concentric or array-structured underground reservoirs and backfilling them with soil and rock in abandoned mines, the spatial limitations and geological safety issues of traditional pumped storage systems have been resolved, achieving an efficient and economical underground energy storage solution.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-29
- Publication Date
- 2026-03-31
AI Technical Summary
Traditional pumped storage power stations are constrained by terrain conditions, have high land acquisition costs and significant ecological disturbances. The reconstruction scheme for underground space in abandoned mines has not yet met the large-scale energy storage needs, and the poor structural stability makes it difficult to meet the load-bearing and sealing requirements of large underground reservoirs.
By utilizing abandoned mine tunnels and goaf areas to reconstruct underground reservoirs, and by constructing new underground tunnels and modifying existing tunnels to form concentric circles or array structures, combined with soil and rock backfilling, high-density water storage and parallel construction of multiple work faces can be achieved, ensuring system safety and economy.
It significantly increases water storage capacity per unit area, shortens construction period, reduces project costs, eliminates geological safety hazards, and achieves economically feasible and efficient energy storage.
Smart Images
Figure CN121760784A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of power, and in particular relates to an underground pumped storage system based on the reconstruction of underground space in abandoned mines. Background Technology
[0002] Pumped storage, as the most mature and reliable long-term energy storage technology, plays an irreplaceable role in supporting the grid connection of high proportions of renewable energy. However, traditional pumped storage power stations rely on two surface reservoirs, which are significantly constrained by terrain conditions and face problems such as high land acquisition costs and significant ecological disturbance, thus limiting their resource development potential.
[0003] Against this backdrop, the construction of underground pumped storage systems has become an important direction for expanding the boundaries of energy resources. my country has accumulated rich technical reserves and engineering experience in excavating underground reservoirs and power plants in deep underground spaces. Although using tunnel boring machines to excavate long-distance tunnels from the surface to the ground still requires a large investment in infrastructure and incurs high costs, considering the entire life-cycle investment, including surface connection works, the cost per kilowatt-hour of underground pumped storage systems is basically equivalent to that of conventional surface pumped storage systems, demonstrating good economic feasibility and development prospects.
[0004] In addition, recent studies have proposed underground pumped-storage energy storage schemes based on abandoned mines, utilizing the tunnels and goaf areas of abandoned mines as underground reservoirs or power plants. However, such schemes are currently only at the design stage and have not yet entered actual construction. The main reasons are: the structural stability of goaf areas is poor, making it difficult to meet the load-bearing and sealing requirements of large underground reservoirs; while existing tunnels, although structurally relatively stable, have limited volume, making it difficult to support large-scale energy storage needs. Summary of the Invention
[0005] To address the aforementioned problems, this invention proposes an underground pumped-storage energy system based on the reconstruction of underground space in abandoned mines. This system uses existing roadways in abandoned mines as the starting working face, or modifies existing underground passages to construct new underground transportation channels, significantly reducing construction costs and time. Large excavating equipment and tunnel boring machine components can be transported underground for assembly via existing roadways or through channels modified from existing roadways. A new tunnel is then excavated in stable rock strata to form a dedicated underground reservoir. Notably, the new reservoir site avoids unstable strata to ensure long-term operational safety.
[0006] Meanwhile, the soil and rock generated during the excavation process do not need to be transported to the surface, but are directly backfilled into the adjacent abandoned mining area. This not only significantly reduces the cost of transporting soil and rock, but also achieves effective filling and reinforcement of the mining area, effectively preventing geological disasters such as water seepage, and improving the safety and environmental friendliness of the entire system.
[0007] In summary, this system, through the rational reconstruction of the underground space of abandoned mines, not only makes full use of idle industrial resources, turning waste into treasure, but also simultaneously completes the safety management and ecological restoration of abandoned mines. This innovative model deeply integrates abandoned industrial facilities with new energy storage technologies, providing a high-quality solution for new energy development that combines economy, safety, and sustainability. The specific technical solution is as follows:
[0008] An underground pumped storage system based on the reconstruction of underground space in abandoned mines includes:
[0009] The underground reservoir is constructed by building a new underground tunnel, which connects to the existing tunnels. The underground reservoir adopts a concentric circle structure or an array structure.
[0010] The soil and rock backfill structure will backfill all the soil and rock generated from the excavation of the new underground space into the mined-out area;
[0011] Above-ground reservoirs are reservoirs built on land or natural bodies of water on land, used to store water at high levels;
[0012] A water conveyance system is constructed using the vertical shafts of abandoned mines to connect the above-ground reservoir and the underground reservoir, thereby enabling the circulation of water between the upper and lower reservoirs.
[0013] Cable channels are constructed using the shafts of abandoned mines to connect underground transformers with above-ground switch stations and power grids, thereby connecting underground pumped storage units to the above-ground power grid.
[0014] An underground power plant will be built using newly constructed underground space to install water pumps, turbines, and electric generators.
[0015] Preferably, the concentric circle structure includes multiple concentrically arranged annular cavities. One end of the concentric circle structure is the starting point for the excavation of the underground reservoir. A plug is set to enclose the reservoir and maintain the water level of the underground reservoir. During the excavation of the outer large-diameter concentric circle, a new construction face is opened on the completed excavation surface. The excavation moves towards the inner ring and simultaneously opens the inner ring reservoir. The inner and outer ring reservoirs are excavated at the same time. During the construction of the inner and outer ring reservoirs, a new construction face is opened and different radial straight reservoirs are excavated. At different positions of the inner and outer ring reservoirs, the inner and outer rings are connected by radial straight reservoirs.
[0016] Preferably, the array structure includes multiple horizontal and vertical straight reservoirs. The connection points of the horizontal reservoirs converge into an entrance tunnel. A plug is installed at the entrance tunnel to ensure the water level of the reservoir. During the construction of the horizontal straight reservoirs, the entrance tunnel is split into multiple straight reservoirs for simultaneous construction. A new excavation plane is opened in the part where the straight tunnel excavation is completed, and the vertical straight reservoirs are extended and excavated.
[0017] Preferably, in the case of a newly constructed underground reservoir consisting of an underground space tunnel, a load-bearing sealing layer is installed between the underground reservoir and the surrounding rock.
[0018] Preferably, the existing roadways of the abandoned mine are used to form an underground powerhouse or the existing roadways are transformed into an underground powerhouse for the installation of electrical equipment.
[0019] Preferably, an inclined shaft can also be used.
[0020] Preferably, the system is installed in underground rock formations, which are covered by a soil layer.
[0021] Preferably, a goaf plug is constructed at one end of the goaf.
[0022] Preferably, the pump-turbine is a bidirectional operating device, which acts as a pump to draw water from the underground reservoir to the upper reservoir during periods of surplus electricity, and as a turbine to generate electricity during peak electricity demand periods, driving the generator to output electrical energy.
[0023] Preferably, the power equipment includes a transformer.
[0024] The present invention achieves the following beneficial effects:
[0025] 1. Achieve high-density water storage and overcome space limitations: By adopting a concentric circle structure or a multi-unit array structure, multiple annular or grid-like cavity units are densely arranged within a limited horizontal projection area, significantly improving the water storage capacity per unit area and effectively solving the problem of insufficient capacity of traditional single-cavity structures.
[0026] 2. Supports parallel construction of multiple work surfaces, greatly improving efficiency: The concentric circle structure divides the annular cavity into multiple independent fan-shaped areas through radial channels, while the array structure forms multiple closed cavity units through longitudinal and transverse channels. Each area or unit can be excavated simultaneously as an independent work surface, greatly shortening the construction cycle and reducing project costs.
[0027] 3. Eliminate geological safety hazards and ensure operational safety: All the soil and rock generated from the excavation of the new underground space will be backfilled into the original mining area, effectively filling the voids and compacting the loose rock layers, fundamentally eliminating the risk of geological disasters, while avoiding the environmental burden caused by transporting soil and rock out of the site.
[0028] 4. Enhance the overall economic efficiency and sustainability of the system: By using "excavation instead of filling" to achieve zero external transportation of soil and rock, transportation and disposal costs are saved; existing mine roadways are transformed into underground powerhouses, reducing the amount of new construction projects; and high-density water storage structures reduce the investment cost per kilowatt, making the project economically feasible and stable in the long term. Attached Figure Description
[0029] Figure 1 This is a schematic diagram of an underground pumped storage system based on the reconstruction of underground space in an abandoned mine, according to the present invention.
[0030] Among them: 101-soil layer, 102-rock layer, 103-vertical shaft, 103B-inclined shaft, 104-surface water source / upper reservoir, 105-newly excavated main horizontal shaft, 106-newly excavated sub-horizontal shaft, 107-excavation machinery, 108-plug, 109-water pipeline, 110-transformer, 111-water pump turbine, 112-mineral layer 1, 113-mineral layer 2, 114-roadway, 115-goaf, 116-newly excavated rock and soil backfill, 117-goaf plug, 118-water pipeline, 119-cable channel, 120-hoisting mechanism.
[0031] Figure 2 shows a concentric circle underground reservoir;
[0032] Figure 3 is a schematic diagram of an array-structured underground reservoir. Detailed Implementation
[0033] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other. To achieve the above objectives, this invention adopts the following technical solution.
[0034] The present invention will be further described below with reference to the accompanying drawings:
[0035] like Figure 1 As shown in (a) and (b) of the present invention, an underground pumped-storage system based on the reconstruction of underground space in an abandoned mine includes a surface water source reservoir 104, a vertical shaft 103, a newly excavated main horizontal shaft 105, a newly excavated secondary horizontal shaft 106, water pipelines 109 and 118, a water pump turbine 111, a transformer 110, and a cable channel 119. This system achieves pumped-storage energy by fully utilizing and reconstructing underground space resources in abandoned mines.
[0036] Specifically, the system is located within underground rock strata 102, covered by a soil layer 101. A surface water reservoir 104 is located on the ground surface to store elevated water, serving as the upper reservoir for the pumped-storage system. This upper reservoir is connected to the underground system via a water pipeline 109, which extends downwards along a shaft 103 to the underground powerhouse.
[0037] In the underground space, an underground tunnel network is formed by excavating a new main horizontal shaft 105 and multiple new sub-horizontal shafts 106 using excavation machinery 107, creating a lower reservoir. One end of the underground reservoir is sealed with a plug 108 to prevent water leakage or collapse.
[0038] The newly excavated underground tunnel network forms an underground reservoir. The newly excavated rock and soil are no longer transported to the surface, but are instead transported through connected tunnels to the goaf 115 of ore layers 1-112 and ore layers 2-113. The excavated rock and soil are then backfilled 116, and a goaf plug 117 is constructed at one end of the goaf. This provides stable support for the goaf 115, enhances the stability of the surrounding rock, and creates a good watertight environment, preventing water leakage or geological instability.
[0039] The system also retains and renovates the existing tunnel 114 to form an underground powerhouse, and constructs a new underground powerhouse on this basis, equipped with a water pump turbine 111. This turbine is a bidirectional device, capable of pumping water from the underground reservoir to the upper reservoir 104 during periods of surplus electricity, and also functioning as a turbine to generate electricity during peak electricity demand periods, driving a generator to output power. The water pump turbine 111 is connected to the surface power grid via a cable channel 119, enabling bidirectional power transmission. The cable channel 119 is laid along the vertical shaft 103, connecting to the underground transformer 110, and then to the high-voltage transmission line.
[0040] The vertical shaft 103 is not only used for vertical transportation but also serves as a combined channel for water and cable transport. Its top is equipped with a lifting mechanism 120 for material transport and personnel access. Figure 1 As shown in (b), when the underground-to-surface passage of the abandoned mine is an inclined shaft 103B, the inclined shaft 103B can serve as a combined passage for water and cable transportation, and can also be used for material transportation and personnel access.
[0041] Figure 2 is a schematic diagram of the horizontal layout of the concentric circular underground reservoir described in this invention, showing its tunnel network spatial structure composed of multiple annular cavities and radial channels. The specific descriptions of each numbered component in the figure are as follows:
[0042] The main horizontal shaft entrance section 201 serves as the passage connecting the underground powerhouse to the underground reservoir, marking the starting point for the excavation of the underground tunnel reservoir. The plug 217, located at the end of the main horizontal shaft, is used to maintain the reservoir water level and ensure sealing.
[0043] The outer annular cavity (first ring) is circularly distributed and forms the outer ring water storage space of the underground reservoir. There are multiple independent construction surfaces 202–208 on the outer ring of the annular cavity reservoir.
[0044] The inner annular cavity (second ring) is located inside the outer annular cavity and is connected to the outer ring through a radial channel to form a multi-level water storage structure. The inner annular cavity can be accessed through the independent construction face 202–208 of the outer ring and connected with the independent construction face 202–208 of the inner ring, enabling simultaneous excavation of multiple construction faces.
[0045] The radial tunnels are simultaneously excavated toward the concentric point 216 of the inner and outer rings, connecting all the radial tunnels.
[0046] The concentric circle structure achieves its core function in the following way:
[0047] High-density water storage: Multiple annular cavities are arranged concentrically to make full use of underground space and significantly increase the water storage capacity per unit area.
[0048] Parallel construction of multiple working faces: Multiple working faces 202–208 and 209–215 can be independently opened inside the annular cavity to achieve simultaneous excavation at multiple points, greatly improving construction efficiency.
[0049] Figure 3 is a schematic diagram of the horizontal layout of the array structure underground reservoir described in this invention, showing its networked spatial structure composed of multiple grid-distributed cavity units and transverse connecting channels. Specific descriptions of each numbered component in the figure are as follows:
[0050] The plug 325 is installed at the starting position of the main horizontal well excavation to maintain the reservoir water level and seal, ensuring safe operation.
[0051] The first branch of the main tunnel, 311, is the first reservoir tunnel branch road that extends from the position near the end of the tunnel, 325.
[0052] The second branch of the main tunnel, 312, extends from a position near the end of the tunnel, forming the second reservoir tunnel branch road.
[0053] The third branch of the main tunnel, 313, extends from the location near the end of the tunnel, 325, and is the third branch road of the reservoir tunnel.
[0054] During the construction of the first branch 311, the second branch 312, and the third branch 313 of the main tunnel, independent construction faces were opened up in the completed space. Independent construction faces 314-323 were set up on the first branch 311 of the main tunnel, independent construction faces 324-333 were set up on the second branch 312 of the main tunnel, and independent construction faces 334-343 were set up on the third branch 313 of the main tunnel.
[0055] The independent construction faces on the first branch 311, the second branch 312, and the third branch 313 of the main tunnel are constructed separately, excavating longitudinal tunnels to form a reservoir and creating a "chessboard" network. This structure allows excavation operations to be carried out in multiple cavity units, achieving multi-point parallel and efficient construction.
Claims
1. An underground pumped storage system based on the reconstruction of underground space in abandoned mines, characterized in that, include: The underground reservoir is constructed by building a new underground tunnel, which connects to the existing tunnels. The underground reservoir adopts a concentric circle structure or an array structure. The soil and rock backfill structure will backfill all the soil and rock generated from the excavation of the new underground space into the mined-out area; Above-ground reservoirs are reservoirs built on land or natural bodies of water on land, used to store water at high levels; A water conveyance system is constructed using the vertical shafts of abandoned mines to connect the above-ground reservoir and the underground reservoir, thereby enabling the circulation of water between the upper and lower reservoirs. Cable channels are constructed using the shafts of abandoned mines to connect underground transformers with above-ground switch stations and power grids, thereby connecting underground pumped storage units to the above-ground power grid. An underground power plant will be built using newly constructed underground space to install water pumps, turbines, and electric generators.
2. The system according to claim 1, characterized in that, The concentric circle structure includes multiple concentrically arranged annular cavities. One end of the concentric circle structure is the starting point for the excavation of the underground reservoir. A plug is set to enclose the reservoir and maintain the water level. During the excavation of the outer large-diameter concentric circle, a new construction face is opened on the completed excavation surface. The excavation moves towards the inner ring and simultaneously opens the inner ring reservoir. The inner and outer ring reservoirs are excavated at the same time. During the construction of the inner and outer ring reservoirs, a new construction face is opened and different radial straight reservoirs are excavated. At different positions of the inner and outer ring reservoirs, the inner and outer rings are connected by radial straight reservoirs.
3. The system according to claim 1, characterized in that, The array structure includes multiple horizontal and vertical straight reservoirs. The connection points of the horizontal reservoirs converge into an entrance tunnel. A plug is installed at the entrance tunnel to ensure the water level of the reservoir. During the construction of the horizontal straight reservoirs, the entrance tunnel splits into multiple straight reservoirs for simultaneous construction. A new excavation plane is opened in the part where the straight tunnel excavation is completed, and the vertical straight reservoirs are extended and excavated.
4. The system according to claim 1, characterized in that, For underground reservoirs constructed from newly built underground tunnels, a load-bearing sealing layer is installed between the underground reservoir and the surrounding rock.
5. The system according to claim 1, characterized in that, The existing tunnels of abandoned mines are used to form underground power plants or to transform existing tunnels into underground power plants for the installation of electrical equipment.
6. The system according to claim 1, characterized in that, Inclined shafts can also be used.
7. The system according to claim 1, characterized in that, The system is installed in underground rock strata, which are covered by a layer of soil.
8. The system according to claim 1, characterized in that, Construct a goaf plug at one end of the goaf area.
9. The system according to claim 1, characterized in that, The pump-turbine is a bidirectional operating device. During periods of surplus electricity, it acts as a pump to draw water from the underground reservoir to the upper reservoir. During peak electricity demand periods, it acts as a turbine to generate electricity, driving a generator to output electrical energy.
10. The system according to claim 5, characterized in that, Electrical equipment includes transformers.