Blueprint Ready for Com mercial Mine Energy Storage Capacity in Sweden

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Blueprint Ready for Commercial Mine Energy Storage Capacity in Sweden

swedish Mining innOvatiOn, a cOMbined OrganizatiOn Managed by Sweden's Innovation Agency, government research council Formas, and Sweden's Energy Agency, has given financial support to a blueprint for what might become the world's first commercial underground mine storage facility.

An international consortium of mining and energy companies is now putting together the plans for the facility in Bergslagen, Sweden, which has a long history of mining. The blueprint, which will detail every stage of the process from the initial landowner and authority clearance to a grid-connected energy storage and supply facility, will be submitted to the European Union in the near future. The partnership will be led by Mine Storage, a Swedish grid-scale energy storage company.

It will include Swedish mining companies Boliden and Lovisagruvan, energy provider Mälarenergi, worldwide hydropower equipment manufacturer Voith Hydro, and engineering and design firm AFRY. According to Thomas Johansson, co-founder and CEO of Mine Storage, the award from Vinnova, which is part of the agency's Swedish Mining Innovation project, "is a clear sign of the rising interest in the global potential of utilizing abandoned mines for energy storage."

Mines that have been abandoned are being repurposed as massive batteries.

The idea is to repurpose abandoned mines into giant "batteries" to help balance the rising percentage of intermittent generation, effectively establishing a "cross-sectional" project that addresses numerous environmental challenges. "Many countries have thousands of unused and orphaned underground mines," says Stefan Sädbom, a long-time exploration geologist with decades of expertise in the mining and metals industries and who presently serves as an advisor to Mine Storage.

In the face of growing electrification and variable energy prices, large-scale and long-duration energy storage is becoming increasingly important. "Much more than today, the world needs to store created energy and govern the energy supply," Johansson stated. Pumped storage hydropower now provides more than 90% of energy storage due to its established technologies that provide quick reaction and adaptability to fluctuations in energy demand. He did observe, however, that "most countries lack the height disparities required in the topography for above-ground storage facilities." "This is where the mine store is located."

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Mine Storage's concept is reviving abandoned mines as giant "batteries" to help the grid balance. The turbine and pump equipment make up the powerhouse. Pumping water to a higher height stores energy from the grid. When water is released into the lower reservoir and passes through the turbine in the powerhouse, energy is returned to the grid.

Mine Storage has floated a solution that effectively duplicates classic pumped storage with upper and lower reservoirs in underground mines since its founding in 2020. (Figure 1). "Closed mines are naturally filled with water (groundwater)." We investigate a wide range of mines, from those that have been closed for decades to ones that are still operational," Johansson told POWER. "While existing underground caverns and volumes may be sufficient in certain circumstances, we may need to expand to obtain necessary volumes in others."

Mine Storage evaluates a proposed site's geotechnical qualities, such as rock stability; hydrological requirements, like the sort of head and mine design; environment; and operational questions, such as the necessity for draining and water quality, in order to determine its viability.

It also conducts several other assessments, including grid-connections, construction needs, health and safety, and water supply; a commercial evaluation, which includes preliminary financial forecasts of the business case; a rights and regulatory part, which includes discussions with land and concession holders and assessing the legislative and permitting prerequisites; and a market assessment, which provides for gauging beneficial policies, regulation, incentives, and potential parity; and a market assessment, which includes discussions with land and concession holders and assessing the legislative and permitting prerequisites.

Figure 1

Mine Storage evaluates a proposed site's geotechnical qualities, such as rock stability; hydrological requirements, like the sort of head and mine design; environment; and operational questions, such as the necessity for draining and water quality, in order to determine its viability.

A Lucrative Prospect

Johansson recognized that the notion necessitates a long-term investment, which might be substantially more expensive than batteries.

The projects may have a fair levelized cost of storage because Mine Storage's pumped storage plants under development range in power output from 15 MW to 400 MW and energy output from 30 MWh to 800 MWh for a single discharge.

"A mine storage facility is an infrastructure/energy project with very high long-term value, and our financial calculations show profitability," Johansson added. Mine Storage has attracted a number of noteworthy investors due to the concept's potential commercial case. Voith Hydro is one of them, with a significant investment in pumped hydropower technology and hydropower flexibility. Mine Storage partnered with Voith Hydro in June 2021 to study early project development at two specific sites in Sweden and create the necessary technical solutions.

This summer, Mine Storage also signed a collaboration agreement with Ellevio, one of Sweden's most prominent regional grid operators, to investigate how a mine storage system could alleviate grid congestion. The startup announced in the fall that it had secured an oversubscribed seed round, providing the funds and skills it needed to scale up.