Underground energy storage specialists Gravitricity has signed a collaboration agreement with Czech electricity flexibility aggregator Nano Energies to develop commercial routes to market for their gravity storage technology.
In February the Edinburgh based storage firm unveiled plans to transform the former Darkov deep mine in the Czech Republic into a massive gravity energy store – which could be a pathfinder for projects Europe-wide. Gravitricity plans to store energy by lowering and raising a single massive weight suspended in the Darkov mine shaft.
“The Czech Republic is our home market, and we are experts in the field of flexibility aggregation,” explains Stanislav Chvála, CEO of Nano Energies. Gravitricity's technology is able to respond to grid fluctuations very quickly and flexibly in terms of megawatt volume. We could thus involve them in our virtual power plants, which help balance the grid in the way that nowadays primarily coal and gas-fired power plants are able to do. It is a long-life technology, well suited to integration with existing grid infrastructure. It can cycle rapidly from charge to discharge without any loss of performance over many years, and it delivers extremely fast response times of less than a second. This makes it a very attractive package to grid operators seeking grid balancing and fast frequency response services.”
In February, Gravitricity signed a memorandum with DIAMO, the Czech state enterprise charged with mitigating the consequences of coal mining in the republic, where the two parties committed to work in tandem to seek funds to turn the decommissioned mine into a 4 MW/2MWh energy store.
Gravitricity has also signed a memorandum with the Institute of Geonics, whose Geomechanics and Mining Research department hold extensive knowledge and understanding of the mining infrastructure in the Czech Republic. The Institute of Geonics have provided strong support to Gravitricity in recent years and are expected to be closely involved in the development of the Darkov mine project.
The Edinburgh firm has already demonstrated a scale version of its technology in Edinburgh – built in partnership with Dutch winch specialists Huisman – and now plans to build full-scale schemes in the UK and worldwide. Future multi-weight systems could have a capacity of 25 MWh or more.
Worldwide, Gravitricity estimates that there are around 14 000 mines which could be suitable for gravity energy storage.
Image: CGI cross-section of a Gravitricity system (courtesy of Gravitricity)