"Gravitricty Ltd is developing a mechanical technology using gravitational potential for grid-connected electrical energy storage. The scale is currently around 1MW with potential for up to 20MW peak power, and energy storage from 250kWh to 10MWh per cycle. Combination with CAES, using the same vertical shaft as a pressure vessel, could increase the energy stored threefold. The technology has major advantages including rapid response (<1s to full power), high energy efficiency (75-85% round-trip efficiency), very long lifetime (50 Yrs+ for major components) with no cyclic degradation, and locational flexibility. During this 12 month project Gravitricity will work with heavy-lift experts Davy Markham and Deeptek to:

A) develop detailed designs for cost reduction in future commercial projects (both in existing mineshafts and in purpose sunk shafts);

B) test modular components of the Gravitricity system under gravity and under mock-grid conditions at the Power Networks Demonstration Centre; and C) identify sites and begin environmental and geophysical assessment of sites for our full-scale prototype project, which will be built in 2019 or 2020\."