A new study by independent researchers from Imperial College London has found that just 4.5GW of new long duration pumped hydro storage with 90GWh of storage could save up to £690m per year in energy system costs by 2050, as the UK transitions to a net-zero carbon emission system.

Commissioned by SSE Renewables via Imperial Consultants the report – Whole-System Value of Long-Duration Energy Storage in a Net-Zero Emission Energy System for Great Britain – focused on the benefits of new long-duration pumped hydro storage in Scotland, as the current most established long-duration energy storage technology.

The main benefit of long duration storage compared to short duration batteries is being able to continuously charge up the storage with excess renewables and also discharge power to the grid for several hours or days when wind and solar output is low.

In its recent Energy White Paper, the UK Government set out that long-duration storage technologies like pumped hydro, would play an essential role in decarbonizing UK’s electricity supply by integrating renewable energy and maintaining security of supply.

The study, by Imperial’s researchers, found that 75% of the savings to the energy system would be from the avoided capital expenditure in higher cost electricity generation technologies that would otherwise be needed to meet the UK’s target of carbon neutrality by 2050 whilst meeting security of supply.