Researchers at Imperial College London have found that pumped hydro storage could save up to £690m per year on energy costs by 2050.
SSE Renewables commissioned the independent study to look into the benefits of such schemes, which it intends to invest in.
The main benefit of long duration storage 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 October, SSE Renewables received revised consent from the Scottish Government for its Coire Glas hydro plant near Loch Lochy in the Scottish Highlands.
The proposed 1.5 GigaWatts at 30 GigaWatts per hour would double the current amount of pumped hydro storage capacity in Great Britain.
The report found that around three quarters of the savings to the energy system would be from the avoided capital expenditure in higher cost electricity generation technologies.
Professor Goran Strbac, who led the study, said: “The analysis demonstrated that new long duration pumped hydro energy storage located in Scotland can reduce system costs by providing a number of services to the net zero emission energy system.”
The research listed benefits including: reduced wind curtailment, an ability to create an electricity system that supports the grid jobs, reducing emissions and reduced network congestion between Scotland and England.
Mike Seaton, director of development at SSE Renewables, said: “The findings in this report support our view – that pumped hydro storage projects like Coire Glas have a huge role to play in the UK achieving its ambition of net zero carbon emissions by 2050 in the most cost-effective way possible.”
“However, there are commercial hurdles that we still need to overcome if such a large civil engineering project is to become a reality,” he noted.
“The current policy and market framework are not yet suitable for attracting investment in such large-scale storage projects, although the UK Government has set out its intention to address those barriers to investment.”
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