SSE Renewables has called for urgent investment in Long Duration Electricity Storage (LDES), following a report from Aurora Energy Research which shows that up to 24GW of LDES – equivalent to eight times Britain's current installed capacity.

The report demonstrates the potentially critical role of LDES in the GB energy system. It outlines how Britain's electricity system will require a range of flexible home-grown long duration storage technologies, including pumped hydro storage, if it is to be cost-effectively and securely decarbonised by 2035.

Aurora's report demonstrates the benefits LDES could provide to the GB energy system by contributing towards security of supply and reducing emissions, costs and reliance on imported gas. The report states that introducing LDES technologies in large quantities in GB by 2035 can reduce carbon emissions by 10 MtCO2 annually, while cutting system costs by £1.13 bn (2.5%) and the country's reliance on gas by 50 TWh.

The Aurora report, entitled 'Long duration electricity storage in GB', was conducted for a consortium of public and private sector organisations including SSE Renewables.

SSE Renewables is actively progressing the development of its 1.5GW Coire Glas pumped storage project in Scotland's Highlands. Coire Glas would be the first large-scale pumped hydro storage scheme to be built in Britain for more than 30 years and would have the standalone capability to more than double the UK's electricity storage capacity and significantly scale up system flexibility. Investment by SSE Renewables into the project could be unlocked if the UK Government establishes a policy and market framework that appropriately values LDES technologies.


Stephen Wheeler, Director of SSE Renewables, said: "Cost-effectively and securely decarbonising the UK's electricity system by 2035 will require a range of flexible home-grown long duration storage technologies.

"This timely study by Aurora finds that to achieve the government's ambition, an eight-fold increase in long duration storage capacity is needed. This amount of storage capacity will not only play a major role in reducing emissions, but also significantly reduce the UK's reliance on imported gas and in return, keep household energy bills lower and less volatile.

"The introduction of a new policy mechanism such as the Cap and Floor could unlock the investment required in projects such as our 1,500MW Coire Glas pumped storage project which has the standalone capability to more than double the UK's total electricity storage capacity and significantly scale up system flexibility."

The UK's Net Zero strategy to decarbonise the power system fully by 2035 is subject to security of supply being maintained. With gas-fired generation currently the main flexible resources available to balance intermittent solar and wind, Aurora's report finds this target is unachievable without urgent investment in viable low-carbon alternatives.

LDES includes pumped hydro storage and a range of innovative new technologies that can store electricity for four hours or more in order to supply firm, flexible and fast responding energy that is valuable for managing a high renewables system by enabling increased utilisation of renewables, enhanced system stability and resilience. LDES technologies can respond to supply and demand variations caused by daily peaks, weather events and seasonal patterns.

The need for LDES has been recognised by policymakers but at present, high upfront costs, long lead times, a lack of revenue certainty and missing market signals, lead to underinvestment. Policy support and market reforms can provide revenue certainty and address missing markets to recognise the full value of LDES to enable the deployment of these vital technologies.

Coire Glas, located on the shores of Loch Lochy near Invergarry, will be the first large scale pumped storage scheme to be developed in the UK for more than 30 years. Earlier this month hydro construction specialists from around the world were invited by SSE Renewables to submit tenders for construction of the proposed pumped hydro storage scheme. Ground was broken on investigatory works at the site late last year.