12 June 2012

ETI invest £14m in energy storage breakthrough with Isentropic

ETI invest £14m in energy storage breakthrough with Isentropic - kick starting UK technology development and creating new jobs

The Energy Technologies Institute (ETI) is investing £14 million in a five year project led by Hampshire based SME Isentropic Ltd to demonstrate the feasibility of a revolutionary new approach to storing electricity at grid scale. The deal will enable Isentropic to grow and triple its workforce to 30 by the end of the year. As part of the agreement ETI will become a minority equity shareholder in Isentropic.

Isentropic is a private company, founded in 2007 to exploit its Pumped Heat Electricity Storage (PHES) technology for large-scale energy storage. Using Isentropic’s innovative combined heat pump/heat engine, electricity is used to create a large temperature difference (500 C hot and -160 C cold), which can then be stored in two low cost gravel silos. Recombining the hot and cold regenerates the electricity with an overall efficiency of 75%.

With a budget of £15.7 million, the project will develop and demonstrate a cost-effective 1.5MW/6MWh energy storage device that will operate on a UK primary substation owned by Western Power Distribution (WPD) in the Midlands. It is hoped that once tested, it could be rolled out across the UK where there are approximately 5,000 substations with a suitable power range of between 12MW and 24MW, bringing with it cost benefits for consumers of electricity.

Business Secretary Vince Cable said:

As our energy supplies change, finding innovative ways to store energy will become an increasingly important factor in the transition to a green economy and I welcome this investment by the ETI in what is a leading edge technology developed in the UK.

“The UK needs to seize the opportunities presented by the transition to a green economy and finding low cost solutions to electricity storage offers significant growth opportunities while also helping us meet the challenges of climate change.

Dr David Clarke, Chief Executive of the ETI, said:

Isentropic are innovators in the field of electricity storage. Our investment strategy here is two-fold. Firstly we are providing financial support to allow the company to develop this technology further and staff up accordingly. Secondly we are using our position to accelerate and expand the testing of this new UK technology to seek to identify the large- scale deployment potential to help provide affordable clean and secure energy solutions for the future.

“Our modelling has shown there is huge potential and a need for storing energy as part of the UK’s energy mix for 2050, as this will help to allow affordable renewable sources to expand and reduce the UK’s carbon emissions.”
James Macnaghten, Chief Executive of Isentropic, added: “The equity investment and project funding provided by the ETI represents a huge vote of confidence in our unique Pumped Heat Electricity Storage technology. We believe this investment and project will allow us to demonstrate further our leading position in the fast growing energy storage market.

Notes to Editors:
For further information, please call Richard Robinson at the ETI on 01509 202026 or 07500 049626.

● The Energy Technologies Institute (ETI) is a public-private partnership between global industries – BP, Caterpillar, EDF, E.ON, Rolls-Royce and Shell – and the UK Government.

● Public sector representation is through the administration of the Department for Business, Innovation and Skills, with funding channelled through the Technology Strategy Board and the Engineering and Physical Sciences Research Council. The Department of Energy and Climate Change are observers on the Board.

● The ETI is focused on accelerating the deployment of affordable, secure low-carbon energy systems for 2020 to 2050 by demonstrating technologies, developing knowledge, skills and supply-chains and informing the development of regulation, standards and policy.

About Isentropic Ltd:

• Isentropic’s Pumped Heat Electricity Storage (PHES) technology is environmentally friendly, has no geographical constraints, is compact and has the potential to dominate the large-scale electrical storage market because it offers the prospect of being the lowest cost solution to the intermittency problems of renewable energy sources, such as wind. See

About Western Power Distribution:

• Western Power Distribution (WPD) is the distribution network operator for the Midlands, South West England and South Wales, and is responsible for delivering electricity to approximately 7.7 million customers in the UK.

• WPD is not an electricity supply company and does not bill customers in the UK. Its responsibility is to distribute electricity from the point of generation to homes and businesses.

Request for proposals

View all proposals

Learn more about the ETI



Invested in projects


Programme areas


Projects commissioned

Download the ETI brochure