A PROPOSAL has been unveiled to build the UK’s first below ground gravity energy storage system in Ryedale.

Scottish energy storage firm Gravitricity is to apply to Ryedale District Council with its plan – which could see the construction of the ground-breaking plant on the site of the former gas generator at East Knapton.

If completed, it could store up to four megawatt hours (4MWhs) of electricity – sufficient to power more than 9,000 homes for an hour.

Gravitricity is developing technologies to store renewable energy by lifting and lowering heavy weights in an underground shaft.

They believe their simple idea can store energy more cheaply and with less environmental impact than batteries – and will be a vital technology as we rely increasingly on intermittent renewable energy.

Last summer they demonstrated their technology with an above-ground demonstrator in Edinburgh.

In September, they secured a £912,000 grant from the Department of Business Energy & Industrial Strategy (BEIS) to develop feasibility plans for a purpose-built below ground system – which would raise and lower multiple weights in a single shaft.

The company has identified Knapton Energy Park, the former Knapton Generating Station, at East Knapton owned by Third Energy, as an ideal location for this first of a kind energy store.

The Scots firm has already written to local residents and will hold a public information event, prior to submitting a planning proposal.

If the application to Ryedale District Council (RDC) is successful, this could pave the way to a further BEIS grant to part fund the works.

This project would take place over two years and would involve sinking a purpose-built shaft up to 10 metres in diameter and up to 250 metres deep.

Charlie Blair, Gravitricity’s Managing Director, said: “Knapton Energy Park is an ideal site for this proposal. The surrounding geology is very stable and there is an existing grid connection at East Knapton.

“Our technology soaks up excess renewable energy by lifting multiple weights in a shaft – and then releases it by lowering the weights. It stores energy in the same way as a grandfather clock but on a massive scale.

“In the future, many of these purpose-built energy stores could be located wherever required, to store renewable energy for use when needed. This would help stabilise the grid and lower consumer costs.

“If this planning proposal is approved, it will help us raise the public and private funds that would make this demonstration project a reality.

“There are a number of steps in this process. We will submit our feasibility study to BEIS later this year and we hope our application is viewed favourably by RDC.”

Shaun Zabłocki, Third Energy Operations Director, said: “The proposed development is a prime example of how progressive and creative engineering can provide market disrupting solutions to the UK’s energy storage demands. This type of development would be of great benefit to Ryedale, and North Yorkshire, and would really emphasise how the north of the UK is working together to lead the way in this sector.

“Third Energy is delighted to be able to provide support to Gravitricity with the proposed development and is excited to be a part of this project. The aims of the proposal are consistent with our own strategy of repurposing our Knapton site and other legacy infrastructure into renewable energy generation and storage assets.”

Last month Third Energy, which owns 12 wells in Ryedale, announced it has commissioned investigations to establish if they can be repurposed for geothermal energy. RDC secured a £50,000 government grant to help fund the work. This sum has been match funded by the company, which has new owners and is no longer interested in using the wells for fracking or gas extraction.

The wells are thousands of feet deep and one is known to contain water up to 80-90° Celsius.

The feasibility work is ongoing. If shown to be viable, the wells could heat private homes, as well as leisure, commercial or agricultural buildings – bringing significant benefits for communities and the local economy.