Multi-million-pound battery energy system planned for Swansea

Richard Youle, local democracy reporter

A multi-million pound battery energy system which could provide electricity for hundreds of thousands of householders has been proposed in Swansea.

The system, which includes a substation, could store excess electricity and then return it to the grid when demand rose.

Innova Renewables Ltd, which is seeking pre-application advice from Swansea Council, said large-scale storage of this type helped manage fluctuations in demand and could facilitate the expansion of intermittent renewable energy.

The batteries would have a total capacity of up to 500 megawatts, with one megawatt considered the equivalent electricity used by around 750 homes.

This means the system when fully charged could in theory provide electricity at very short notice for up to 375,000 homes, but only for a maximum of two hours.

The proposed site is in Felindre, near Abergelli Farm. The batteries and substation would take up some seven hectares – roughly seven rugby pitches.

Ecological survey

A small part of the site falls within a site of importance for nature conservation, and an ecological survey of the site has been undertaken.

A landscape buffer would be created at the site boundary to the north, north-west, north-east, and partly in the south to screen the development from the wider area.

The Welsh Government wants 70% of electricity used in Wales to be generated from renewable sources like wind and solar by 2030.

A cover letter on behalf of Innova Renewables said the battery system could operate at full power in less than a second.

The company’s director of planning, Simon Gamage, said of such energy systems: “They allow power to be temporarily taken off the electricity network and stored. And for it to be returned to the network at times of higher demand.

“For example – onshore wind farms will be generating power overnight, when demand for power is low. That power can be stored at sites like this and used later when demand is higher. This helps balance supply and demand and makes best use of the power available to the network.”

Technical studies

He added: “We are at an early stage in our project. Over the coming months we will be continuing to carry out specialist environmental and technical studies to refine our proposals, prior to holding a community information event to seek the views of interested local stakeholders, where we will present our proposals in detail.”

A company called Statkraft UK gained planning permission in 2021 for what it termed a greener grid park in Felindre to help stabilise the electricity supply.

The equipment is to comprise two large rotating stabilisers weigh some 350 tonnes each, batteries and inverters, and will essentially act as a shock absorber to provide stability when there are sudden fluctuations in the grid.

When planning consent was secured, Statkraft said that the £30 million project was expected to get under way in 2023.