A call to defer a scheme for a south Pembrokeshire national grid-connected electrical battery storage facility close to Pembroke Power Station after concerns were raised that it had no actual connection in the plans was defeated by just one vote.

In an application before the July meeting of Pembrokeshire County council’s planning committee, the scheme by Sirius EcoDev (Lambeeth) Ltd for the installation of a Battery Energy Storage System (BESS), associated infrastructure including a 132kv substation and engineering works on land east of the Greenlink Converter Station, near Pembroke Power Station, was recommended for conditional delegated approval.

A report for planners said the BESS compound of 46 battery containers and 23 power conversion systems would have a 40-year lifespan and the “proposed point of connection to the Grid would be approximately 300m to the north of the BESS compound, albeit that this does not form part of the application”.

The scheme would provide electricity storage equivalent to supplying over 20,819 homes, the report said.

The application described the need for the BESS infrastructure, the report said: “Renewable energy supply from wind and solar is intermittent with a fluctuating supply to the Grid. As renewable energy provision increases, there is a risk of increased energy supply fluctuations and therefore increased need for facilities that store energy so that supply can be regulated. BESS do not create carbon emissions or generate electricity but provide a balancing mechanism drawing electricity (charging) when levels on the network are above that of demand.

“When levels of electricity on the grid are below that of demand the electricity stored in the batteries can be fed back (discharged) onto the network to meet the demand. BESS provides sub-second response times, so offer a reliable solution to a number of the Grid’s balancing issues thus supporting the development and deployment of low carbon intermittent energy technologies."

Concerns about the scheme in its current form were raised at the July meeting by local councillor - and county council chairman - Steve Alderman, who later called for a site visit to view the application.

Cllr Alderman raised concerns about potential safety issues and said the current plans would have “a site full of batteries and no connection to charge them”.

Cllr Alderman added: “It does bother me; we have a site, in between two powerful electricity sites, it has no planned connection.

“I’m really not happy about this at all, there’s 132kv between two lines, that seems to be a serious safety issue.”

He later said he was “all for building storage solutions,” adding “the future generations are going to need it”.

Calling for a site visit, he said: “It bothers me, I would normally be all for this. We have a site, but what we don’t have is a facility to use these batteries, both for charge and for discharge, it has no way of charging or discharging, I don’t get this; I would like to see it deferred until we have a line that is useable.”

Cllr Jordan Ryan told members they should think “very carefully” in voting to pass the scheme when “there’s all these questions up in the air”.

“Cllr Alderman has got some very valid questions; I think we should be backing the local member,” Cllr Ryan added.

Members heard details of the cable route had been removed from a previous application to that presented to committee.

The site visit call was defeated by seven votes to six, members later agreeing to delegated approval for the plans.