A plan for a battery storage plant on Green Belt land in Mill Hill has been thrown out by councillors.

The proposal to build the facility on fields next to the National Grid substation in Partingdale Lane was unanimously rejected by members of Barnet Council’s planning committee B during a meeting on Wednesday.

Town hall planning chiefs had backed the scheme, claiming in their report that its support for renewable energy and tackling climate change constituted “very special circumstances” that would allow development on the Green Belt under the council’s policy.

But the plans met with fierce opposition from residents, with the council receiving more than 900 letters of objection and only two letters in support of the scheme during a public consultation.

Designed to store power at times of excess supply so it could be used at periods of high demand, the proposal would have seen 20 containers rising to almost three metres high, housing battery storage systems installed on a 0.49-hectare greenfield site, along with transformer stations, fencing and CCTV cameras.

According to the planning report, the scheme would help the National Grid to respond to “increasing fluctuations in generation” caused by the greater use of renewable energy sources and would “support the aims of meeting the UK’s net zero carbon emissions commitments and the climate emergency”.

Roger Selby, of the Mill Hill Preservation Society, told Wednesday’s meeting the special circumstances that would allow building on the Green Belt had not been demonstrated. 

Pointing out that the land was a site of metropolitan importance for nature conservation and “home to many rare and protected species”, he claimed the facility would “damage ecological networks and hinder wildlife movements”.

Roger said the noise level produced by “20 huge battery containers” was likely to be “considerable” and warned it “would impact on the lives and the physical and mental health” of the residents of nearby roads “for the next 40 years or longer”.

Gary Temple, chair of Hillview Road Residents’ Association, said noise from the proposed facility’s cooling fans would add to the “already continuous hum” coming from the substation, and this “noise pollution” would “deeply affect residents”.

He warned there were “risks to health and to life with this installation”, citing reports of fires and a “fatal explosion” at similar facilities.

The committee also heard objections from councillors John Hart, Val Duschinksy, Elliot Simberg, and Hendon MP Matthew Offord.

Philip Roden, a planning agent for the applicant, told the meeting that the Conservative government and National Grid had recognised that energy storage would play a “critical strategic role in supporting the move to net zero”.

He added: “The wider environmental benefits and the strategic need for storage represents a very special circumstance that outweighs harm to the Green Belt.”

Philip claimed the site was of “limited ecological value” and that new landscape proposals would “enhance biodiversity”.

Under questioning from councillors, the agent said the applicant had looked for industrial land but had been unable to find any suitable sites near to the substation. He added that Mill Hill was one of the “very few locations” in the UK with spare capacity to accept a 50 megawatt facility such as the one proposed.

After hearing the evidence, committee members voted against officers’ recommendation to approve the scheme. They then voted in favour of a motion to refuse the scheme on the grounds that it would be an inappropriate development on the Green Belt, and that the very special circumstances did not exist to outweigh the harm that would be caused.