Fotowatio Renewable Ventures’ UK partnership kicks off delayed 198MWh battery storage project

By Cameron Murray
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Fotowatio Renewable Ventures (FRV) and UK developer Harmony Energy have announced the initial construction works of the Clay Tye battery energy storage system (BESS), which they claim is the UK’s largest in construction. 

Clay Tye is in Essex, southeast England, and will be a two-hour duration system with a power rating of 99MW and an energy capacity of 198MWh. It will use 52 Tesla Megapacks and the EV giant’s optimisation platform, Autobidder.

Some readers may be confused by this announcement coming 10 months after Harmony announced that work had “started immediately” on the project. That signified the start of overhead line work, after which there was a short delay with an announcement on 18 July signifying the official start, sister site Solar Power Portal was told by a source close to the project. 

To read the full version of this story, visit Solar Power Portal.

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13 October 2026
London, UK
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