A group of fourteen assembled at Wormald Green last Friday morning to learn about the Harmony Battery Energy Storage System (BESS) located there. We were welcomed by Tessa and Alastair from the company who did a good job in explaining some of the details.
Alastair explained that the site was selected for its proximity to the local sub-station. The closer the site, the more sustainable it is, due to reduced installation costs and transmission losses. Harmony Energy has taken on a 40 year lease of the land, in anticipation of changing technology. At the end of the lease the land reverts to agricultural use.
Battery energy storage systems help renewable energy by storing electricity when generation exceeds demand (for example on sunny or windy days) and releasing it when it is needed, keeping the grid stable and providing balance. The batteries installed at Wormald Green are Envision Energy batteries and the site was energised in 2024. We were told that the life expectancy of a battery is 20 years on average. After that, the supplier is responsible for its disposal. According to Harmony’s website, batteries are either recycled or refurbished. One would hope that the supplier would still be around when the time comes!
One of our first questions was “is the site noisy?” Batteries do not make any noise themselves, however their fan cooling equipment operates intermittently and this creates the audible noise element. Consideration is given to this when preparing a planning application and mitigation in the form of bunds or acoustic fencing are provided where necessary.
As naturalists, we were interested in Harmony’s environment policy. This is freely available on their website. Harmony says it is committed to reducing the negative impact of their activities on nature. For UK sites, the mandatory 10% biodiversity net gain target should be exceeded where possible. We were also shown evidence of responsible water management, with an integrated water drainage system at the bottom of the site.
Some of us (mostly me) found it strange that the site runs on an unattended basis, with technology continually monitoring the batteries and the site as a whole. Despite this, and the unexpectedly cold weather, I found our morning visit very enjoyable. One reason being that I was starting from a knowledge level of almost zero, so all these new facts were bound to be interesting. If anybody would like to learn more about renewable energy infrastructure projects, then it is worth looking online at Harmony Energy’s website: https://harmonyenergy.co.uk/battery-energy-storage-systems/
Finally, we would like to thank Harmony Energy for accommodating us so well, and we wish the company every (sustainable) success for the future.
Sonia Starbuck