Wilson t2 ecotrans distribution transformers at bumpers battery energy storage system (bess)

Projects
Bumpers BESS

99MW/198MWh Europe's joint-largest BESS at the time of energisation

Bumpers Battery Energy Storage System (BESS) is a significant energy storage facility located in Princes Risborough, Buckinghamshire, UK. Developed by Harmony Energy Income Trust plc (HEIT), the project has a capacity of 99 megawatts (MW) and an energy storage capacity of 198 megawatt-hours (MWh), making it one of the largest BESS installations in Europe. Bumpers utilises 56 Tesla Megapack 2XL lithium-ion batteries, each pair connected to a Wilson Power Solutions MV transformer supplied in moss green.

Surrounded by a 17.5MW Solar Photovoltaics Farm, Bumpers Tesla Megapacks and Wilson Power Solutions assets interact with the grid using Tesla’s Autobidder platform, a real-time trading and control platform that provides asset management and optimisation based on value. Crucially, this allows the facility to help balance the UK electricity grid whilst maximising revenue, further emphasising BESS's role in reducing the curtailment of renewable energy generation.

Upon energisation, Bumpers was the joint-largest BESS in Europe by MWh. We supplied Bumpers with twenty-eight 4200kVA 33kV/480V-480V Wilson T2 Ecotrans® Large Distribution Transformers connected to Tesla megapacks and two 150kVA 33kV/415V Wilson Auxiliary Earthing Transformers to power ancillary services on the site and provide protection. The site also has a Wilson UKPN-compliant packaged substation. As part of the planning permission, the transformers were requested to be painted in fashionable moss green, blending in with the surroundings and offering a beautiful contrast against Tesla's white megapacks.

Sector	Battery Energy Storage System
Developer	Harmony Energy
Project	Bumpers 99MW/198MWh
Location	Princes Risborough, Buckinghamshire
Scope of Work	Twenty-eight 4200kVA 33kV/480V-480V Wilson T2 Ecotrans® Large Distribution Transformers Two 150kVA 33kV/415V Auxiliary Earthing Transformers 315kVA 11kV/433V UKPN PSS Transformer with VRN2a RMU

"The success of our sites is only possible through the development of strong partnerships, and Wilson’s has been a valued partner throughout our growth. Their product innovation, engineering excellence and strong sense of social and environmental responsibility underscore their team’s proficiency in addressing complex project demands and showcasing technical expertise."

Peter Kavannah, CEO - Harmony Energy

Peter Kavanagh Harmony Energy credit Harmony Energy

MV transformers

Tesla Megapacks

200 MWh

in a single charging cycle

Erika Wilson - Managing Director - Wilson Power Solutions

“Battery energy storage systems are essential to unlocking our Net Zero potential, and getting the correct specification of transformer has never been more paramount. We’ve made significant investments to our facilities to elevate our transformer offer as we continue to look to partner with forward-thinking companies and developers such as Harmony Energy.”

Erika Wilson - Managing Director

Wilson Power Solutions