Representative Director, President and Chief Executive Officer Shingo Ueno of Sumitomo Corporation, Tokyo, via Summit Transition Partners Limited – STP, which happens to be a joint venture founded with a majority stake held by Sumitomo Corporation and established with TPK Holding Co., Ltd., Head Office at Taipei, Taiwan, whose Chairman is Michael Chao-Juei Chiang, has agreed to invest in several large-scale BESS by Gresham from London, UK, a leading investor in the UK battery energy storage sector. Apparently, Sumitomo Corporation has also formed a strategic alliance in battery energy storage with Gresham House Limited, which happens to be the fund manager of GRID.
It is well to be noted that around 50% of the electricity in the UK is supplied from renewable sources. Interestingly, policy support is in a way encouraging large-scale deployment of BESS so as to make sure of a balanced electricity supply. In fact, Sumitomo Corporation has been actively involved in renewable energy businesses such as offshore wind in the UK and power trading businesses. This initiative and partnership will grow the large-scale BESS business of the company and help create a more robust and financially viable power system.
Project Description
Notably, the projects comprise five utility-scale BESS projects which need to be developed across the UK, with an overall planned capacity of roughly 694 MW. STP is initially putting funds into the first three projects totalling 397 MW, with construction anticipated to start within this financial year. Development of the other two projects, totalling 297MW, over which STP has obtained exclusive rights, will be advancing, allowing for the phased development of a solid portfolio.
Background to Business Engagement
The UK government has set itself a few challenging targets for renewable energy, and the function of grid-scale BESS in promoting supply-demand balancing as well as grid stabilisation has grown increasingly important. At the same time, regulatory structures that support the BESS sector are additionally being strengthened, and consumer demand is expected to grow more in the years to come. In light of this, Sumitomo Corporation has been seeking opportunities in the BESS market in the UK. In July 2025 the company entered into a full MoU with the Department for Business and Trade’s Office for Investment under the UK government concerning the promotion of business investment within the UK. This BESS project is one of the initiatives under the MoU.
It is worth noting that GH, which is Sumitomo Corporation’s partner in the initiative, is an established developer and operator within the UK BESS sector with an established track record of constructing approximately 1 GW, roughly 15% of the BESS capacity in the UK. The partners will combine development and operational capacity with the business platform and expertise of the BESS so as to further expand BESS businesses across the globe, including in the UK, as well as contribute to a consistent electricity supply that encourages wider utilisation of renewable energy.
Sumitomo Corporation Battery Energy Storage Developments
The fact is that Sumitomo Corporation has a proven record in the BESS value chain when it comes to Japan with asset ownership and project development as well as operational management, which includes a battery energy storage project at Koshikishiima Island based out of Satsumasendai City in the Kagoshima Prefecture and also an EV battery station business located in Chitose City on the Hokkaido island. In addition, the company has developed advanced capabilities to optimise grid-connected battery storage assets across Japan by means of its 100%-owned subsidiary, OPTECH Energy Co., Ltd. The company utilises conventional electricity markets to improve the performance of assets and create value.
Interestingly, Sumitomo Corporation will capitalise on its partnership deploying large-scale BESS by Gresham so as to expand its battery energy storage business globally with Japan as well as the UK as strategic hubs by leveraging these capabilities. These efforts are targeted at aiding the stabilization of power systems behind the global energy markets by providing stronger and adaptable power systems.