Gresham House hits 1 GWh battery storage milestone through capacity upgrades 

Gresham House Energy Storage Fund has increased its operational capacity to over 1 GWh, following the completion of augmentation works at two existing projects. The utility-scale BESS investor has extended its Enderby and West Didsbury projects, resulting in both sites trading at increased capacity.  

Augmentation work at the two sites involved upgrading each 50 MW BESS from 1-hour to 2-hour duration, resulting in 100 MWh of additional operational capacity. Both sites were designed to incorporate these upgrades from inception, according to Gresham House.

In total, Gresham House has added 117 MWh of capacity to its operating projects in the first half of 2024. Extension works at the fund’s BESS in Arbroath were completed on 2 April 2024. Gresham House plans to add a further 220 MWh of capacity through four more augmentation projects before the end of the year. 

Its operational portfolio currently totals 790 MW/1030 MWh in the United Kingdom, representing a subtantial share of the nation’s operating BESS fleet. For comparison, Q1 2024 figures from analytics platform Modo Energy recorded cumulative BESS capacity of 3.9 GW /4.9 GWh in Great Britain at the end of the quarter. 

In the fund’s most recent annual report and financial statements, published in April 2024, Gresham House set out its intention to carry out augmentation work at its sites in Melksham, Penwortham, Coupar Angus, and Nevendon, in addition to the recent upgrades.

John Leggate, chair of Gresham House, commented on the augmentation strategy. “The Board has taken the decision to focus part of its capital allocation on upgrading certain existing sites which it believes is an efficient use of capital, derisks project execution and improves the portfolio’s revenue potential,” he said.  

Leggate also highlighted the revenues secured through Gresham House’s recently announced tolling agreement with Octopus Energy as proof of the “growing range of opportunities” available through balancing electricity supply and demand, while also “reducing the volatility of these revenues.” 

Ben Guest, fund manager at Gresham House, added that it is “well documented” that the UK BESS market is moving toward a trading strategy dominated environment. “The upgrade of these two sites to 2-hour duration enables these projects to capitalize on that trading opportunity,” he said.