Some 2.5GW of BESS projects in the UK have won contracts across the T-1 and T-4 capacity markets (CM), announced in a week which also saw project financings worth a combined c.£1 billion, including from Zenobē, Constantine and Quinbrook.
BESS wins 2.5GW across one-year and four-year CM auctions
The National Energy System Operator (NESO) released its provisional auction results for the one-year ahead (T-1) and four-year ahead (T-4) capacity market (CM) auctions, handing out around 2.5GW of contracts to large-scale battery energy storage system (BESS) projects.
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The T-1 capacity auction for delivery in 2025/2026 concluded on 5 March 2025 at 10am, resulting in 7,936.289MW procured across 246 Capacity Market Units (CMUs). The clearing price was set at £20.00/kW/year.
In total, 725.813MW of BESS capacity was awarded in the T-1 auction, across 78 CMUs, making up 9.15% of total awarded capacity. Furthermore, eight units with a total of 127.856MW of capacity excited the market.
The T-4 auction meanwhile concluded on 11 March at 11:30am, and 43.1GW was procured across 669 CMUs. The auction cleared at a price of £60/kW/year, down from last year’s all time high clearing price of £65/kW/year.
Around 18.861MW of capacity was awarded for solar generators, across 12 market units, while 111 battery energy storage system (BESS) CMUs were awarded a total of 1.782GW of capacity.
BESS represents 16.59% of all the total awarded capacity in this auction. Pumped storage was awarded 3.77% of the total capacity granted in this T-4 round, at 1.623GW across eight CMUs. Gas meanwhile won around three-quarters of the total.
See the full article with more details on the winning projects on Current.
Zenobē lands financing for 400MW Eccles project
BESS developer-operator Zenobē has announced that it has successfully financed its Eccles BESS project in Scotland and started construction.
The total debt raised for the 400MW/800MWh project was £220 million (US$285 million), which the company says is one of the largest finance raises for a standalone BESS project ever made in Europe.
The Eccles BESS is the final part of the firm’s £750 million investment in Scotland. Zenobē’s Blackhillock BESS, a 200MW/400MWh project located near Inverness, recently began commercial operations, and is set to expand to 300MW/600MWh later this year.
Constantine Energy Storage secures £180 million financing for BESS portfolio
Owner-operator Constantine Energy Storage has landed a £180 million financing deal with a multi-national banking consortium for a 612MW BESS portfolio across the UK.
The nine-asset BESS portfolio is the biggest portfolio ever financed in Europe, according to Constantine, and all of the assets are located in England and Wales.
According to Nord/LB, one of the financiers, seven of the nine assets are located on land adjacent to substations, making transmission connection an easier process. All nine assets will utilise 2.7-hour batteries, with the full portfolio having a total capacity of 612MW/1.652GWh. A statement from the financial consortium says that this is believed to enhance operational efficiencies.
Energy-Storage.news notes that £180 million is unlikely to cover the entire capex needed for 1.65GWh of BESS, so the remainder will presumably come from other financing sources.
Quinbrook closes ‘UK’s largest’ project financing for Cleve Hill NSIP
Quinbrook Infrastructure Partners has announced the close of debt financing for the Cleve Hill solar and battery storage project.
Classed as a nationally significant infrastructure project (NSIP) due to the scale of the solar plant, Cleve Hill comprises 373MW solar and a 150MW BESS. Based in Kent, the power plant is expected to commence operations this year.
Quinbrook says the project financing is the largest ever closed for a solar + storage development in the UK. Financing was arranged in two tranches, with term loans for the solar PV completed in August 2024 and for the BESS facility in March this year.
The finance, a £218.5 million term loan and a £20 million VAT facility, is provided by Lloyds and NatWest.
Harmony Energy agrees to £190.8 million takeover offer
BESS investment fund Harmony Energy Income Trust has received an offer for a potential buyout.
Harmony Energy Income Trust (HEIT) has received an offer from Foresight Group LLP for the latter to potentially acquire the entire share capital of HEIT for 84.0p per share, making up a total of £190.8 million. HEIT has an operational BESS portfolio of 395.4MW/790.8MWh across the UK.
A firm offer still needs to be made by Foresight, which HEIT shareholders would need to vote on, but HEIT management is minded to recommend they vote in favour, assuming the firm offer is made on the financial terms outlined.
This represents a 29% premium on the closing share price of 65.2p on 14 March 2025, and a 76% premium on the share price in May 2024, on the last business day immediately before news of a potential asset sale was announced.
However, the value of the offer is still lower than HEIT’s most recently disclosed Net Asset Value (NAV). As Energy-Storage.news wrote late last year, the disparity between the two is the reason HEIT had to launch a sale in the first place (Premium access).
In a results announcement released in late February 2025, covering the year up to 31 October 2024, HEIT’s Net Asset Value (NAV) was established at £201.05 million, or 88.52 pence per ordinary share.
Although not technically a project financing, the update brings the total financing for BESS across the four announcements to roughly £1 billion.
See the original versions of the articles on Solar Power Portal below:
Zenobē lands financing for 400MW Eccles project
Constantine Energy Storage secures £180 million financing for BESS portfolio
Quinbrook closes ‘UK’s largest’ project financing for Cleve Hill NSIP
Harmony Energy Income Trust agrees to £190.8 million takeover offer
