One of Europe’s biggest battery energy storage projects just took a major step forward in Scotland—and it’s happening at the site of a former coal mine.
Independent renewables firm RES has officially signed on to manage the Coalburn battery energy storage system (BESS), a 500MW/1GWh installation that could shift how the country handles its surging wind power supply.
From Fossil Past to Storage Future
The Coalburn site isn’t your average clean energy location.
It’s set on the remnants of a coal mining operation in Lanarkshire, a place that once powered the nation with fossil fuels. Fast-forward to 2025, and it’s now making headlines for a totally different reason: high-capacity battery storage.
RES, one of the most experienced players in the sector, will handle asset management. That means overseeing everything from performance analytics to maintenance coordination and operational compliance.
Two phases are planned. The first—Coalburn 1—is already underway and is expected online by the end of this year. Coalburn 2 is targeting a 2027 completion date.
Why This Battery Matters
So, what makes this one stand out?
For starters, size. Coalburn 1 alone is 500MW with two hours of storage duration, giving it 1GWh of usable capacity. That makes it one of the largest standalone battery projects on the continent.
It’s not just about energy volume. It’s about location. Scotland’s power grid is bursting with wind on good days, but much of that energy ends up curtailed—meaning turbines are paid to stop generating because there’s nowhere for the electricity to go.
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That’s where BESS steps in. With grid-scale batteries, power can be absorbed during peak generation and released when demand returns or when the wind stops blowing.
The Big Players Behind It
The development of Coalburn BESS is being spearheaded by two major players: Copenhagen Infrastructure Partners (CIP) and Alcemi. RES will manage it, but ownership is about to shift too.
When Coalburn 1 is commissioned later this year, CIP will sell half of its stake to alternatives investment giant AXA IM Alts. The commercial operations, meanwhile, will be handled by SSE Energy Markets, which will optimize both phases of the project once online.
Here’s a quick breakdown of who’s doing what:
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RES: Asset management
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CIP: Project developer (original owner)
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Alcemi: Co-developer, site planning
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AXA IM Alts: Will take 50% ownership post-commissioning
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SSE Energy Markets: Optimisation and energy trading
Big money, high stakes, and long timelines—pretty standard mix for infrastructure at this level.
Coalburn Isn’t Alone
CIP is clearly betting big on Scottish storage.
In addition to Coalburn, the firm is developing Devilla, another 500MW BESS project near Fife. That would bring CIP’s total Scottish storage footprint to 1GW—enough to hold back significant wind surges and help the grid ride out volatility.
That’s good news for Scotland, where some areas see turbines stopped on windy days because there’s just too much power. Transmission capacity hasn’t kept pace with the renewables boom, and battery storage is the quickest way to fix the mismatch.
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Zonal Pricing Debate: A Sigh of Relief
Last week, investors across the UK energy sector exhaled—loudly.
There had been growing speculation that the UK Government might introduce zonal pricing for electricity markets. In simple terms, this would have meant lower prices for electricity generated in areas like Scotland, where there’s a glut of wind power.
Sounds good for consumers, sure. But for investors? Not so much.
Lower prices in generation-heavy zones would’ve hurt revenues for new projects, making Scotland a riskier bet for developers. Coalburn could’ve ended up much less profitable.
Instead, the UK will stick with a national pricing model and push forward with:
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Reformed Transmission Network Use of System (TNUoS) charges
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Strategic Spatial Energy Planning (SSEP) by the National Energy System Operator (NESO)
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Expanded support for grid-scale battery storage
This approach doesn’t lower local energy bills right away, but it does give developers like CIP and Alcemi more confidence to keep building in Scotland.
Batteries, Not Politics, Will Keep the Lights On
Malcolm Patterson, CIP’s UK commercial director, wasn’t rattled by the pricing debate.
Speaking to Energy Storage News before the government announcement, Patterson made it clear that while zonal pricing reform might shift the financial calculus for generation, it doesn’t do much to the value proposition of batteries.
Why? Because storage earns money from arbitrage—charging during low-price hours and discharging when prices spike. That’s a different game from generating electricity.
Even in a future with zonal price differences, batteries will still play a key role in balancing the grid, keeping frequency stable, and—most critically—avoiding waste when renewables flood the system.
A quick reality check.
Global Numbers, Local Impact
For RES, the Coalburn contract is more than a Scottish milestone—it’s part of a much bigger map.
The company now manages over 43GW of energy assets worldwide, spread across more than 1,300 sites. That includes wind, solar, hydrogen, and storage, giving RES one of the largest third-party clean energy portfolios on the planet.
Here’s a snapshot of RES’ global reach:
| Asset Type | Capacity Managed (Approx.) |
|---|---|
| Wind | 22GW |
| Solar | 13GW |
| Battery Storage | 6GW |
| Green Hydrogen | 2GW |
| Total | 43GW |
