Hybrid site powering 7,500 homes

The park was built by HSB Södermanland together with Alstra Energy, and is owned not by a single company but by around 70 HSB housing cooperatives and HSB entities. Member cooperatives buy shares in the park and receive locally produced, renewable electricity at a favourable rate, a cornerstone of HSB's work on green member value and reduced climate impact.

When it was switched on in 2020, with 50,000 panels producing around 18,000 MWh per year, about as much as 7,500 apartments use, it was described as Sweden's largest solar park. The Swedish solar market has grown quickly since then, but the park remains one of the country's landmark large-scale solar sites. Sheep graze between the rows of panels, keeping the vegetation down.

From solar park to hybrid site

What makes the site especially interesting today is that it is a hybrid: a 4 MW battery storage has been co-located with the solar park, and Qurrent optimizes the two together as a single asset. By scheduling solar and battery jointly, rather than as two separate assets, the site can shift energy in time, firm up its output and stack value across up to five ancillary service markets at once, far more than either resource could reach on its own.

Both assets are active across Sweden's ancillary service markets. The battery delivers FCR-D, FCR-N and mFRR, while the solar park also contributes down-regulation capacity, so the whole site works as one flexible resource behind a single grid connection. Spreading revenue across several markets also smooths earnings, since a fall in the price of any single market is cushioned by the others.

The results are tangible: over the last twelve months the site contributed upwards of 45,000 MWh of sold capacity to the ancillary services markets. A park that was built purely for solar production now maximizes its value by also generating revenue from grid services.

Key data

Location

Strängnäs

Site type

Hybrid (solar park + BESS)

Solar capacity

10.5 MW

Battery storage

4 MW

Solar panels

50,000

BRP

Jämtkraft

EPC / developer

Alstra Energy

Owners

~70 HSB cooperatives & companies

Battery markets

FCR-D UpFCR-D DownFCR-NmFRR UpmFRR Down

Solar markets

FCR-D DownmFRR Down

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