Finland’s BESS Market: “Beyond the gold rush”?

Finland’s battery energy storage system market has developed at a remarkable speed. In only a few years, the country has moved from having very little grid-scale storage to seeing several 50–100 MW projects announced, built, or in development. What began as a reserve-market opportunity is now becoming a broader flexibility story, shaped by the growth of variable renewables, grid constraints, price volatility, new industrial electricity demand, and the search for more bankable revenue models.

To gain a deeper understanding of the mechanics of the Finnish market, we spoke with Matti Parpala, CEO and co-founder of Will & Must Oy. He explained how the Finnish BESS market has already passed through its first major phase.

“For some time, there was a huge opportunity to make outsized profits in the reserve markets,” he explains. “No wonder that BESS capacity has grown from nearly zero to around 1.5 GW in just a couple of years.”

That initial boom was driven by attractive reserve-market revenues. But as more batteries enter the market, the easy part of the opportunity is fading. “There will be a decent revenue stack available also in the future,” Parpala says, “but given market saturation, the biggest gold rush is clearly now behind, at least for now.”

Key takeaways

• Market maturation: The "gold rush" era of reserve markets is fading due to saturation. Success now requires complex revenue stacking across wholesale, balancing, and intraday markets.
• Shift to longer duration: Developers are moving from fast-response systems to longer-duration batteries to bypass grid connection limits (focusing on MWh over MW) and capture wholesale trading value.
• Hybrid complexity: Integrating batteries with renewables is valuable but often requires operational independence from the generation asset to remain commercially viable.
• Tolling as a de-risking tool: As merchant risk grows, tolling agreements are becoming essential for managing revenue and securing project financing.
• Data center demand: Data centers are a near-term driver for storage due to their inflexible power needs, whereas hydrogen remains speculative, relying on future policy and infrastructure.
• Domestic strengths: Finland's ecosystem is increasingly led by local firms in engineering and software, positioning them well to capture both domestic and international opportunities.