Emaldo Market Review: The Swedish Ancillary Services Market

Issue 1 | June 2026

About this review

Every month we will publish a short review of the energy market that your battery operates in. We want you to understand what is happening in the market, why it matters, and what it means for your Grid Rewards earnings. This is the first of those reviews.

What your battery does

Your Emaldo battery works in two ways simultaneously. It works for your home, storing cheap electricity and using it when prices are higher, reducing your energy bills day to day. And it works for Sweden, providing the national grid with something called an ancillary service — the ability to respond in seconds when the grid needs to release or absorb power to stay in balance.

Grid operators pay for this service because a stable grid is essential for every home, school, hospital, and business in Sweden. The revenue from those payments is what funds your Grid Rewards. But your battery is also saving you real money on your electricity bills every single day — and that saving continues regardless of what happens in the ancillary services market.

A grid being transformed by wind and solar

Sweden's electricity grid has changed enormously over the past five years, and understanding that transformation is the key to understanding the ancillary services market.

The growth in renewable generation has been extraordinary. Sweden had 16.4 gigawatts of wind power capacity by the end of 2023, the fifth highest in Europe and the most per capita of any country in the world. Wind power generated 20.9% of all Swedish electricity in 2023, up from just 0.3% in the year 2000. Solar capacity has grown even faster, reaching 4.8 gigawatts in 2024, up from just 0.14 gigawatts in 2016. Taking all renewables together, Sweden's total installed renewable capacity grew from 22.7 gigawatts in 2010 to 40.6 gigawatts by 2023. Wind power generation alone is forecast to expand by a further 40% by 2028, with solar growing by 190%. Source: VaasansahkoBlog

This transformation creates both an opportunity and a challenge. Wind turbines only generate when the wind blows. Solar panels only work when the sun shines. On a still, cloudy winter afternoon, renewable output can fall sharply and quickly. On a breezy summer morning, the grid can receive far more electricity than anyone needs. The grid has to stay in balance at all times, and as more renewable generation connects, these swings become larger and more frequent.

Batteries are the most effective way of managing this. They absorb surplus power instantly and release it just as quickly when there is a shortfall. This role is not going to diminish — it is going to become more important as Sweden's renewable capacity continues to grow.

How the ancillary services market works

The ancillary services market is made up of several distinct products, each paying battery operators for a different type of grid support. Understanding these products helps explain the price movements of the past three years.

The fastest-acting product is Fast Frequency Response (FFR), which requires a battery to react within fractions of a second. Next comes Frequency Containment Reserve (FCR), which responds within 30 seconds and comes in two forms: FCR-N for normal grid conditions and FCR-D for disturbances. Beyond these sit the Frequency Restoration Reserves — aFRR (automatic, within minutes) and mFRR (manual, within 15 minutes). Each product is procured by Svenska Kraftnät, the Swedish transmission system operator, and prices are set by supply and demand in each market.

What has happened to prices

The story of ancillary service prices in Sweden over the past three years is, at its core, a story of supply growing far faster than demand.

FFR was the first product to experience significant price falls. FFR prices dropped significantly in 2023. With annual average procurement volumes between just 2 to 4 megawatts, it does not take much to saturate the market. As battery operators recognised the high revenues available, they rushed to pre-qualify their assets for FFR. Supply quickly overwhelmed the small amount of capacity the grid needed, and prices collapsed. Source: Moneysavingexpert

The same pattern then played out in FCR-D, the reserve product activated during grid disturbances. Between early 2023 and late 2024, prequalified FCR-D capacity surged from under 10 megawatts to around 600 megawatts. However, as total demand for FCR-D remains below 550 megawatts and is not expected to rise, the market became saturated in 2024, leading to a significant drop in FCR-D market prices. Source: cleanhorizon

The downward price trend aligns directly with the increase in flexible capacity offered to the market. In the first quarter of 2022, only 77 megawatts of capacity was contracted. By the fourth quarter of 2024, this figure had risen to 470 megawatts. January 2025 saw a record low average price for FCR at just €6.02 per megawatt per day. Source: Sympower

The Clean Horizon Battery Storage Index (cleanhorizon.com/battery-index) tracks annualised revenue for battery storage assets across European markets and captures the overall picture clearly. The Swedish index peaked at around 1,700 kEUR per MW per year in July 2023. By early 2026, the same measure had fallen to between 100 and 200 kEUR per MW per year — a reduction of over 90% from the peak. The chart below shows this journey in full.

This is not a uniquely Swedish story. The same trajectory has played out in Finland, Denmark, and other European markets where battery deployment has accelerated rapidly. Sweden's battery energy storage capacity expanded from just 80 megawatts to over 610 megawatts in 2024 alone, marking one of the most dynamic periods of growth any European nation has undergone. The grid simply could not absorb that volume of new capacity at previous price levels, and prices adjusted accordingly. Source: Hubspotusercontent-eu1

Where the market is heading

With FCR-D no longer the highly lucrative option it once was, attention has shifted to mFRR, the tertiary reserve market. At the beginning of 2025, just 120 megawatts of storage was pre-qualified for mFRR. By the end of the first quarter of 2025, this number had jumped to nearly 600 megawatts. The same supply-driven price pressure that affected FFR and FCR-D is therefore beginning to emerge in mFRR as well. Source: Moneysavingexpert

However, there are structural reasons to believe the market will continue to develop. Recent reforms in mFRR — including automatic activation and the adoption of a 15-minute market interval — are expected to increase price volatility in that market, representing a promising opportunity for energy storage operators. Svenska Kraftnät is also expected to increase the volumes procured for aFRR and mFRR by 2030, which should help support price levels as demand for balancing grows. Source: Moneysavingexpert

Sweden is aiming for at least 50 gigawatts of renewable capacity by 2030. The European Union has made a legally binding commitment to climate neutrality by 2050, requiring near-total decarbonisation of the power grid and a significant acceleration in the addition of renewable capacity. More renewable generation means more intermittency, and more intermittency means a growing structural need for exactly what batteries do. The direction of travel for battery storage over the medium and long term remains strongly positive, even as the market works through its current period of adjustment.

What this means for your earnings

As ancillary service prices have fallen across the Swedish market, the revenue available to fund Grid Rewards has reduced in turn. Customers are therefore likely to notice lower Grid Rewards earnings in the coming months, reflecting the current state of the market.

It is worth remembering that your battery continues to create real financial value for your home every day through energy cost savings — buying electricity cheaply, avoiding peak prices, and making the most of any solar generation. In a market where electricity prices remain elevated, that day-to-day saving is a consistent and meaningful benefit that sits alongside whatever the ancillary services market delivers.

We will continue to work hard to access the best available markets and maximise what your battery can earn on your behalf as the Swedish market evolves.

Guaranteed Grid Rewards plan Sweden

We have made the difficult decision to temporarily pause new sign-ups to the Guarantee Grid Rewards plan in Sweden. As our Swedish market review explains, ancillary service prices in Sweden have been highly volatile over the past two years, falling significantly from their peak in 2023. When prices move as quickly and unpredictably as they have, it becomes extremely difficult to forecast what the market will generate over a three-year period with enough confidence to offer a fixed guaranteed payment. Rather than set a guarantee at a level that may not be sustainable, we feel it is more important to be straightforward with you about what the market can currently support. We want to be clear that this is a temporary decision and one we are not comfortable with. The Guarantee plan is an important part of what makes Emaldo different, and we are genuinely committed to bringing it back for new customers in Sweden as soon as market conditions give us the stability and predictability we need to do so responsibly. We will keep you updated as the market evolves. Existing Guarantee plan customers are not affected by this change and will continue to receive their guaranteed payments as normal. The Flexible Grid Rewards plan remains fully available, and your battery will continue earning on your behalf in the meantime. 

Next month

In our next review we will cover the latest price movements across FCR, aFRR, and mFRR in Sweden for the month of June, and what they mean for the months ahead.

Price data in this review is sourced from the Clean Horizon Battery Storage Index (cleanhorizon.com/battery-index) and from Svenska Kraftnät's published ancillary services market data.