Emaldo Market Review September: The Danish Ancillary Services Market

Issue 4 | October 2026, covering September 2026

Where we are now

In last month’s review we said we would look at whether the autumn demand season was beginning to deliver improved battery revenues in DK1 and DK2. September did not bring that improvement. Ancillary service prices in both zones stayed low and broadly stable, and benchmark revenues fell slightly for the second month in a row. This is why Grid Rewards payouts have not increased.

DK1: lower intraday and aFRR revenues

According to Clean Horizon, revenues in DK1 decreased in September, with the 2-hour index reaching 286 k€/MW/year, down 16.6% on the month. This was mainly driven by lower intraday prices and slightly lower aFRR capacity prices, partly offset by day-ahead spreads that were 22.7% higher. This followed August, when ancillary service prices in DK1 remained low, wholesale market volatility declined, and revenue for a 2-hour battery fell by 13.8%. Clean Horizon, September Clean Horizon, August

DK2: a short FFR spike, but lower overall

DK2 continues to earn more than DK1, but it also softened. The DK2 2-hour index reached 447 k€/MW/year in September, down 5.1% on the month. FFR prices rose sharply, but with low volume. In August, day-ahead volatility increased in DK2, but intraday revenue and FFR and mFRR prices fell slightly, and a 2-hour battery earned 8% less than in July. Clean Horizon, September Clean Horizon, August

Why this has not changed Grid Rewards

Two consecutive months of slightly lower revenues in both zones, alongside low ancillary service prices, leave no room for an increase in payouts. Short FFR price spikes in DK2 are welcome, but they involve small volumes and do not lift earnings across a residential portfolio.

Battery supply is also still growing. Denmark registered 191 MW of battery capacity between Q3 2025 and Q2 2026, across 4,479 installations, with residential batteries increasing from 546 installations to 1,403. Clean Horizon notes that ancillary service markets have a fixed size set by system needs, so as the Nordic fleet grew they saturated and battery revenues shifted towards energy trading. ESS News

That shift is clearest for longer-duration batteries. For a 4-hour battery in DK1, Clean Horizon found that ancillary services earned 322 k€/MW of the 436 k€/MW total in 2025, while up to July 2026 they earned 155 k€/MW of 461 k€/MW annualised, with intraday contributing 242 k€/MW. Residential batteries are shorter-duration assets and rely more on capacity markets, so they have not seen the same benefit. Clean Horizon

What is coming next

The longer-term picture remains positive. Clean Horizon found that the average daily spread rose in 2026, reaching 149 €/MWh in DK2 and 142 €/MWh in DK1, among the highest in the Nordics, helped by the fact that DK1, DK2 and SE4 are well interconnected with Germany and benefit from that link in terms of volatility. Clean Horizon

Demand for electricity is also growing. Danish electricity consumption rose from 34.2 TWh in 2019 to a record of just over 40.4 TWh in 2025, the first time it has exceeded 40 TWh. Dansk Industri

One timeline has moved. Energinet will join MARI, the European mFRR platform, together with the other Nordic TSOs in autumn 2027, later than the early 2027 date previously expected. Energinet

What this means for your earnings

Grid Rewards payouts in Denmark have not increased. Revenues in both DK1 and DK2 eased slightly in August and September, and ancillary service prices remain low as more batteries compete for the same services.

Wider price spreads, growing electricity demand and new market connections give real reasons for optimism over the longer term. Emaldo will keep working with our partners to access the widest possible range of markets, evolve as the market changes, and grow what your battery earns. Your battery also continues to save you money on your electricity bills every day, regardless of ancillary service prices.

Next month

In our next review we will cover price movements across FCR, aFRR, mFRR and intraday markets in DK1 and DK2 for October, the first full month of the heating season.