European Battery Index

What a 1 MW / 2 MWh battery could have earned on the day-ahead market on 28 October 2026: Italy Sicily 688 € at the top, Norway NO5 9 € at the bottom, median across 38 zones 259 €.

Updated daily · last delivery day 28 October 2026 · 127 days of history

Revenue by zone

Theoretical day-ahead arbitrage revenue per day for a 1 MW / 2 MWh battery, in euros. The last column scales the 30-day average to a year (k€ per MW), a rough comparison point, not a forecast.

30-day average by zone

How the index is calculated

For every bidding zone and every delivery day we solve a linear optimisation: when should a 1 MW / 2 MWh battery charge and discharge to earn the most from that day's day-ahead prices? The model uses 88 % round-trip efficiency, allows at most one full cycle per day, starts and may end the day empty, and works in the auction's own resolution (15 minutes where the market clears in quarter-hours, otherwise hourly).

Prices are assumed known in advance, so the result is an upper bound for day-ahead arbitrage. It ignores network fees, degradation costs, forecast errors and all other revenue streams (balancing capacity, aFRR/mFRR energy, intraday). Use it to compare zones and days, not to value a specific project.

Frequently asked questions

Is this what a real battery earns?

No. It is the theoretical maximum from day-ahead arbitrage alone, with prices known in advance. Real assets earn less from day-ahead (forecast errors, fees, degradation limits) but often more in total, because they also sell balancing services (FCR, aFRR, mFRR) and trade intraday, which this index leaves out.

Why 1 MW / 2 MWh and one cycle a day?

A two-hour battery with one full cycle a day is a common design for new grid-scale projects and keeps the numbers comparable across zones. The index is a relative signal: where and when price spreads pay, not a project valuation.

Where does the data come from?

Day-ahead auction results published on the ENTSO-E Transparency Platform (SDAC), the same prices on our European electricity prices page. The optimisation is our own.