Steam quick check
A steam grid with gas boilers and an electric boiler can make steam from cheap power. Whether that pays depends on one number most plans ignore: the annual peak, because the grid bills the highest quarter hour of the year for twelve months. This check runs a whole year of German day-ahead prices through three ways of running the boiler and shows what the pressure band of your grid is worth on top.
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Result for 2025
Loading 2025 prices.
| Strategy | Steam from power, MWh | Added peak, MW | Saving a year |
|---|
What the band is worth
One week, hour by hour
- Power cheaper than gas
- Site load without the boiler
- Electric boiler under the plan
- Load under the simple rule
- Load limit of the plan
Tomorrow on prices published today
- Power cheaper than gas
- Site load without the boiler
- Electric boiler under the plan
- Load under the simple rule
- Load limit of the plan
How it works and what it leaves out
The baseline makes all steam with gas. The simple rule runs the electric boiler whenever power is cheaper than gas per MWh of steam. The plan runs it in the same cheap hours but keeps the site below a load limit, and it picks the limit with the lowest total cost, capacity charge included. The band is the pressure swing the plant allows on its steam grid. Inside it the grid stores heat, so the boiler can fill the band in a cheap hour and let it drain in a dear one, and the pool can sell the same swing as reserve: switch the boiler on for a quarter hour when the grid operator asks. Day-ahead prices are known the day before, so a plan like this can run a day ahead.
The check leaves out separate steam storage, intraday trading, the flat-load grid-fee discount (§ 19 StromNEV), boiler start costs, and minimum run times. Power bought at a fixed price gains less.
Sources
- Day-ahead prices DE-LU 2025, hourly, from the Bundesnetzagentur on SMARD.de (CC BY 4.0). Average 89.3 €/MWh.
- Capacity charge from WSW Netz, preliminary price sheet 2026, high voltage, above 2,500 hours of use.
- Band: 1.5 MWh of stored heat per bar of pressure band, an assumption after Energies 14 (2021) 1533, where a band of about 2 bar on a chemical site held up to 10 MW for 15 minutes. Saturated steam near 16 bar moves about 3 °C per bar.
- Reserve price: 30,000 €/MW and year is an assumption. Batteries earned about 62,000 to 70,000 €/MW in the German aFRR capacity market in 2025 (EERA, 22 February 2026), and a load with a small band is available for fewer hours.
- Gas, CO2, grid fees and levies, efficiencies, and the sample site are assumptions.