25 May 2026 · 5 min read
Dynamic versus fixed contract: which fits a battery?
By Stefan Douw · Maker of Stekkerkompas
A fixed contract is predictable. A dynamic contract follows hourly prices, which enables battery arbitrage but also passes price spikes through to you.
With a battery
Only with a battery and the self-plus-arbitrage strategy does the upside of dynamic really show. Without a battery it is mostly a bet on when you happen to use power.
The pitfall
If you charge an EV on dynamic prices, it already grabs the cheapest hours. That cuts your battery's extra arbitrage value sharply. Switch both on in the calculator and see the effect at once.
Run the numbers for your home
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