Self-consumption is the number that decides whether solar pays

Two different prices for the same electron

When you use a solar kilowatt-hour yourself, you avoid buying one at the retail rate. When you export it, you usually receive a much lower export rate.

If retail is €0.28/kWh and export is €0.08/kWh, self-consumed energy is worth 3.5× exported energy.

Typical ranges (starting points only)

Without a battery, many homes land around 25–35% self-consumption of PV generation. With a typical home battery, 60–75% is a common planning band — still not a fact for your household.

How to raise it without hardware

Shift immersion heaters, EV charging, dishwashers and laundry into sunny hours. Match array size to daytime loads rather than annual kWh alone. Oversizing for 100% offset can simply mean more cheap exports.

Model the effect in the solar payback and battery ROI tools.