Self-Consumption explained
Self-consumption (or self-sufficiency) is the percentage of the solar electricity your system generates that you actually use within your home. It's one of the most important factors in maximising your solar savings.
Why it matters so much: electricity you use directly from your panels is worth the full retail price you'd otherwise pay (e.g. 24–28p/kWh in the UK). Electricity you export to the grid typically earns just 3–15p/kWh under the Smart Export Guarantee. Self-consumed power is therefore worth 2–5× more than exported power.
Typical self-consumption rates without a battery:
- Home occupied during the day: 40–60%
- Home unoccupied during work hours: 20–35%
- With a battery: 70–90%
Ways to increase self-consumption:
- Add battery storage to capture midday surplus for evening use
- Run high-demand appliances (washing machine, dishwasher, EV charging) during sunny hours
- Use smart home controls or diverter devices (e.g. iBoost) to heat water with surplus solar power
- Time your EV charging to coincide with peak solar generation
A smart diverter that sends surplus solar to your hot water cylinder can boost self-consumption by 10–15% at very low cost (typically £200–£350 installed).