Self-consumption measures the share of your generation used at home. Self-sufficiency measures the share of your demand supplied by your own generation.
Use the right denominator
Imagine a home generating 4,000 kWh, using 1,600 kWh of that directly, and consuming 5,000 kWh overall. Its direct self-consumption is 40%; its direct self-sufficiency is 32%. These are illustrative numbers, not typical results.
Keep the seasons in view
A yearly balance does not mean you can disconnect from the grid. Surplus on a bright summer day does not automatically cover a cold winter evening. Storage usually shifts energy over much shorter periods than the seasons.
Ask what improves the outcome
Flexible demand can use generation as it arrives, while a battery may move some use to later. Neither creates extra solar energy. Compare the cost and practicality of each option, and check how losses and exported electricity are treated in any calculation.
Sources & further reading
- Médiateur national de l’énergie — L’autoconsommation
- Verbraucherzentrale — Energiemanagement zu Hause