Learn · 9 May 2026
Solar export tariff vs self-consumption: which wins for battery owners?
A practical breakdown of when to sell solar to the grid and when to store it for yourself, for UK homes with a battery and an export tariff.
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If you have solar, a battery, and an export tariff, every kilowatt-hour your panels produce sits at a fork: store it for later, or sell it to the grid right now? The answer changes through the day and through the year.
The trade-off in plain English
Self-consumption pays the avoided import rate (what you would have paid to buy that unit later). Export pays the export rate (what the grid is paying you right now).
When the export rate beats the avoided import rate, sell. When it does not, store.
Why the answer changes through the day
Avoided import rates on Agile move every half hour. So does the export rate on dynamic export tariffs. The "right" choice in the middle of the day might flip by the afternoon.
The battery’s state of charge matters too — a near-full battery has nowhere to put extra solar, so exporting becomes the only option.
How a planner thinks about it
A good planner forecasts both your generation and the price curves for the day, then lays out a sequence of charge, hold, discharge and export decisions that maximise the day’s economics.
The detail that catches people out: discharging the battery through expensive import periods is usually worth more than exporting it, even on a good export tariff. Cheap-to-store, expensive-to-replace.
Common questions
- Is it worth getting an export tariff if I have a battery?
- Almost always yes. Even if most of your solar is self-consumed, an export tariff turns surplus that the battery cannot hold into cash rather than dumping it for free.
- Should I empty the battery to the grid during export peaks?
- Sometimes. If the export rate is well above the avoided import rate for the rest of the day, exporting the battery makes money. The key word is "above" — model it before assuming.
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