Solar panels make electricity whether you are in or out. What you do not use goes back out to the grid, and your electricity supplier pays you for it.
How much they pay varies from 4p a unit to 20p a unit — for the same panels on the same roof. Which one you get is not decided by the equipment, or the weather, or your postcode. It is decided by who bills you for electricity, and by who fitted the system. Both of those get chosen months before anybody mentions being paid for anything.
Here is the shape of it, from one supplier's published rates, checked on 29 August 2026.
The same roof, three prices
OVO publishes three rates for buying back the electricity you don't use (the scheme's official name is the Smart Export Guarantee, or SEG):
| Tariff | Rate | Condition |
|---|---|---|
| SEG | 4p/kWh | Open to anyone, whoever supplies your electricity |
| SEG Beyond Exclusive | 12p/kWh | You buy your electricity from OVO |
| SEG Install Exclusive | up to 20p/kWh | You buy your electricity from OVO and OVO installed the system |
Source: ovoenergy.com/smart-export-guarantee, read 29 August 2026. The same page states 15p/kWh where OVO installs solar panels only and all other criteria are met, and puts a capacity condition on the exclusive rates — under 30kW installed, against a much higher ceiling on the open tariff.
That is a five-fold spread on identical exported electricity. Nothing about the panels changed. Nothing about the roof, the postcode or the weather changed. The only variables are who bills you for the electricity you import, and who screwed the brackets to the rafters.
Octopus operates the same idea in a milder form. Its published export tariffs are 12p/kWh flat on Outgoing Octopus, or 16p/kWh between 4pm and 7pm and 9p/kWh the rest of the day on Prime Outgoing, fixed for twelve months (octopus.energy/smart/outgoing, read 29 August 2026) — and its export tariffs pair only with certain import tariffs.
Why suppliers are allowed to do this
Because the scheme was designed that way. Ofgem's own description of the Smart Export Guarantee is blunt about it:
"SEG Licensees determine the rate, contract length and other terms which SEG Generators will receive. SEG tariff rates must always be above zero."
That is the entire pricing rule. Above zero. Everything above that floor is a commercial decision by the supplier, which is why "the SEG rate" is not a thing that exists — there are only individual suppliers' rates, and they differ by a factor of five.
Ofgem's advice follows from it: generators "should shop around to see which tariff is best for their individual circumstances".
When you actually make this decision, without knowing it
Not when you apply for the tariff. Earlier, and twice.
When you choose an installer. An install-exclusive rate is only available if that supplier's own installation arm did the work. Once someone else has fitted your system, that tier is closed to you permanently, and no amount of switching afterwards reopens it. This is the decision people make on price and availability, months before the word "export" comes up.
When you choose who supplies your electricity. The middle tier — 12p rather than 4p, on OVO's published rates — needs only that you buy your import from the same company. That one is reversible: you can switch. But it means the right question when comparing import tariffs is not just the unit rate, it is what does this supplier pay me for export, and does that offer depend on being their customer?
What the gap is worth, and how to work out your own
We are not going to give you an annual figure, because it depends on how much you export, which depends on your system, your consumption and your occupancy. What we can give you is the arithmetic:
(units exported per year) × (rate A − rate B) = the value of the decision.
On OVO's published rates the gap between the open tariff and the install-exclusive one is 16p a unit. A household exporting 2,000 units a year would see £320 a year turn on it; one exporting 1,000 would see £160. Put whichever number is yours into the same sum. Then compare that against the price differences between the installers you are choosing among, over the same number of years, and see which decision is actually the big one.
Two things that will move the answer, and which we are not going to pretend away: you export only what you do not use, so a battery that raises self-consumption lowers export volume; and every rate on this page can change. Fixed-term export tariffs are fixed for their term, variable ones are not.
What to ask before you sign anything
- What export tariff will I be on, at what rate, and is that rate conditional on who supplies my import? Get the answer in writing before you choose an installer, not after.
- Does this installer's parent company offer an install-exclusive export rate? If so, it is part of the price comparison.
- Is the export rate fixed or variable, and for how long?
- Is MCS certification of the installer and the products in place? Suppliers ask for MCS certification before paying a SEG tariff. That is a separate thing from the ENA type test register we publish — the ENA register covers the equipment's grid-connection testing and nothing about who fitted it.
- Am I comparing the export rate against the import rate from the same supplier? A generous export tariff attached to an expensive import tariff can easily be the worse deal overall.
What we hold, and what we do not
We publish the ENA type test register, which tells you whether the inverter in a system has been type tested for connection to the grid. It tells you nothing about tariffs, and nothing about MCS.
We do not publish comparative export rates across suppliers, and this page deliberately quotes only two — the two whose current rates we read directly from their own pages on the date shown. Energy tariff pages cache badly and change constantly; an out-of-date p/kWh figure produces a wrong savings number with our name on it, which is the exact failure we criticise in others. Ofgem publishes the list of SEG licensees annually, and it is the authority on who is obliged to offer a tariff at all.
[NEEDS VERIFICATION: current export rates from the other SEG licensees — E.ON Next, EDF, British Gas, ScottishPower, So Energy, Utilita and the voluntary licensees. We are gathering these with a dated fetch per supplier and will publish the comparison when every row has one.]
Rates on this page checked 29 August 2026. Check them yourself before you rely on them.
Related reading: a battery earns from the tariff spread, not from the sun, and what the ENA register actually covers.