The Smart Export Guarantee (SEG) is a UK scheme that makes suppliers pay you for solar power you send to the grid. Energy Saving Trust says you typically get around 12p per kWh. Each supplier sets its own rate, so the best offer can differ a lot from the worst.
How the scheme works
Ofgem runs the scheme but does not set the price. Licensed suppliers with at least 150,000 domestic customers must offer at least one SEG tariff. Smaller suppliers can offer one if they wish, although few have to. Whatever the rate, it has to be above zero.
To qualify, your system must be in Great Britain. Solar PV up to 50kW needs an MCS certificate or equivalent. You also need a meter that records export, because the supplier pays only for what it can measure.
The scheme does not cover Northern Ireland. Energy Saving Trust notes that export tariffs there depend on the supplier. If you live in Belfast, ask your supplier what it offers before you rely on any figure here.
What tariffs pay at the time of writing
Rates change often, so treat these as a snapshot from 10 October 2026. They show the spread you may meet.
| Tariff | Rate | Who can join |
|---|---|---|
| Outgoing Octopus | 12p per kWh | Octopus customers with a smart meter |
| British Gas Export Premium | 12p per kWh | British Gas electricity customers, systems up to 15kW |
| E.ON Next Export Exclusive | 13p per kWh, 12-month fixed | E.ON Next import customers, systems up to 15kW |
| E.ON Next Flex Export | 6p per kWh, variable | New and existing customers |
The gap between 6p and 13p is large. On 1,000 kWh exported, it is £60 against £130 in a year. However, many of the higher rates need you to buy your import power from the same supplier. Compare the whole package, not only the export line.
Why self-use still beats export
A kWh you use at home saves you the import price. Currently, the Ofgem price cap electricity unit rate is 26.32p per kWh for October to December 2026. A kWh you export earns around 12p. Therefore a self-used unit is worth over twice an exported one.
Take a worked example. Say a 4kWp system exports 1,500 kWh in a year. At 12p that pays £180.
If you used those same 1,500 kWh at home, you would save about £394.80 at 26.32p. The rates will move. Still, the gap is likely to stay wide.
This is why a solar battery comes up so often. It stores midday surplus for the evening, so you export less and import less. Our check on whether a solar battery is worth it runs the numbers on cost against saving. For many homes the answer depends on how much you export now.
Estimating how much you will export
Export depends on how much your panels make and how much you use while the sun shines. Start with output. PVGIS gives about 1,122 kWh per kWp a year for Plymouth. That is 4,488 kWh from a 4kWp south facing system at 35 degrees.
Our page on solar output in Plymouth shows the monthly split. Exeter is a little lower at 1,052 kWh per kWp, or about 4,208 kWh from 4kWp. London is lower again at 1,019, or about 4,076 kWh.
You can see how those compare on the pages for solar output in Exeter and solar output in London. All three figures come from PVGIS v5.3. The wider solar panel installation service page explains how an MCS install and its output estimate work.
Next, think about your day. A household that is out from 8am to 6pm uses little at midday, so it exports more. Someone working from home uses more as the panels make it. Roof direction and tilt also shift when output peaks, as we explain in the best tilt angle for UK panels.
Winter and summer
Output swings through the year, and so does export. In London, PVGIS shows about 40.7 kWh per kWp in January and 123.2 in July. Most export comes in the long summer days. Our look at solar panel output in winter shows why winter export is small.
Because of this, the export rate matters less than it first seems. Most of your saving comes from the power you use. A good SEG tariff is a bonus on top, not the reason to buy.
Reading the small print
Check the contract length before you sign up. A 12-month fixed rate gives certainty, while a variable rate can fall without much notice. Look at who can join, too, since several of the best rates need you to be an import customer.
Ask whether the tariff pays for all exported units or only some. Some tariffs also need a smart meter that records half-hourly export. For example, Outgoing Octopus lists that as a condition. A tariff that looks generous may not suit your meter.
Planning and paperwork
The scheme needs an MCS certified install, so check your installer first. The planning rules for your roof matter too. Our guide to solar panels and planning permission covers the position in England, Scotland, Wales and Northern Ireland.
Once your system is live, your installer can give you the documents your supplier asks for. Then you apply to the supplier of your choice. You can switch SEG tariff later, as with any other energy deal.
How many panels you will need
Export also depends on system size. A bigger array makes more surplus in summer, but it also costs more. Our post on how many solar panels you need walks through sizing from your own usage. Meanwhile, the calculator gives a sensible starting point.
Next steps
Solar Yield is an independent estimator. It passes enquiries to MCS-certified installers, and it does not install anything itself. Use the solar yield calculator to estimate your output, then use the result to judge how much you might export. When you are ready to compare real offers, you can request quotes and ask each installer for its MIS 3002 output estimate.