What the Smart Export Guarantee is
The Smart Export Guarantee (SEG) is a Great Britain scheme, overseen by Ofgem, that requires certain electricity suppliers to offer a tariff for electricity exported by small scale low carbon generators. Licensed suppliers above a customer threshold must take part as SEG licensees, and other suppliers may choose to. You are paid for each kWh you export, measured by a meter.
The SEG replaced the export element of the Feed-in Tariff for new installations. It is not a subsidy paid by the government: the supplier sets its own price, which must always be above zero.
Who can get it
According to Ofgem's SEG guidance, to be eligible an installation must:
- Be in Great Britain (England, Scotland or Wales).
- Use an eligible technology: solar PV, wind, hydro, anaerobic digestion or micro combined heat and power.
- Have a total installed capacity of no more than 5 MW (50 kW for micro combined heat and power).
- Meet the accreditation and metering requirements described below.
Businesses, farms, schools, charities and public bodies can all receive SEG payments, as can community energy groups.
Accreditation: MCS up to 50 kW, ROO-FIT above
How you prove your system is eligible depends on its size:
- Up to 50 kW: the system must be installed by an MCS certified installer using MCS certified equipment. You give the SEG licensee your MCS certificate.
- Over 50 kW and up to 5 MW: MCS does not apply, so the system needs ROO-FIT accreditation through Ofgem before a supplier will pay SEG.
Many commercial systems are larger than 50 kW, so it is worth asking your installer early who will handle the ROO-FIT application. Ofgem's information for generators explains the process.
Export meter
SEG payments are based on metered export, not estimates. Your site needs a meter that records export, ideally one the supplier can read remotely, with its own export reference number. Larger commercial sites often already have half-hourly metering, but the export meter point may still need registering. Ask your installer and supplier to confirm the arrangements before commissioning.
Rates and terms vary
Each SEG licensee sets its own tariff, so rates differ widely. Some offer a fixed price for a set period, some a variable rate, and some time of use rates that pay more at certain hours. Points to compare:
- The rate per kWh and how long it is fixed for.
- Whether you must also buy your import supply from the same company. You can choose a different SEG licensee from your current supplier.
- How meter readings are taken and how often you are paid.
- Whether the offer is available for systems of your size.
Ofgem publishes the list of SEG licensees. Larger exporters may also be able to negotiate an export arrangement outside the SEG, often called an export PPA. Compare any such offer against SEG rates.
How much difference the tariff makes
Using the illustrative example, a 100 kWp system exporting 18,000 kWh a year would earn:
| Export rate | Annual export income |
|---|---|
| 3p per kWh | £540 |
| 5p per kWh | £900 |
| 10p per kWh | £1,800 |
| 15p per kWh | £2,700 |
Even at 15p, export income is small beside the £17,280 saved by using 72,000 kWh on site at 24p. Shopping around for the best tariff is worthwhile, but it rarely changes whether a project makes sense.
SEG and the old Feed-in Tariff
The Feed-in Tariff closed to new applicants in 2019. Existing Feed-in Tariff installations keep their payments under the terms they signed up to. If you are adding a new system to a site that already has a Feed-in Tariff installation, talk to your Feed-in Tariff licensee and your installer about metering before you commission, so that the two systems are measured correctly.
Selling the site or changing supplier
A SEG contract is between the generator and the SEG licensee. If you sell the building, the new owner will normally need to arrange their own SEG contract. You can usually move to a different SEG licensee, subject to the notice terms in your contract. Keep your MCS certificate or ROO-FIT accreditation details safe, because a new licensee will ask for them.
Northern Ireland
The SEG does not apply in Northern Ireland. Some suppliers there have offered their own export payments, but terms and availability vary, and grid connections go through NIE Networks. Our page on Northern Ireland support covers the differences.
Why export income is a small part of the case
In our illustrative 100 kWp example, 80% of generation is used on site at 24p per kWh, saving about £17,280 a year. The 20% exported at an illustrative 5p per kWh earns about £900. Export income is under 5% of the total benefit.
Every unit you use on site is worth your full unit rate, while every unit exported earns only the export tariff, so a business case built mostly on export is usually weak. See our solar payback guide for how self-consumption, unit rates and export rates each move payback.
This shapes system design:
- Size the system around your daytime demand, using energy data analysis of your half-hourly data.
- Consider a battery if you have evening demand or low weekend use. See battery storage for business.
- If the local network has little export capacity, an export limitation scheme under G100 may let you install a larger system while capping export. Our page on G99 and DNO applications explains the process.
When export matters more
For some organisations, export is a bigger share of the picture. Schools and colleges generate the most in summer, when the building is often empty during the holidays. Churches, sports clubs and other buildings used mainly in the evening or at weekends may also export much of their output. In those cases it is worth comparing SEG tariffs carefully, considering a battery, or sizing the system to the demand that does fall in daylight hours. Sites with steady weekday demand, such as factories and cold stores, usually export very little.
Tax on SEG income
For a business, SEG payments are generally part of your taxable income. Ask your accountant how to treat them in your accounts and tax return.
How to apply
- Have your system installed and commissioned, with the export meter in place.
- Get your MCS certificate (up to 50 kW) or ROO-FIT accreditation (over 50 kW).
- Compare SEG tariffs from licensees.
- Apply to your chosen licensee with your accreditation, meter details and proof you own or have the right to the installation.
A free survey shows how much you are likely to export and whether a smaller system or a battery would improve your return. Request a free survey to see the figures for your site.
Frequently asked questions
Can businesses get the Smart Export Guarantee?
Yes. Any eligible installation in Great Britain up to 5 MW can receive SEG payments, whether it belongs to a business, farm, school, charity or public body. Systems up to 50 kW need MCS certification. Larger systems need ROO-FIT accreditation through Ofgem. You also need a meter that records export, and you apply to the SEG licensee of your choice.
How much does the SEG pay?
It depends on the supplier. Each SEG licensee sets its own rate, which must be above zero, and offers vary from fixed to variable and time of use tariffs. Rates can change, so compare current offers on suppliers' websites using Ofgem's list of licensees. For most businesses, export income is a small part of the total saving.
Do I need MCS for a commercial system to get SEG?
Only if it is 50 kW or smaller. MCS covers solar PV up to 50 kW, and you give your MCS certificate to the SEG licensee. Systems over 50 kW, up to the SEG limit of 5 MW, need ROO-FIT accreditation through Ofgem instead. Ask your installer who will manage the application before work starts.
Is there a Smart Export Guarantee in Northern Ireland?
No. The SEG applies only in Great Britain. In Northern Ireland, export payments depend on what individual suppliers choose to offer, and connections are handled by NIE Networks. Check current options with suppliers before relying on export income in your business case.
Should I size my system to export more?
Usually not. Exported units earn far less than the unit rate you avoid paying when you use solar on site. Most commercial systems are sized around daytime demand, so that most generation is used on site. Export capacity on the local network can also be limited. Your survey will compare system sizes using your meter data.
Related pages
Solar paybackA worked payback example for a 100 kWp system, the factors that move the result most, the effect of tax relief, and a calculator to try your own figures.- G99 and DNO applicationsG98 versus G99, what goes into a DNO application, connection offers, export limitation under G100, reinforcement costs and how the survey checks your supply.
Battery storageWhen a commercial battery pays: storing surplus solar, time of use tariffs, peak shaving, sizing from half-hourly data, illustrative costs, safety and siting.- Northern IrelandCurrent solar support in Northern Ireland for businesses, community groups, public bodies and farms, plus export, rates, planning and official contacts.
- Energy data analysisHow half-hourly consumption data shapes solar sizing and payback: getting the data, profile classes, baseload, weekend and seasonal use, self-consumption and batteries.