Most households with rooftop solar use only part of what their panels generate. The surplus flows into the grid — and under the Smart Export Guarantee (SEG), that surplus is supposed to earn money rather than disappear for free. Yet many system owners never claim it, simply because the paperwork and the jargon get in the way. This guide walks through what the scheme is, who qualifies, and what to check before signing an export contract.
What the Smart Export Guarantee is
The SEG came into force on 1 January 2020, replacing the export payments that the old Feed-in Tariff scheme offered to new installations. It is set out in the Smart Export Guarantee Order 2019 and enforced through licence conditions overseen by the energy regulator, Ofgem. The principle is deliberately simple: licensed electricity suppliers above a certain size must offer at least one tariff that pays small-scale generators for each unit of low-carbon electricity they export to the grid.
Crucially, the regulator does not prescribe the rate, the contract length or the payment frequency. Suppliers set those terms themselves, subject to one hard rule: the export rate must be above zero at all times. Beyond that floor, rates and conditions vary widely between providers, which is why comparing contracts matters more than most households expect.
Who must offer an export tariff
The obligation attaches to supplier size. Any licensed electricity supplier with at least 150,000 domestic customers as of 31 December is a mandatory SEG licensee for the following scheme year, which runs from 1 April to 31 March. Those suppliers cannot opt out. Smaller suppliers are free to participate voluntarily, and many do. Every licensed supplier must declare its status to the regulator annually.
Eligibility: the checklist that decides your application
Before a supplier will pay you, the installation itself has to qualify. The requirements are set centrally, and the same framework applies whether you have four panels on a semi-detached roof or a small commercial array.
| Requirement | What it means in practice |
|---|---|
| Eligible technology | Solar, wind, hydro, anaerobic digestion or micro-CHP, with a total capacity up to 5 MW. |
| Certified installation | For solar, wind and micro-CHP up to 50 kW, an MCS certificate (or proof of an equivalent standard) is expected. |
| Export metering | A meter that records exports at half-hourly intervals — a modern smart meter usually qualifies. |
| Export MPAN | A dedicated export supply point reference created for the metering of what you send to the grid. |
| No overlapping payments | You cannot receive Feed-in Tariff export payments and SEG payments for the same exports. |
Two of these trip people up most often. First, the MCS certificate: it is issued at commissioning, so if you lose it or the installer never provided it, chase a replacement before applying — retrofitting the paperwork is far slower than keeping it from day one. Second, the export MPAN: the network operator creates it, and it can take a few weeks, so it is usually the longest step between applying and getting paid.
Key takeaways
- Export payments are a legal entitlement, not a favour — large suppliers cannot refuse to offer at least one tariff.
- Keep the MCS certificate from the day of commissioning; it is the passport to any export contract.
- Your export provider and your electricity supplier do not have to be the same company.
- Batteries change the economics: stored solar used at home is usually worth more than the same unit exported.
Self-consumption versus export: why the maths leans inward
Every unit of solar you use yourself displaces a unit you would otherwise buy at the full retail price. The same unit exported earns only the export rate, which is necessarily lower than what you pay to import. That gap is the entire reason self-consumption sits at the heart of system design — and it is where battery storage enters.
A home battery shifts surplus generation from midday, when the household is often out, to the evening, when demand peaks. Each shifted unit converts a low-value export into an avoided full-price import. Storage also unlocks time-of-use export products, which pay more for electricity delivered during evening peaks. One caveat matters: where a battery can also charge from the grid, suppliers are not obliged to pay for that grid-charged electricity when it is exported later. Some pay anyway, some ask for extra metering, some estimate the eligible share — so ask the question before you sign, not after.
For importers and distributors of solar and storage equipment, the practical takeaway is that export-readiness is a product feature. Kits should ship with documentation that helps the end customer complete certification and metering steps, because in the UK market a system that cannot be registered is a system that cannot earn.
Frequently asked questions
Do I need an MCS certificate to claim the Smart Export Guarantee?
For solar, wind and micro-CHP installations up to 50 kW, the energy regulator expects an MCS certificate or proof of an equivalent certification standard. Larger installations up to 5 MW must still have the installation certified, but the installer itself does not have to be certified.
Do I have to buy my electricity from the same supplier that pays my export tariff?
No. Your export tariff provider does not need to be the same company as your electricity supplier. However, some of the highest export rates are reserved for customers who also buy their electricity from the same company, so it is worth comparing the whole package before signing.
Does a smart meter count as an export meter for SEG payments?
In most cases yes. The requirement is a meter that records exports at half-hourly intervals and is associated with a dedicated export MPAN. A modern smart meter can usually do this, but you should confirm suitability with your chosen tariff provider before applying.
Will a supplier pay for electricity exported from my battery?
They must pay for electricity generated by eligible sources such as solar, but they do not have to pay for export from a battery that was charged from the grid. Some suppliers choose to pay anyway, others ask for additional metering or estimate the eligible share — always ask before signing a contract.
Sources & further reading
- Ofgem — Smart Export Guarantee (SEG) guidance and licensee obligations — ofgem.gov.uk
- UK Government — Smart Export Guarantee policy — gov.uk
- UK legislation portal — Smart Export Guarantee Order 2019 — legislation.gov.uk
- MCS — certification standard for small-scale renewable installations — mcscertified.com
中文摘要
英国 Smart Export Guarantee（SEG）自 2020 年 1 月起强制大型供电企业（上年底住宅客户数≥15 万）为小型低碳发电用户提供余电上网电价，费率只须大于零、由企业自定。申领需满足：技术类型与容量合规（≤5MW；≤50kW 太阳能须 MCS 证书或等效证明）、可半小时记录的出口电表与出口 MPAN、且未重复领取旧 Feed-in Tariff 出口补贴。供电企业与出口电价提供方可以不是同一家。自用电比余电上网更划算，蓄电池把白天余电挪到晚高峰使用价值更高；但电网充电的电池放电是否计费由企业自定，签约前须问清。