If you’ve had solar panels fitted in the UK, you’ll know the panels themselves are only half the financial story. The other half is what happens to the electricity you generate but don’t use — and that’s governed by the Smart Export Guarantee, or SEG. Search “best SEG rates” and you’ll find a lot of noise: comparison tables that go stale within weeks, suppliers quietly changing terms, and a fair bit of confusion about what you’re actually entitled to. Here’s the straight version.
What the Smart Export Guarantee actually is
The SEG replaced the old Feed-in Tariff in January 2020. Under the FiT, the government set a fixed generation payment plus an export payment, both index-linked and guaranteed for 20 years. The SEG is a different animal entirely: it’s a licence obligation, not a subsidy. Any electricity supplier with more than 150,000 domestic customers has to offer at least one SEG export tariff, but — and this is the bit people miss — there is no minimum rate. The obligation is just to pay something above zero for every kWh you export.
In practice this means SEG rates vary enormously between suppliers, from token amounts of a penny or two per kWh right up to headline rates in the high teens. Some suppliers offer a genuinely competitive tariff to win your custom (particularly if you’re also buying your import electricity from them); others offer the bare legal minimum and hope you don’t notice. That gap is why shopping around for export specifically — not just switching your whole energy contract — is one of the most overlooked bits of solar ownership.
For context on where export payments sit against what you’re paying to import: typical UK grid electricity currently sits around 25p/kWh under the Ofgem price cap, so even a strong SEG rate is paid at a fraction of what you’d pay to buy the same unit back. That’s exactly why self-consumption — using what you generate rather than exporting it — remains the biggest lever in your solar economics, which is worth bearing in mind before you get too focused on chasing the top export number.
Fixed vs agile: two very different ways to get paid
When you’re comparing tariffs, you’ll run into two broad structures.
Fixed export tariffs pay a flat rate per kWh regardless of when you export, usually guaranteed for 12 months. These are simple, predictable, and easy to compare — you can put a number on your annual export income before you commit. Most homeowners with a standard south-facing array and no particular interest in managing their usage around price signals will find a good fixed tariff perfectly adequate.
Agile or half-hourly export tariffs track wholesale electricity prices in real time, updated in 30-minute blocks. On a cold, still, high-demand winter evening, agile export rates can spike well above anything a fixed tariff offers — sometimes dramatically so, because wholesale prices themselves spike. The catch is that your solar panels aren’t generating at 6pm in January; agile export tariffs pay their best rates precisely when you’re not producing. Where agile genuinely earns its keep is if you’re pairing solar with a home battery. A battery lets you store your midday generation and then either use it yourself or release it to the grid when the agile export price spikes — turning a flat, predictable panel-only export income into something considerably more dynamic. This is also where smart export tariffs start to blur into smart tariffs generally, with some suppliers offering combined import/export agile products that reward you for both timing your usage and timing your export.
The honest answer to “which is better” is: it depends on whether you have a battery and whether you’re willing to actively manage things. Panels-only, no battery, want simplicity — go fixed. Got a battery, or planning one, and don’t mind a bit of tariff-watching — agile can pay meaningfully more over a year. If you’re weighing that decision alongside the upfront numbers, our guide to solar battery storage costs lays out realistic 2026 installed pricing so you can work out whether the agile uplift justifies the extra kit.
Why MCS certification is non-negotiable
Every SEG tariff on the market requires your installation to be MCS certified — no exceptions. MCS (Microgeneration Certification Scheme) is the UK’s quality standard for renewable installations, and it’s the mechanism suppliers use to verify your system was designed and fitted properly, by a competent installer, using components that meet recognised standards.
This matters for two reasons beyond the obvious “you need it to get paid.” First, MCS certification is also what keeps you eligible for 0% VAT on the installation (residential solar and battery storage in Great Britain currently sits at 0% VAT until 31 March 2027, after which it’s scheduled to revert to 5%) — so a non-MCS installer isn’t just cutting you off from export income, they may be costing you on the install price too. Second, MCS paperwork is what most suppliers ask for as proof when you apply for a SEG tariff, alongside your MPAN (the meter point number for your electricity supply) and confirmation of your export meter type.
If you’re choosing an installer and haven’t started yet, checking their MCS registration is step one, not an afterthought. Installers such as ecoaim.co.uk in Central Scotland and Green Linc Renewables in Lincolnshire both work to MCS standards as a matter of course, which is worth confirming with any installer you’re getting quotes from, wherever in the country you are.
You don’t have to buy your electricity and sell it to the same company
This is the single most valuable thing to understand about the SEG, and it’s the bit that gets buried. Your export tariff and your import tariff are completely separate contracts. You are under no obligation to export to the same supplier you buy your electricity from. If your current supplier’s SEG rate is poor — and plenty are — you can switch your export arrangement to a different supplier entirely while keeping your import contract exactly as it is.
The process is straightforward: apply to the new supplier for their SEG tariff, provide your MPAN, MCS certificate, and evidence of your export meter reading (most modern smart meters handle this automatically), and once approved, that supplier starts paying you for exports going forward. Your energy bill for the power you buy carries on being issued by whoever you’re with for imports. Two separate relationships, two separate switches, and no requirement that they match.
A few practical points worth knowing before you switch export-only:
- Check for exit fees or minimum terms on your current export tariff — most are free to leave, but always worth a five-minute check.
- Smart meter required. SEG payments are based on actual half-hourly export data in most cases, which needs a working smart meter (SMETS2, or SMETS1 that’s been enrolled onto the DCC network). If your smart meter has gone “dumb” — a known issue on some older installs — sort that first, or you may be stuck on deemed export estimates instead of your real generation figures.
- Rates change. Fixed SEG tariffs are typically only guaranteed for 12 months, so treat this as an annual job, the same way you’d shop around on car insurance. Set a reminder for renewal time and check the market again rather than rolling onto whatever your supplier defaults you to.
- Read the fine print on “up to” headline rates. Some of the highest-advertised SEG rates only apply if you’re also on that supplier’s specific import tariff, or are capped at a certain export volume. Compare the actual rate you’ll get, not the marketing number.
What good export income actually looks like
To put rough numbers on it: a well-oriented UK home solar array typically yields around 850 kWh per kWp per year (rising towards 1,050+ kWh/kWp in the sunniest parts of the south). A typical 4kW residential system might therefore generate somewhere in the region of 3,400–3,600 kWh annually, though how much of that you export rather than use yourself depends heavily on your daytime usage patterns and whether you have a battery. Households without a battery commonly export 40–60% of their generation; with a battery smoothing out evening usage, that export share drops, but each exported kWh may be worth more if you’re on an agile tariff timed to spike windows. At the stronger end of the current SEG market (roughly 12–20p/kWh depending on supplier and tariff), export income on an unbattered system can realistically run into a few hundred pounds a year — a genuine dent in payback time, even if it was never designed to be the main event. For a fuller picture of how export income fits into overall payback, our solar panel payback period piece walks through the maths alongside install costs.
It’s also worth remembering the SEG sits within a wider set of 2026 support measures that often get confused with each other. The Boiler Upgrade Scheme’s £7,500 grant is for air source heat pumps and does not apply to solar PV. ECO4 and the Warm Homes scheme are means-tested support for low-income, low-EPC households rather than universal solar grants. And if you’re on a farm rather than a house, England’s solar grant support runs through the Improving Farm Productivity grant at roughly 25% of eligible cost — not the old FETF 40% figure that still circulates online. None of these overlap with the SEG, which is purely about what you’re paid for the electricity you export, but it’s easy to see why people conflate them.
Getting it set up properly
If you’re new to solar and want the SEG side handled correctly from day one, that starts with the installer conversation — make sure MCS certification, export meter configuration and G98/G99 grid notification are all part of the quote, not an add-on you have to chase later. Installers like FLD Electrical in South Wales and ElectriFusion Solutions in South Yorkshire handle this as standard groundwork on residential installs, and it’s a reasonable question to put to any installer you’re comparing quotes from regardless of region.
If you’re running a business rather than a household, the SEG landscape is broadly similar in mechanics but the numbers scale differently — worth a look at solarpanelgrantsforbusinesses.co.uk if commercial export and grant stacking is relevant to your situation, or commercialsolarfinance.co.uk if you’re weighing finance options against export income as part of the payback case.
The practical takeaway: don’t let your SEG tariff be an afterthought bolted onto your installer’s default supplier relationship. Confirm your system is MCS certified, treat export as a switchable service independent of your import contract, decide honestly whether a fixed or agile tariff suits how you use (and store) your power, and put a calendar reminder in for renewal time. None of it is complicated once you know the separation exists — it’s just rarely explained clearly at the point of installation.