Guide · Smart Export Guarantee for business
The Smart Export Guarantee, for businesses.
Every commercial system we install is built to be SEG-eligible, but export is the consolation prize, not the business case. A unit you use on site is worth roughly three times a unit you sell back. Here is how the scheme works, what you need to qualify, and how we design around it.
The basics
What the scheme actually is.
The Smart Export Guarantee is an obligation placed on licensed electricity suppliers, introduced in January 2020 after the Feed-in Tariff closed to new applicants. Larger licensed suppliers, the SEG licensees, must offer at least one tariff that pays eligible small-scale generators for the electricity they send back to the grid. Ofgem administers the scheme; the suppliers set their own rates and compete on them.
The eligibility ceiling is 5MW, which in commercial terms is enormous. The 154 kWp rooftop array we designed for Harris Parts Ltd would need to be scaled up more than thirty times before the cap became relevant. If you are a business with a roof, the question is never whether you qualify by size. It is whether the certification and the metering are in place.
The SEG covers small-scale low-carbon generation up to 5MW. Virtually every commercial rooftop in the country sits well inside that cap.
It is an obligation on licensed electricity suppliers — the larger ones must offer at least one export tariff. Government does not set the rate; suppliers compete on it.
Payment is on measured export, half hour by half hour. There is no deemed or estimated export figure the way the old Feed-in Tariff worked.
Eligibility
Two boxes to tick, and one application to make.
Qualifying for SEG payments comes down to certification and metering. The installation has to be certified, MCS for the vast majority of commercial rooftops, or an equivalent certification route on larger systems, and the supply has to be metered so that exported units can be measured half hour by half hour. There is no deemed export figure under the SEG the way there was under the old Feed-in Tariff: you are paid for what the meter records leaving the site.
Both are far easier to sort at handover than eighteen months later. We are MCS certified (NIC-600049) and RECC registered (00067281), and every commercial install leaves our hands with the certification pack the supplier will ask for.
Grid connection
G99, the DNO and export limitation.
Separately from the SEG, a commercial system needs a G99 connection application to your Distribution Network Operator before it exports. Across the West Midlands that is National Grid Electricity Distribution. The DNO assesses the local network and either accepts the proposed export, offers it with conditions, or grants a lower export limit than the array is capable of, occasionally zero.
Where a limit applies, an export limitation device enforces it. The system still generates and still powers the building exactly as designed; you simply cannot push the surplus onto a network that has no room for it. On tightly-loaded industrial estates this is increasingly the binding constraint on how large an array can be, and a further reason to design around what the site itself will consume.
We handle the G99 application as part of the project, alongside planning where it is needed, so the grid position is known before anyone commits to a system size.
The commercial reality
Export is the consolation prize.
This is the part most solar quotes get backwards. A unit of your own generation that you consume on site is worth the full delivered price you would otherwise have paid to import it, commodity, network charges and levies included. A unit you export is worth the SEG tariff alone. Across the market that makes a self-consumed unit worth roughly three times an exported one.
So the design question is never how many panels fit on the roof. It is how much of what this roof generates will the business actually use. That is why every proposal we write starts with half-hourly consumption data rather than a roof area: we model generation against your real load profile: shift patterns, weekend running, seasonal peaks, and size the array where the two curves overlap. Export then becomes what it should be, a bonus on genuinely surplus summer middays, rather than the assumption the payback quietly rests on.
Indicative, not a quote, the exact ratio depends on your import contract and the export tariff you sign. Your survey models both against real half-hourly data.
Three ways to turn export into self-consumption
Stores the midday surplus and releases it into the evening peak. A unit that would have been exported at the SEG rate is used at the import rate instead.
Battery storage for business →Workplace, fleet and visitor charging is daytime load — the exact hours your array generates hardest. Fleet charging is often the single biggest self-consumption gain on a site.
Commercial EV charging →Moving controllable plant — compressors, chillers, batch processes, immersion loads — into daylight hours costs nothing and lifts self-consumption immediately.
How payback is calculated →Commercial Battery Storage is the biggest single lever of the three. It is what lets a site with a short daytime load profile keep the value of a full summer's generation.
Process
How to apply, in order.
Keep the MCS certificate (or equivalent documentation), the commissioning paperwork and your MPAN together at handover. Reconstructing proof months later is the single most common reason a SEG application stalls.
Your supply needs half-hourly export metering, configured to record what leaves the site. Most commercial supplies are already half-hourly settled, so this is usually a configuration job rather than a new meter.
Compare SEG licensees on rate, tariff type, payment frequency and notice period. You are not obliged to stay with whoever bills your import — the export contract is separate.
Expect to supply the certificate, meter and MPAN details, proof of ownership, a site address and the account the payments go to. Some suppliers ask for photographs of the installation.
Check whether the rate is fixed for a term or tracks wholesale value, how often you are paid, and what happens if you later add a battery or change import supplier.
None of this is difficult, but it is sequential, and the paperwork step that trips businesses up is always the first one. Certification you can hand straight to a supplier is worth more than a marginally better export rate you cannot claim.
Questions
SEG, answered straight.
Anything else. Call and speak to a director, not a sales team.
Does my business need MCS certification to claim the Smart Export Guarantee?
In practice, yes. SEG licensees require the installation to be certified under MCS, or under an equivalent certification route for systems that fall outside the MCS scope. It is the certificate, not the hardware, that unlocks the export tariff — which is why we hand over the full MCS paperwork at commissioning. Green Tech Hub is MCS certified under NIC-600049.
Can I take my SEG tariff from a different supplier to the one that bills my electricity?
Yes. Export is a separate contract from import, so you can buy your electricity from one supplier and sell your surplus to another. It is worth checking both, because some suppliers reserve their best export rates for customers who also import from them, and the combined position is what matters — not the headline export rate on its own.
How much is the Smart Export Guarantee actually worth to a commercial site?
Far less than most quotes imply. Export earns you the SEG rate, whereas a unit used on site saves you the full delivered price you would otherwise pay to import it — roughly three times as much. On a well-designed commercial system with high daytime load, export is typically a modest share of the annual benefit and is best treated as upside rather than as the reason to invest.
Should a business choose a fixed or a variable SEG tariff?
A fixed tariff pays a set rate per unit exported, which is the number you can put in a board paper. A variable or agile tariff follows the wholesale value of power half hour by half hour, so it can pay considerably more at times of system stress and considerably less at sunny middays when everyone is exporting. We model paybacks on a conservative fixed assumption and treat anything a variable tariff earns above that as a bonus.
What happens if the DNO limits how much I am allowed to export?
On constrained parts of the network the DNO can grant an export limit below your array capacity, or in some cases zero export. An export limitation device then enforces it. The system still generates and still supplies the building normally — you simply cannot push surplus onto the network. It is another argument for sizing around on-site consumption, and we check the likely position with National Grid Electricity Distribution before finalising a design in the West Midlands.
Does adding a battery reduce my SEG income?
Usually yes, and that is the point. The battery captures surplus that would otherwise have been exported at the SEG rate and releases it later at the far higher value of avoided import. You lose a little export revenue and gain considerably more in bill savings. Where a battery is charged from the grid as well as from solar, check the tariff terms, as some SEG contracts treat exported grid-charged power differently.
Size it for what you use.
A free Business Energy Survey models your half-hourly consumption against a CAD-designed array, so you can see exactly how much you would self-consume, and how much would ever reach an export meter.
Related: commercial solar, payback, battery storage and EV charging.