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Export & SEG · · 8 min read

Smart Export Guarantee 2026 | Best Commercial SEG Tariffs

Best commercial SEG tariffs 2026 — Octopus Outgoing, EDF Variable, British Gas rates compared. How to switch and maximise export income.

Tom Acheson — Senior Energy Modeller

The Smart Export Guarantee is the legal mechanism requiring Ofgem-licensed electricity suppliers (with over 150,000 customers) to pay UK businesses for surplus solar exported to the grid. SEG replaced the Feed-in Tariff in 2020 and now governs how every commercial PV system above 5kWp gets paid for export. This piece sets out the current 2026 tariff landscape and how to pick the right SEG product for a commercial site.

SEG basics

SEG is not a grant. It is a recurring revenue mechanism. The mechanics:

  • You generate solar electricity
  • Some is consumed on-site (self-consumption)
  • The surplus is exported to the grid
  • Your SEG-licensed supplier pays you per kWh exported, typically monthly or quarterly
  • Payments are based on half-hourly export readings from your meter

To qualify for SEG you need an MCS-certified solar system (or other low-carbon source: wind, micro-CHP, AD, hydro), a smart meter capable of half-hourly export readings, and an SEG tariff agreement with a licensed supplier. You can keep import with one supplier and export with another — they don’t have to be the same company.

System size cap: 5MW for solar (50kW for micro-CHP). Above 5MW you sit outside SEG and need a separate Power Purchase Agreement for the export contract.

Why SEG matters for commercial solar

For most commercial solar projects, self-consumption is between 65% and 92% of generation. The remaining 8–35% is exported. On a typical 500 kWp commercial site generating 475,000 kWh/year, that’s 38,000 to 166,000 kWh of annual export.

At a flat 6p/kWh SEG tariff, that’s £2,280 to £9,960/year of export revenue. At a top-of-market flat tariff of around 12p/kWh, it’s £4,560 to £19,920. At a dynamic tariff that captures peak-time export at 30p+/kWh, it can exceed £30,000/year on the same project. The choice of SEG product is therefore material to project IRR — typically worth 0.5–1.5 years of payback period on most sites.

The 2026 tariff landscape

We track SEG tariffs across all UK suppliers offering commercial SEG products. The picture as verified in July 2026:

Fixed tariffs (paid same rate regardless of when export happens):

  • EDF Energy Export Variable: 12.5p/kWh
  • Octopus Energy Outgoing Fixed: 12p/kWh — cut from 15p on 1 March 2026, so it no longer leads the fixed tier and now sits level with the 12p cluster
  • E.ON Next Export Variable: 12.0p/kWh
  • Scottish Power Smart Export: 11.5p/kWh
  • British Gas Export & Earn Plus: 6.4p/kWh
  • Ovo Energy Export: 4.0p/kWh — among the lowest

Variable / time-of-use tariffs (paid different rates by time of day):

  • EDF Energy Export Variable Daily: 14p/kWh peak, 8p/kWh off-peak
  • Octopus Energy Outgoing Lite: 8p/kWh flat with demand response top-ups
  • Scottish Power Smart Export Saver: variable 8–18p/kWh seasonal

Dynamic tariffs (paid wholesale market rate per half-hour):

  • Octopus Energy Outgoing Agile: tracks half-hourly wholesale electricity prices. Average pay-out 2025/26 was 12.4p/kWh, with peaks above 30p/kWh and floors below 0p/kWh on rare days. Best for sites with battery storage that can shift export into peak windows.
  • Octopus Tracker (commercial variant): less common but available for sites with predictable export profiles.

Dynamic tariffs are the highest-revenue option for sites with battery storage. Without storage, dynamic tariffs are typically marginally better than fixed tariffs but carry more revenue volatility.

Picking the right SEG tariff

The decision depends on three factors:

Battery storage. If you have battery storage, dynamic tariffs (Octopus Outgoing Agile primarily) materially outperform fixed tariffs because the battery can shift export into half-hours where wholesale prices are high. Without storage, fixed tariffs are usually better — your export profile is determined by solar generation and on-site consumption, not by your choice of when to export.

Export profile. Sites with summer-skewed export profiles (most commercial sites) benefit slightly from dynamic tariffs because summer peak prices are higher than winter. Sites with winter-skewed export profiles (less common, mostly retail and hospitality) get less benefit.

Risk tolerance. Fixed tariffs lock in revenue. Dynamic tariffs vary. For financial models that need to underwrite specific year-1 revenue, fixed tariffs are easier. For sites where the operator is comfortable with monthly revenue variation, dynamic tariffs typically pay more.

For most commercial sites without battery storage, the strongest mainstream fixed options in 2026 cluster tightly rather than having a clear leader: EDF Export Variable (12.5p/kWh), Octopus Outgoing Fixed (12p/kWh since the 1 March 2026 cut from 15p) and E.ON Next Export Variable (12.0p/kWh). Each carries its own import condition, so read the terms rather than the headline rate. For sites with battery storage, Octopus Outgoing Agile is materially better.

Switching your SEG tariff

You can hold import with one supplier and export with another. The switching mechanics:

  1. Confirm your MCS certificate is in your name with the correct system size.
  2. Choose the SEG tariff and apply with the supplier.
  3. The supplier requests your half-hourly export readings from your import supplier (this is a standard data flow — should take 7 to 14 days).
  4. Once data is flowing, your SEG payments start.
  5. Existing import contract continues unaffected.

Most switches complete within 14 to 28 days. There is no lock-in on most SEG tariffs — you can switch again if a better tariff appears.

SEG and PPAs

If your solar PV is funded under a PPA, the export situation is different. The PPA funder owns the asset and the export rights. Any SEG revenue accrues to them, not to you. This is reflected in the PPA tariff — funders price PPAs assuming a base SEG revenue stream, and the PPA tariff is lower as a result.

Some PPAs explicitly allow the host to claim export revenue. Read the contract. The relevant clause is typically called “Export Energy” or “Surplus Energy” and defines who has the rights to revenue from grid-exported electricity.

SEG and grid services beyond export

A growing number of commercial solar sites with battery storage are participating in grid services markets — primarily the Balancing Mechanism, Dynamic Frequency Response, and Demand Flexibility Service (the National Grid ESO winter scheme). These markets pay separately from SEG and can be additive.

Aggregators like Flexitricity, GridBeyond, Limejump, Octopus KrakenFlex and Habitat Energy bundle multiple commercial sites into virtual power plants and trade them into these markets. Typical revenue from grid services for a site with 250 kWh of battery storage is £8,000 to £25,000/year on top of SEG.

For sites with battery storage above 500 kWh, the grid services revenue often exceeds the SEG revenue. The two are complementary — SEG covers solar export, grid services cover battery flexibility — and modelling both in the financial case is essential.

What to model in your financial case

When we build financial models for clients, the export revenue line includes:

  • SEG revenue at the chosen tariff applied to the modelled export profile
  • Grid services revenue if battery storage is included and the site has the demand profile to participate
  • DUoS / capacity charge avoidance where the battery + solar reduce peak demand charges
  • Inflation assumptions for SEG (typically tracked CPI on long-term contracts)

For 25-year financial models, the export revenue line typically represents 10–22% of total project revenue — not dominant, but material. Models that ignore it understate IRR by 1.5–3 percentage points.

Forward outlook

Three trends affecting SEG economics into 2026 and beyond:

Wholesale electricity prices stabilising. The 2022–24 spike has unwound. Wholesale prices in 2026 average £75–£95/MWh against £180/MWh peak in 2022. This caps fixed SEG tariffs at the suppliers’ margin against wholesale, and the squeeze is already visible: Octopus raised Outgoing Fixed from 12p to 15p in early 2025, then cut it back to 12p on 1 March 2026. We don’t expect fixed tariffs above 18p/kWh in the foreseeable future.

Dynamic tariff growth. More suppliers are launching dynamic export products. Octopus has been the leader; EDF and Scottish Power are following. Competition should improve dynamic SEG returns over the next 18 months.

Smart meter rollout maturing. Half-hourly export data is now near-universal for commercial connections. This unlocks more sophisticated SEG products including site-specific dynamic tariffs.

Market reform. The 2024 Review of Electricity Market Arrangements (REMA) consultation explored locational pricing and other reforms that could affect long-term SEG economics. Concrete changes are unlikely before 2027.

How to review your SEG tariff

If you have an existing solar system on an old SEG tariff (signed pre-2023), review it. Tariffs moved materially upward between 2023 and 2025, and although the market’s headline fixed rate has since come back down — Octopus cut Outgoing Fixed from 15p to 12p on 1 March 2026 — the best fixed tariffs still pay roughly double the 5–7p/kWh many businesses are stuck on, so those older contracts remain uncompetitive.

A tariff review takes 30 minutes. Send us your current SEG contract and 12 months of export data; we’ll model the alternatives and tell you whether switching is worth it.

The fastest route is the free funding review form — note “tariff review” in the message and we’ll handle it as a separate workstream.

Funding by asset class

The allowance depends on the asset, and most pages on this topic get it the wrong way round. Solar PV is special-rate expenditure (HMRC Capital Allowances Manual CA22335), so the 100% year-one route is the Annual Investment Allowance — Full Expensing is a main-rate measure and does not reach it. Battery storage, EV charging and heat pumps are main-rate plant, so Full Expensing genuinely does apply to those.

Free funding review

Find out which 2026 schemes your site actually qualifies for

What you get, within one working day
  • 1. A short written funding note naming every scheme your site qualifies for in 2026 — and the ones it does not.
  • 2. Indicative system size and a capex band for your roof.
  • 3. Year-one tax treatment per asset in £ — solar is special-rate expenditure, so the route is the Annual Investment Allowance; battery storage and heat pumps are main-rate plant, where Full Expensing does apply. Most pages get this the wrong way round.
  • 4. Projected SEG export revenue at current rates.
  • 5. Any red-flag eligibility or DNO issues we can see up front.

Covers solar PV, battery storage, EV charging and commercial heat pumps — separately or as one bundled project. If your project is a heat pump or a battery rather than a roof, say so in the message box and the note is written against that asset instead.

What we will not do
  • · We do not pass your details to multiple installers.
  • · We do not run a lead auction, and we never ask for your phone number.
  • · No marketing lists, no unsolicited calls.
  • · We are an independent funding consultancy — not an installer, and we take no installer commission.

Five questions. They are the eligibility test itself — scheme eligibility in 2026 turns on sector, tenure, site size and spend, so we cannot shortlist anything without them.

We reply from funding@commercialsolargrants.co.uk. No phone number required, ever.