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Smart Solar Power Estimator
Calculate how much you can earn by selling surplus solar electricity back to the grid through the Smart Export Guarantee (SEG). Compare rates from Octopus Energy, British Gas, OVO, and EDF.
📊 Est. Annual Export: 2,056 kWh/year
Generated: 3,738 kWh/yr × 55% exported
Annual SEG Income — Octopus Energy
2,056 kWh × 25.0p = £514/year
25-year export earnings: £12,816
| Supplier | SEG Rate | Type | Smart Meter Required | Notes |
|---|---|---|---|---|
| Octopus Energy | Up to 25p/kWh | Variable (time-of-use) | Yes | Intelligent Flux — best rates at peak demand times |
| British Gas | 15p/kWh | Fixed | Yes | Stable, predictable income. No bundling required. |
| OVO Energy | 12p/kWh | Fixed | Yes | Simple flat rate, no time-of-use complexity |
| EDF Energy | 5.6p/kWh | Variable | Yes | Lower rate but may suit EDF import customers |
| E.ON Next | 15p/kWh | Fixed | Yes | Competitive fixed rate |
| Scottish Power | 15p/kWh | Fixed | Yes | Standard competitive rate |
*Rates as of June 2025. Always verify current rates directly with the supplier before switching.
The Smart Export Guarantee (SEG) is a UK government-backed scheme that requires energy suppliers with 150,000+ domestic customers to pay solar panel owners for electricity exported to the National Grid. It launched on 1 January 2020, replacing the Feed-in Tariff (FIT) which closed to new applicants in April 2019.
Unlike the FIT, the government does not set a minimum SEG rate — instead, suppliers set their own competitive rates, which means the rates vary significantly (from 4p to 25p/kWh in 2025). This creates an opportunity to shop around and maximise your income.
The SEG calculation is simple: SEG Income = Annual Export kWh × SEG Rate (£/kWh). If your 4kWp system exports 1,870 kWh/year and your supplier pays 15p/kWh, you earn £280.50/year.
The Smart Export Guarantee (SEG) is a UK government scheme introduced in January 2020 that requires larger energy suppliers (with 150,000+ domestic customers) to offer export tariffs to eligible small-scale low-carbon generators including solar panel owners. Unlike the old Feed-in Tariff (FIT), the SEG rate is set by individual suppliers, not the government, meaning you should shop around for the best rate.
SEG earnings depend on your export rate and how much electricity you export. In 2025, typical rates range from 4p to 25p per kWh. A 4kWp system exporting ~1,870 kWh/year (55% of generation) would earn: £75/year at 4p, £280/year at 15p, or £468/year at 25p. Choosing the right supplier makes a huge difference.
As of 2025, Octopus Energy offers some of the highest SEG rates through their Intelligent Flux tariff (variable, peaking at 20p–25p during high-demand periods). British Gas offers 15p/kWh fixed. OVO Energy offers 12p/kWh fixed. EDF offers ~5.6p/kWh variable. Always check current rates on the supplier's website as these change periodically.
Yes — you must have a smart meter (or equivalent export metering) to receive SEG payments. Your smart meter measures your actual export in kWh, which is used to calculate your SEG income. If you don't have a smart meter, some suppliers use a deemed export rate (typically 50% of generation), but this is less accurate and often less financially optimal.
Yes — FIT customers can switch their export portion to a SEG tariff while keeping their FIT generation payments. Since FIT deemed export was typically only 50% of generation at low rates, switching to SEG with a smart meter can significantly increase export earnings for high-exporting systems. Check with your current supplier before switching.