Smart Export Guarantee Calculator
Calculate your estimated Smart Export Guarantee (SEG) payments and export earnings from UK solar PV systems, battery storage, and wind installations based on supplier tariffs.
Smart Export Guarantee Calculator
How to Use the Smart Export Guarantee Calculator
Estimating your solar export income from your solar PV system or battery storage installation under the UK Smart Export Guarantee scheme is straightforward. Follow these steps to calculate your payments:
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1Enter exported electricity. Input the amount of surplus electricity exported to the grid in kilowatt-hours (kWh). You can obtain this value from your smart meter or dedicated export meter readings.
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2Enter SEG tariff rate. Input the export rate offered by your energy supplier in pence per kilowatt-hour (p/kWh). SEG tariffs typically range from 5p to 30p/kWh depending on your supplier and contract.
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3Select payment period. Choose the corresponding time period for the exported energy value you entered (Monthly, Quarterly, or Annually) to calculate period payments and annual equivalents.
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4Choose VAT option. Select whether to include VAT in the output. For domestic export tariffs, VAT is generally not added, but standard businesses may apply 5% VAT depending on eligibility.
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5Calculate earnings. Click the "Calculate SEG Earnings" button to view your estimated payments, export metrics, and total annual equivalent revenue.
How to Calculate Smart Export Guarantee Payments
Under Ofgem regulations, the Smart Export Guarantee (SEG) payments are determined by multiplying your metered export energy by the tariff rate agreed with your energy supplier. The calculations are based on actual, measured kWh exported to the grid, rather than estimated generation.
SEG Mathematical Formulas
To compute your export revenue, use the following three formulas:
Formula 1 — Convert Tariff to Pounds:
Formula 2 — Calculate SEG Payment:
Formula 3 — Calculate Annual Equivalent:
(Where the period multiplier is 12 for monthly readings, 4 for quarterly readings, and 1 for annual readings)
Step-by-Step UK Export Worked Example
Let's look at a typical UK home solar PV system export example:
- Solar PV Export: 350 kWh per month
- SEG Tariff Rate: 15 p/kWh
- VAT Option: No
Step 1 — Convert the Tariff Rate to Pounds
Tariff (£/kWh) = 15 p/kWh ÷ 100 = £0.15/kWh
Step 2 — Calculate Monthly SEG Payment
Payment = 350 kWh × £0.15/kWh = £52.50 / month
Step 3 — Calculate Annual Income Equivalent
Annual Income = £52.50 × 12 months = £630.00 / year
Walkthrough Final Verified Results
- → Monthly Export: 350 kWh
- → Tariff Rate: £0.15 per kWh
- → Monthly Payment: £52.50
- → Annual Export Revenue: £630.00
To qualify for the SEG scheme in the United Kingdom, your installation must be MCS certified or equivalent and connected in compliance with Engineering Recommendations G98 or G99 depending on system capacity. You must also ensure your electrical install conforms to BS 7671 standards.
Smart Export Guarantee Payment Chart
This reference chart displays the estimated SEG payment values (in £) for various levels of exported electricity (kWh) across typical UK export tariff rates (5 p/kWh to 30 p/kWh).
| Exported Energy (kWh) | 5 p/kWh | 10 p/kWh | 15 p/kWh | 20 p/kWh | 30 p/kWh |
|---|---|---|---|---|---|
| 100 kWh | £5.00 | £10.00 | £15.00 | £20.00 | £30.00 |
| 250 kWh | £12.50 | £25.00 | £37.50 | £50.00 | £75.00 |
| 500 kWh | £25.00 | £50.00 | £75.00 | £100.00 | £150.00 |
| 1,000 kWh | £50.00 | £100.00 | £150.00 | £200.00 | £300.00 |
| 2,000 kWh | £100.00 | £200.00 | £300.00 | £400.00 | £600.00 |
Note: SEG tariffs vary by supplier and contract. All values are calculated excluding VAT.
Smart Export Guarantee Calculator Frequently Asked Questions
The Smart Export Guarantee (SEG) is a UK government-backed scheme introduced in January 2020. It requires licensed energy suppliers to pay solar PV owners and other renewable generators for the low-carbon electricity they export back to the National Grid. It applies to systems up to 5MW in capacity.
SEG payments are calculated by multiplying the quantity of exported electricity (recorded in kWh by an export meter or smart meter) by the supplier's export tariff rate (in p/kWh). Optional VAT (usually 5% for domestic or standard commercial exports depending on status) may also be added if applicable.
In the UK, SEG export tariffs vary widely. Standard tariffs generally range from 5p to 15p per kWh, but some energy suppliers offer premium export rates between 15p and 30p per kWh, particularly when paired with a matching import tariff or home battery system.
Yes, battery storage systems can qualify for the Smart Export Guarantee. This is known as "brown electricity" export, where stored energy is fed back into the grid. However, some suppliers require proof that the battery is charged from a certified renewable source, like a solar PV array.
Most major UK energy suppliers require an MCS (Microgeneration Certification Scheme) certificate or equivalent to approve a SEG application. While some suppliers accept alternative proof of compliance with standards like BS 7671, G98, or G99, MCS certification remains the standard route.
Payment frequency depends entirely on the energy supplier and the export contract terms. Typically, SEG payments are made quarterly or annually, though some suppliers offer monthly credits or direct bank transfers based on half-hourly smart meter readings.
