Solar panel payback in southern England
The short answer
- 10.8 years to pay back a typical 4 kW south facing system in South and East England, earning about £556 a year
- About £7,097 left over 25 years after the £6,000 cost, or about £2,114 with a battery
- 13.2 years on an east or west roof, and 8.3 years on a 17.5p export rate
Updated 25 September 2026. Every figure on this page comes from our published model; see where our data comes from.
A typical 4 kW solar system in southern England costs about £6,000, generates about 3,780 kWh a year and brings in about £556 a year in bill savings and export payments, so it pays for itself in about 10.8 years. These are the solar calculator's figures for London, the South East, the South West and the East of England.
Payback by system size
About 10.8 years for 4 kW. Systems above 4 kW earn more over 25 years but pay back more slowly, because more of their output is exported at 12p rather than used at 26.32p.
| System | Installed cost | Generation a year | Saving and export a year | Payback | 25 years, after costs |
|---|---|---|---|---|---|
| 3 kW | £4,000 to £5,500 | 2,835 kWh | £434 | 10.9 years | £5,473 |
| 4 kW | £5,000 to £7,000 | 3,780 kWh | £556 | 10.8 years | £7,097 |
| 5 kW | £6,500 to £8,500 | 4,725 kWh | £675 | 11.1 years | £8,400 |
| 6 kW | £8,500 to £10,000 | 5,670 kWh | £794 | 11.6 years | £9,453 |
The data behind this table
South facing roof at a typical pitch, a household using 2,500 kWh a year (a bill of about £860) that is out for about half the day, no battery, 12p export on Outgoing Octopus. Payback uses the middle of each cost range; 0% VAT until 31 March 2027. The 25 year figure allows for the panels losing 0.5% of their output a year.
Roof direction
South is best, but east or west still pays back in about 13.2 years. A north facing roof makes much less and takes about 17.9 years.
| Roof faces | Generation a year | Saving and export a year | Payback |
|---|---|---|---|
| South | 3,780 kWh | £556 | 10.8 years |
| South-east | 3,591 kWh | £534 | 11.2 years |
| South-west | 3,515 kWh | £522 | 11.5 years |
| East | 3,024 kWh | £454 | 13.2 years |
| West | 3,024 kWh | £454 | 13.2 years |
| North | 2,079 kWh | £336 | 17.9 years |
With a battery
A battery slows payback to 20.7 years here. It adds about £179 a year for £4,600, and a battery lasts 10 to 12 years, so it is bought twice over the life of the panels.
| Result | Panels only | With a 5 kWh battery |
|---|---|---|
| Upfront cost | £6,000 | £10,600 |
| Used at home | 19% of output | 52% of output |
| Saving and export a year | £556 | £735 |
| Payback | 10.8 years | 20.7 years |
| 25 years, after costs | £7,097 | £2,114 |
Export tariff
The export rate moves payback more than where you live. The same system pays back in 8.3 years at 17.5p and 19 years at 4.1p.
| Export rate | Saving and export a year | Payback |
|---|---|---|
| 4.1p flat SEG rate | £315 | 19 years |
| 12p, Outgoing Octopus | £556 | 10.8 years |
| 17.5p installer-linked rate | £725 | 8.3 years |
Month by month
July makes about 3.4 times as much as December. April to September carries most of the year's output, so no home battery covers a winter in southern England.
| Month | kWh |
|---|---|
| January | 152 |
| February | 198 |
| March | 321 |
| April | 423 |
| May | 442 |
| June | 454 |
| July | 456 |
| August | 409 |
| September | 353 |
| October | 255 |
| November | 180 |
| December | 136 |
Compared with other regions
The whole of Great Britain pays back within about two years of each other. Roof direction and the export tariff matter more than the region.
| Region | Generation a year | Saving and export a year | Payback |
|---|---|---|---|
| South and East England | 3,780 kWh | £556 | 10.8 years |
| The Midlands | 3,540 kWh | £526 | 11.4 years |
| North England | 3,400 kWh | £505 | 11.9 years |
| Wales | 3,540 kWh | £526 | 11.4 years |
| Scotland | 3,180 kWh | £477 | 12.6 years |
Work out your own roof, system size and battery in the solar panel calculator, or read solar panel payback in the UK.
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Frequently asked questions
How long do solar panels take to pay back in southern England?
About 10.8 years for a typical 4 kW south facing system costing £6,000, at the October 2026 price cap and a 12p export rate. It earns about £556 a year and leaves about £7,097 over 25 years.
Are solar panels worth it in southern England?
On a reasonable roof, yes: a 4 kW system pays for itself in about 10.8 years, well inside a 25 year panel life. An east or west roof takes about 13.2 years, and a battery stretches it to 20.7 years.
How much electricity does a 4 kW solar system make in southern England?
About 3,780 kWh a year on a south facing roof, using 945 kWh per kW: the PVGIS figure for homes across the region, less 7% for shading and dirt. Enter your postcode in the solar calculator for your own area. July makes about 3.4 times as much as December.
Data sources
- European Commission Joint Research Centre, PVGIS 5.3: generation by region and month, queried September 2026.
- MCS, MGD 003 Solar PV Self-Consumption: the share of output used at home.
- Ofgem price cap October to December 2026; export rates from the suppliers, 25 September 2026; costs checked against DESNZ solar PV cost data, May 2026.
- Map: Office for National Statistics, ITL1 boundaries January 2025, Open Government Licence v3.0. Contains OS data © Crown copyright and database right 2025.