How much will solar panels produce in Southampton?

A 4 kWp system facing south at 35° tilt in Southampton produces about 4,323 kWh a year. In a weak year that is 3,606 kWh, in a good one 5,040 kWh — 1,081 kWh per kWp.

That’s about 160% of a typical home’s yearly use (2,700 kWh).

Calculate for my roof

Based on 2014–2023 satellite weather data

Production by month

0200400600800JanJanuary: 4 kWp 161 kWh, range 128–194FebFebruary: 4 kWp 222 kWh, range 169–274MarMarch: 4 kWp 373 kWh, range 278–468AprApril: 4 kWp 502 kWh, range 402–602MayMay: 4 kWp 517 kWh, range 401–633JunJune: 4 kWp 559 kWh, range 448–670JulJuly: 4 kWp 542 kWh, range 433–650AugAugust: 4 kWp 487 kWh, range 397–577SepSeptember: 4 kWp 412 kWh, range 328–497OctOctober: 4 kWp 270 kWh, range 218–323NovNovember: 4 kWp 185 kWh, range 138–233DecDecember: 4 kWp 133 kWh, range 98–169

kWh per month

A typical day in June

The sunniest month in Southampton. Output peaks around 12:00 solar time, at about 2.2 kWh in the best hour.

0:006:0012:0018:0023:00 2.2 0

Month by month

Month Weak year, kWh Typical year, kWh Good year, kWh
January 128 161 194
February 169 222 274
March 278 373 468
April 402 502 602
May 401 517 633
June 448 559 670
July 433 542 650
August 397 487 577
September 328 412 497
October 218 270 323
November 138 185 233
December 98 133 169
Year 3,606 4,323 5,040

The months don’t add up exactly to the yearly figure, because each one is the typical value across many years.

Common questions

How much do solar panels produce in winter in Southampton?

From November to February the system produces about 701 kWh, which is 16% of the year. The weakest month (December) gives roughly 133 kWh.

Is an east-west roof worth it in Southampton?

An east-west system typically produces 10–25% less per kWp than one facing south, but spreads production more evenly through the day. The exact difference depends on tilt and shading.

Compare an east-west roof for Southampton

Ground mount or roof in Southampton?

A ground mount can be tilted and aimed freely, which can add some yield, but it costs more and needs space. Compare both for your own plot.

Check a ground-mounted system in Southampton

Your roof is not an average roof

Set your own tilt, direction, shading and inverter limit and get a range for your address.

Calculate for my roof

All cities in United Kingdom

Climate data: Photovoltaic Geographical Information System (PVGIS) — European Commission, Joint Research Centre