How much will solar panels produce in Spa?

A 5 kWp system facing south at 35° tilt in Spa produces about 5,083 kWh a year. In a weak year that is 4,172 kWh, in a good one 5,994 kWh — 1,017 kWh per kWp.

That’s about 145% of a typical home’s yearly use (3,500 kWh).

Calculate for my roof

Based on 2014–2023 satellite weather data

Production by month

0200400600800JanJanuary: 5 kWp 133 kWh, range 87–180FebFebruary: 5 kWp 249 kWh, range 162–337MarMarch: 5 kWp 452 kWh, range 331–573AprApril: 5 kWp 584 kWh, range 470–699MayMay: 5 kWp 620 kWh, range 487–752JunJune: 5 kWp 647 kWh, range 517–777JulJuly: 5 kWp 624 kWh, range 488–760AugAugust: 5 kWp 615 kWh, range 493–738SepSeptember: 5 kWp 513 kWh, range 404–623OctOctober: 5 kWp 309 kWh, range 233–385NovNovember: 5 kWp 181 kWh, range 118–245DecDecember: 5 kWp 120 kWh, range 72–168

kWh per month

A typical day in June

The sunniest month in Spa. Output peaks around 11:00 solar time, at about 2.6 kWh in the best hour.

0:006:0012:0018:0023:00 2.6 0

Month by month

Month Weak year, kWh Typical year, kWh Good year, kWh
January 87 133 180
February 162 249 337
March 331 452 573
April 470 584 699
May 487 620 752
June 517 647 777
July 488 624 760
August 493 615 738
September 404 513 623
October 233 309 385
November 118 181 245
December 72 120 168
Year 4,172 5,083 5,994

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 Spa?

From November to February the system produces about 683 kWh, which is 14% of the year. The weakest month (December) gives roughly 120 kWh.

Is an east-west roof worth it in Spa?

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 Spa

Ground mount or roof in Spa?

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 Spa

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

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