How much will solar panels produce in Viana do Castelo?

A 5 kWp system facing south at 35° tilt in Viana do Castelo produces about 7,328 kWh a year. In a weak year that is 6,120 kWh, in a good one 8,535 kWh — 1,466 kWh per kWp.

That’s about 244% of a typical home’s yearly use (3,000 kWh).

Calculate for my roof

Based on 2014–2023 satellite weather data

Production by month

02505007501,000JanJanuary: 5 kWp 430 kWh, range 314–546FebFebruary: 5 kWp 448 kWh, range 329–566MarMarch: 5 kWp 605 kWh, range 473–737AprApril: 5 kWp 669 kWh, range 528–810MayMay: 5 kWp 789 kWh, range 650–928JunJune: 5 kWp 764 kWh, range 631–897JulJuly: 5 kWp 832 kWh, range 676–987AugAugust: 5 kWp 817 kWh, range 673–962SepSeptember: 5 kWp 683 kWh, range 557–809OctOctober: 5 kWp 518 kWh, range 388–648NovNovember: 5 kWp 357 kWh, range 231–482DecDecember: 5 kWp 355 kWh, range 255–455

kWh per month

A typical day in July

The sunniest month in Viana do Castelo. Output peaks around 11:00 solar time, at about 3.3 kWh in the best hour.

0:006:0012:0018:0023:00 3.3 0

Month by month

Month Weak year, kWh Typical year, kWh Good year, kWh
January 314 430 546
February 329 448 566
March 473 605 737
April 528 669 810
May 650 789 928
June 631 764 897
July 676 832 987
August 673 817 962
September 557 683 809
October 388 518 648
November 231 357 482
December 255 355 455
Year 6,120 7,328 8,535

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 Viana do Castelo?

From November to February the system produces about 1,589 kWh, which is 22% of the year. The weakest month (December) gives roughly 355 kWh.

Is an east-west roof worth it in Viana do Castelo?

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 Viana do Castelo

Ground mount or roof in Viana do Castelo?

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 Viana do Castelo

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