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Solar PV annual output

Estimates a year of generation from a solar array using the MCS standard estimation method.

Follows MIS 3002

The roof and the array

Only the outward code matters. It selects one of the 25 MCS irradiance tables.

Panel wattage times the number of panels, divided by 1000. Twelve 440 W panels are 5.28.

Due south is 0. South-east and south-west are both 45. East and west are both 90. Due north is 180.

A flat roof is 0. A typical British pitched roof is 35 to 45.

1.00 for a clear horizon. Work one out with the shading calculator if anything blocks it.

Nothing is stored. Nothing is sent anywhere.

Your answer appears here

Most of the form is filled in already with figures that give a sensible answer. Adjust what you know and press the button.

What this calculator does

Estimate the annual AC electricity output of a UK solar photovoltaic system, in kWh, using the standard estimation method that MIS 3002 requires every MCS certified installer to use.

The method is: annual output = kWp x Kk x SF, where Kk is read from the MCS irradiance dataset for the site's postcode zone, roof pitch and orientation, and SF is a shade factor between 0 and 1.

Supply the postcode and the array's capacity in kWp, plus the roof's pitch in degrees from horizontal and its orientation in degrees away from due south in either direction, so that south is 0, south-east and south-west are both 45, east and west are both 90, and north is 180.

The result carries the tabulated yield, the estimate, and what the same array would produce at the best pitch and orientation for that zone, so a roof that is merely good is not mistaken for a poor one. This covers the United Kingdom only; the dataset has no values for anywhere else.

Also available to software

The same calculation answers on POST /api/calculators/solar-pv-output and as the MCP tool solar_pv_output. How to call them.

What this is doing, explained

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