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Solar PV calculator.
How many kWp does a home or business need, how many panels, and how many years until it pays off? Enter your consumption and get an estimate.
kWp = annual consumption ÷ yield per kWp · Payback = investment ÷ annual savings
How to calculate the size of a solar PV system.
- 1
Consumption
Add up the kWh on your electricity bills for 12 months, or multiply an average month by 12.
- 2
Yield per kWp
In Europe typically 900 to 1,450 kWh per kWp a year, depending on orientation, roof pitch and shading.
- 3
Payback
Savings depend on the electricity price and the grid connection model. The calculator gives an estimate; the exact figure comes with the quote.
FAQ
How many kWp does a home or business need, how many panels, and how many years until it pays off? Enter your consumption and get an estimate.
For 400 kWh a month you need about 4 kWp, with a yield of about 1,250 kWh per kWp a year.
With 450 W panels you need 12 panels, for about 25 m² of roof.
In AdBooks you save panels, inverter, mounting and installation as items and send the PV quote in 5 minutes.