The usual recommendation for an annual electrical use of is 0.5kW of PV
power per 1500 kWh of electrical consumption.
1000 - 1500 kWh a maximum of 0.5 kW of participation is recommended
1500 - 3000 kWh between 0.5 and 1 kW
3000 - 5000 kWh between 1.5 - 2 kW