GAGUA Pro

The number of daylight and sunlight hours in a day impacts the performance of a solar PV system.  On days when it is overcast or raining, electricity will need to be purchased from the local utility.  When your installer is designing your system, he/she will take into consideration historic annual climate/sunlight information (that is available from a number of government and private sources) for your region.  The system should be balanced such that credits accumulated (with the utility) during the summer months will offset the cost of electricity purchased from the utility in the winter months.