How are Solar Systems Rated

All solar systems are power rated based on the DC wattage output under ideal conditions.  Ideal conditions means high-noon on a cloud free average day.

So a 10kw system generates 10,000 watts of DC power at noon.  This will be less at 9am or 4pm and total generation will depend most highly on how much sun you get where you live.  Our solar calculator allows you to specify where you live to get realisitic AC power output estimates.

AC power is different from DC.  The inverters must convert the DC power to AC for your house.  This conversion is not 100% efficient.  An Enphase micro-inverter is 82% efficient so 250w DC becomes 215w AC.  These are more efficient than the older fashioned "string inverters" that average 78% efficiency.

In any event, it is not simple to determine how large a system is needed to meet your needs nor to determine the annual generation of a specific sized system.  For this reason we have the Solar Calculator that allows you to enter the necessary information to determine your needs and what you can expect to generate.