My home system consists of 18 Siemens SP-75 Mounted on a Wattsun dual axis tracker. The PV output is connected to a RV Power Products Solar Boost-50. The power is stored in two 1350 Amp hour GBC industrial batteries. During sunny periods the excess power to sold back to the grid using a Xantrex SW4024. The SW4024 is controlled by a small embedded controller which I developed. The controller called the Inverter Master. The Inverter Master monitors the battery voltage and the PV charge rate to determine when to enable “Sell” mode and when to command the inverter to return to “Silent” mode. During grid outages the inverter serves as a whole house UPS. Mostly the inverter remains in the “Silent” mode waiting for the grid to fail or the Inverter Master to command it to sell excess energy to the grid after insuring the batteries are fully topped off. Operating the system in this manor keeps the system from cycling the batteries very hard and places renewable energy on to the grid for my neighbors to use.
