Document The Solar UPS.

Essentially this project consists of 2 x 12V x 250W solar panels mounted on the roof in series. These feed an MMPT 24V to 12 solar charger which in turn charges a 12 battery.

The battery is in parallel with a PC power supply (which has been jigged to produce 12.8V). The PC PSU and the 12V SLA feed active diodes in such a way as to ensure the battery is effectively never used (12.8 V being a fully charged battery).

The output of the high power active diode array feeds a 1KVA inverter.

The whole system is controlled by an Arduino board with some custom electronics.

Pics go here.