My installation is a small one with 8 x 335W panels and 8 x 100Ah batteries in a 48V configuration, being able to deliver up to a constant 5kWh. Obviously Summer is a lot better for me where it is only about 1am to 9am I may be using grid power. The solar setup charges the batteries and runs the house during sunshine, and then the batteries carry the load until around midnight, when the charge gets down to 65%. If there is no grid power the batteries will continue down past 65% and the moment grid power is restored it will use grid power to charge up to 75% if there is no sunlight.
So only on very heavily overcast rainy days will I be getting 200 or 300W charge rate otherwise the system manages to peak at 3,3kW. In general its going really well but it was not installed for cost savings purposes, it was also chiefly to act as house wide UPS for computers and electronics, and to ensure power during South Africa’s frequent load shedding. In this regard it has operated admirably with us being never left without power.
These stats show the monthly savings based on Cape Town’s domestic tariffs. There is R17 to the US$.
See more photos at #^
