Our place at the lake is completely off grid. We did some calcs around sun exposure in hours, and to figure out what we wantef to run. The place is 1200 square feet. Three bedrooms. Composting toilet, propane cook stove and supplemental heat with a woodstove.
We went with a 2400 watt inverter system running 8 210 ampere hour six volt batteries wired for 24 v operation. This gives us a functional reserve capacity of about 5kwh. We have three 135 watt panels for charging -wired in series through an MPPT charger. (the mppt systems give more hours of charging because they are set up to accept greater voltages. This means that they can start charging earlier and keep charging later, and at other times the excess volts are converted to greater amperages.)
We only have had to use the back up genny one time when my FIL was out and kept opening the fridge all the time during a cloudy period.
The system supports lighting in all rooms, a ceiling fan, an efficient fridge, and a dc water pump. We do use a combo of CFL and LED lighting.
The whole works cost just a bit over 11k
Last edited by ptarmigan61; 02-03-2013 at 01:11 PM.
Reason: Adding costs.