How many batteries do I need?
If you're grid-tied, you don't need any. If you are off-grid, you'll need to know how much energy you use each day. You can then choose enough batteries to give you one or more days of battery power. These are known as days of autonomy. A typical house in Alberta uses about 36 GJ of electrical energy a year, averaging 108 MJ per day. An off grid system with batteries for one day of autonomy for such a house would cost approximately $100,000 all up. For this reason we advise most people to adopt significant energy saving strategies prior to going off-grid.