Q&A What size does my solar system have to be
 
The easiest way to find out the size of your solar system is by simply having a look at your electricity bill. It should mention the total amount of kW your family used in the time frame mentioned by the electricity company. By dividing the total kW by the amount of days, you’ll discover your daily kW usage.
For example: your quarterly invoice states that you’ve used 2000kW for those 3 months. The calculation would then be: 2000kW / 92 days = 21.7kWh average daily usage.
If you would like to live completely off grid, you’ll need a system that can generate power to cover this estimated daily use. Keep in mind that this doesn’t mean you need 21.7kW of panels, as panels will produce power for several hours each day. In this example a good amount would likely be 5-6kW of panels. For a hybrid system – when you are still connected to the grid – you could opt for a smaller solar system (e.g. 3kW and use the grid as a supplement).
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