An average household in the USA consumes around 11,000 kWh of electricity every year. So if we install the average 250 to 300-watt solar panels, we’d need about 30 to 35 solar panels to power up the entire house provided with the favorable weather conditions for the solar panels.
Let’s take two steps further and do the mathematics behind it. For that, we have to consider these three points.
1. How much electricity do you consume?
Determine your electricity usage in kWh. You can find this information manually by estimating the electrical equipment being used at your house, or you can find it on your electricity bill.
2. What is the solar panel production estimate of your state?
Once you find out the amount of electricity you consume, divide it by the solar panel production estimate. 1.31 and 1.61 are the highest and lowest production ratios of the US.
3. What is the average wattage of your solar panel?
Divide the number you obtained in the above step by 250 – the wattage of an average solar panel – to determine a range of how many solar panels you may require in order to produce 100% of your home’s electricity needs.
Let me show you with an example:
· 11,000 kWh of annual electricity usage / 1.32 = 8,333.3
· 8,333.3 / 250 = 33.58 ~ 33 panels.
The above estimation should not be replaced with a professional evaluation. It is only to provide a rough idea to indicate the feasibility of solar panel installation. The number may vary with changing weather conditions, average peak hours, or the required energy.