- Melissa Deaver
KwH for Solar Explained
If you're researching solar, you'll undoubtedly come across the term "kilowatt-hour" or KwH. But what does this actually mean?
A kilowatt is the main unit we use to measure electrical energy. Kilowatt is 1,000 watts. A kilowatt hour is the measure of energy utilized in an hour's time.
If you were to take a look at your energy bill, you would see the KwH's utilized in a given month. This is the amount of energy consumed during that time. If your goal with going solar is to offset your energy consumption by 100%, then you would size your solar system to accommodate this number.
Let's say your home produces around 12,000 kWh per year. To offset, you would want to size a system that is roughly 12kW. For this example, let's say we're going to use 410W panels. This means that each panel produces 410W of power. We would take 12,000 / 410 to equal either 29 or 30 panels. These would produce 11,890kWh or 12,300kWh per year respectively.
The actual size of your system will also depend on your location's net metering policies. For our most utilized energy company, they will net meter up to 125% of production. Meaning if you produce more energy than you're using, they will credit you that amount for up to 125%. With this energy company, we size our systems just above 100%, hoping to capitalize on the surplus.
Of course other factors go into the power produced by your panels. The energy produced depends on the system's energy efficiency rating, age, performance level, orientation and sun exposure. For a super sunny location, you can expect to see a bump in production, even up to 1.5 times.