What is a kilowatt (kW) and what is a kilowatt hour (kWh)?

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A kilowatt is simply 1000 watts of electricity.

A watt of electricity is a measure of power.

Power in turn is a function of the voltage of a circuit multiplied by the current.

Power= Current (Amps) x Voltage
P= I x V

A kilowatt hour is a measure of total energy and it refers to the amount of energy over a period of time:

1 kilowatt hour is equivalent to 1000 watts of power being used or generated for one hour.

So if you were generating 100 watts for 10 hours you would generate 1 kWh.

If you were generating 10000 watts for 6 minutes continually then you would generate.

Kilowatt hours is the standard unit in which power is bought and sold to consumers.


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kilowatt meter on wall

How many kilowatt hours of power does the average house use?

The stats we have on this are based on users of our website who are typically owners of single family homes and given their interest in installing solar panels probably have larger than average usage but from our numbers the average usage of power is around 750 kWh per month, or 9,000 kWh per year.

Our Solar-Estimate solar estimator has all the rates schedules for almost every utility in America in its database and so if you know how much you spend a month on power we can reverse engineer this number to get an approximation of the amount of kWh of power you use per month. From this we can also give you an estimate of the size of solar power system you would need to zero out the usage charges on your power bill.


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