When it comes to energy usage and electricity bills, two terms that are constantly thrown around are watt and kilowatt. On paper, the idea that the more you use of either, the more you pay makes sense, but do you really understand what a watt and kilowatt are? Without a grasp on that, it is likely that you have trouble figuring out how your electric company calculates the amount of energy you consume on a monthly basis. Payless Power, a retail electric company providing cheap electricity in Texas with low power company rates, can help you understand and make sense of all the terminology associated with electricity.
Measuring a unit of a kilowatt hour (kwh)
A watt refers to the rate of electricity used for a particular instant and is the most basic measure of electric power. On a microscopic level, watts describe the speed that electrons are moving about at. A kilowatt is the term given to 1000 watts of power. Often electricity providers charge customers a rate per kilowatt-hour(kWh), which can also be a confusing concept. A kilowatt-hour refers to using 1000 watts of electricity over the course of an hour and the number of kilowatt-hours you use is calculated on a monthly basis, for which you are subsequently charged for that usage amount. Sometimes watt-hours are used instead of kilowatt-hours. A watt-hour is just 1/1000th of a kilowatt hour, meaning that 1000 watt-hours is actually just one kilowatt-hour. All you need to do is divide watt-hours by 1000 watts to determine kWh. In the event you have consumed energy for 5000 watt-hours, you would be charged for 5 kilowatt-hours.
If you’re still confused, the following examples about the cost of running some common household devices should help to make this easier to understand.
Consider the following kwh example
- A 100-watt light bulb used for 500 hours during the month would mean it used 50 kWh.
The math behind this is a bit tricky, but think about it this way. The bulb is using 100 watts for 500 hours, meaning that is uses 100 watts x 500 hours = 50000 kwh. Now to convert that to kilowatt hours, all we have to do is divide by 1000 watts and we are left with 50 kWh.
Consider this one:
A large window air-conditioning unit using 1500 watts for ten hours during the month would equal 15 kWhs used.
In this example, a unit of 1.5 kilowatts being used for ten hours becomes 1500 watts x 10 hours = 1.5 kilowatt hours. Now that we have it in watt-hours, we can once again convert it to kilowatt-hours by dividing by 1000 watts. 15000 watt-hours then becomes 15000 watt-hours/1000 watts = 15 kWh. Catching on?
Try this last example:
A small window air-conditioning unit using 500 kilowatts of electricity for ten hours during the month would equal 5 kWhs used.
Just like before, we take our watts used and multiply it by the hours the appliance was in use. In this case, 500 watts x 10 hours = 5000 watt-hours. From there, we divide by 1000 watts and are left with 5 kWh.
You might have picked up on it, but the formula for calculating kilowatt-hours is:
Wattage x hours used divided by 1000 x price per kWh = the cost of electricity used
Electric companies’ rates vary by location, but the rate is always measured in kWhs used. For instance, the average price of residential electricity in the United States in August 2011 was $0.12/kWh, ranging from only $0.082 in Washington State to $0.29 in Hawaii! When it comes to your total kilowatt-hour usage per year, though the amount of electricity you use will vary based on where you live, the average American household will incur charges for around 11000 kWh. Hopefully after reading this explanation, Payless Power has helped you to make some sense of what’s watt and kilowatt!