You can determine how much you are paying for electricity by looking closely at your power bill. Electricity is sold by your utility on a per kilowatt-hour (kWh) basis, with the price of electricity often determined through a regulatory process. Most utilities charge varying rates depending on how much electricity you use.
In the summer, for instance, Rocky Mountain Power changes one rate for usage up to 400 kWhs a month, another rate for usage between 400 and 1000 kWhs a month, and a third rate for all usage above 1000 kWhs. They have different rates for winter too! It can all be confusing to say the least.
As shown in the image below, you can find the rate you pay for electricity by examining the blocks you fall into. This will give you an idea of what to input into the calculator as your utility rate. If you are a Rocky Mountain Power or Murray Power customer this is all done for you! If not, use your power bill to get a good approximation of the rate you pay. You likely pay more in the summer, a time when electricity usage is high, so be aware of your 12 month usage, not just what you are paying this month.
For more information on your utility's rate structure contact them or search for their electric rate tariff.
To download a higher resolution version of this image please click here [PDF].