Estimating Kilowatt Hours from Appliance Labels. 1  1. Find the wattage on the appliance label. 2  2. Multiply wattage by hours used each day. 3  3. Divide the result by 1,000.  4. Multiply your answer by the number of days you're 1  measuring. 5. Multiply by the cost of electricity per  kWh.
http://www.wikihow.com/Calculate-Kilowatt-Hours
An electric heater rated at 1000 watts (1 kilowatt), operating for one hour uses one kilowatt-hour (equivalent to 3.6 megajoules) of energy. A television rated at 100 watts operating for 10 hours continuously uses one kilowatt-hour. A 40-watt light bulb operating continuously for 25 hours uses one kilowatt-hour.
https://en.wikipedia.org/wiki/Watt-hour
In electrical power generation, the distinct ways of generating electricity incur significantly different costs. Calculations of these costs at the point of connection to a load or to the electricity grid can be made. The cost is typically given per kilowatt-hour or megawatt-hour. It includes the initial capital, discount rate, as well as the costs of continuous operation, fuel, and maintenance.
https://en.wikipedia.org/wiki/Cost_of_electricity_by_source
The unit that both gas and electricity are measured in is kilowatt hours (kWh). One kWh of gas is approximately equivalent to leaving a small gas hob burner on for an hour. One kWh of electricity is the rough equivalent of running a washing machine for an hour.
https://www.ukpower.co.uk/home_energy/tariffs-per-unit-kwh
Idaho had the lowest price, at about 8 cents per kWh. So the typical US household would pay about $73 for electricity each month in Idaho. Hodge says Idaho generates much of its electricity from hydroelectric dams, which require virtually no fuel.
http://www.npr.org/sections/money/2011/10/27/141766341/the-price-of-electricity-in-your-state
Calculate the Costs to Use Electricity. Examine each device that ’ s turned on around you and type its power (in Watts) into this box. (If you want to include more than one device, just separate each device ’ s power intake with a comma.) Example, your TV is on. Type: 115. Example, your laser printer and toaster are on. Type: 580,1200.
http://www.webmath.com/kwh.html
The kilowatt-hour (symbol kWh, kW⋅h or kW h) is a derived unit of energy equal to 3.6 megajoules. If the energy is being transmitted or used at a constant rate (power) over a period of time, the total energy in kilowatt-hours is the power in kilowatts multiplied by the time in hours.
https://en.wikipedia.org/wiki/Watt-hour
The average price people in the U.S. pay for electricity is about 12 cents per kilowatt-hour. (Context: A typical U.S. household uses about 908 kWh a month of electricity.) But there's huge variation from state to state. Here's a map of residential electricity prices, according to the Energy Information Administration.
http://www.npr.org/sections/money/2011/10/27/141766341/the-price-of-electricity-in-your-state
How energy bills are calculated. When calculating the price of your bill, energy providers monitor how many kilowatt hours of gas or electricity you have used over a certain period of time, and then multiply this by the price per unit set in your tariff.
https://www.ukpower.co.uk/home_energy/tariffs-per-unit-kwh
Now you know how many kilowatt-hours (kWh) the device uses every day. To calculate your kWH per month or per year, just multiply by the number of days in that period. Example: Over the course of a 30-day month, your fan would use (1.25 kWh / day) x (30 days / month) = 37.5 kWh per month.
http://www.wikihow.com/Calculate-Kilowatt-Hours
cost of kwh
The cost of a kWh is 12 cents per kilowatt hour. 12 cents per kilowatt-hour.