A megawatt hour (MWh) is a unit of energy. It is a measure of the actual amount of power consumed or produced by one megawatt expended for a period of one hour. A megawatt (MW) is a unit of power. It describes the rate at which power is being consumed or produced by a circuit at any given moment in time. A megawatt is equivalent to one million watts.
The formula used to calculate megawatthours is Megawatt hours (MWh) = Megawatts (MW) x Hours (h).
To convert megawatt hours to megawatts, you are going to need to divide the number of megawatt hours by the number of hours. In other words: Megawatts (MW) = Megawatt hours (MWh) / Hours (h).

Determine the number of megawatt hours.

Determine the number of hours. (To convert megawatt hours to megawatts, the number of hours must also be known.)

Divide the number of megawatt hours by the number of hours. The resulting number is the number of megawatts.
Tips & Warnings
 For example: You have a highpowered lamp that has used 3 megawatt hours over the course of 6 hours. To figure out how many megawatts your lamp is, you would divide the number of megawatt hours (3) by the number of hours (6) to get 0.5 megawatts.
 Another example: You receive a power bill indicating that your household has used 1,000 megawatts during the previous month. The previous month has 31 days, which means that there were 744 hours in the month (31 days x 24 hours/day). To calculate the average number of megawatts present in all circuits in your house at any one given moment of time, you would divide the number of megawatt hours (1,000) by the number of hours (744) to get approximately 1.34 megawatts. This number would be an average because the amount of power being consumed by your household presumably fluctuates.
 Note that the number of megawatts used in the examples were selected solely for demonstration purposes, and not because they reflect the typical (or even possible) wattage of lamps.
References
 “Wiring Simplified;” 40th Edition; H. P. Richter, W. C. Schwan, F. P. Hartwell; 2002
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