No. You can thnk of a megawatt hour as the number of megawatts that have been used in one hour.
A
megawatt is a measure of power. A megawatt is 1,000,000 watts or 10
6 watts. A Watt is the same as a Joule/second.
A
megawatt hour is a measure of energy. One megawatt hour is (10
6 watts)*(3600 seconds) or 3.6 * 10
9 watt seconds. Since a watt is a joule/second a megawatt hour is also 3.6 * 10
9 joules with the joule being the SI unit for energy.
You cannot 'use' watts or megawatts. A watt is simply the rate a
t which you 'use' energy. So, the first sentence of the above answer should read: "You can think of a megawatt hour as the amount of energy used in one hour at the rate of one megawatt'.