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And here's another:
"On Tuesday, customers across the state used 32,075 megawatts _ enough to power 32 million homes _ between from 4 to 5 p.m."

You can't use megawatts. You can used energy (joules) at the rate of so many megawatts.

But I guess we could keep this thread going just like this until it gets cool. Speaking of cool, the hottest day this month where I am (Cleveland) has been 95, second was 93. Last month we had a 94. Sounds pretty cool compared to what some folks have been getting.

What do you mean when you write in post 67 that one can't use mega Watts?

A Watt is power, one volt*one amp with no units of time. A joule is one amp*one volt for one second. It has a unit of time attached.

In the example you cited, there indeed was a time unit reported, but that is incidental, as the product of power generation (volts times current (amps)) was 32.075*10 6 Watts. So, over that period, if wanted to report the product in Watt hours, they could have since the reported time was one hour, so it is easy to do, if it was three hours at the same level of power, one would multiply the product by three.

Joules are a scientific unit used to describe the same thing as Watt hours or current times volts times time. As one Amp across one Ohm makes one Volt then one Joule is one Watt second.

Power plants are often described by the power they can generate, just like the portable generator one might buy for backup in a hurricane or as we have up here, winter northeasters, that would be in kW or in the case of your local nuclear power plant, in thousands of MW. At the end of the year, to get efficiency, they add up the average power production in MW multiply by the total hours of operation to get Watt hours (actually mega Watt hours) and divide that number by the optimal potential of the power plant if it worked at full capacity every day. This number is the load factor on the generator system. A load factor close to 1 is bad because it leaves no room for growth while a load factor near .3 or .4 is bad as well because they are not using the plant sufficiently to make it efficient with respect to the sunk costs of construction. A load factor of about .8 is ideal. The load factor is also calculated for all other parts of an electrical distribution system, from the high voltage transmission system, to the substations, right down to the residential distribution lines and transformers. When the demand exceeds the capacity you get your brownouts or if the voltage is not reduced (brownout condition) the systems starts breaking down with transformers overheating and breakers blowing, so to reduce the power the voltage is reduced which reduces the current. That is the significance of the reporting of the mega Watt demand on a system.