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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.

I agree with most of what you say and I previously mentioned those very things in my posts 41 and 43 and a few others. I just realize there might have been some confusion when I wrote, "You can't use megawatts. You can used energy (joules) at the rate of so many megawatts."

What I mean by that is not that you can't use the TERM 'megawatts' but that you can't use (in the sense of 'consume' or convert in some way) megawatts themselves. Energy is something you can use. Power is NOT something you can use since it is not a commodity but the RATE of using the commodity. You do not buy power (watts). You buy energy (watts times time). Therefore, what I was trying to say was that you CAN use (consume, convert) energy but you CAN'T use power.

You mention that they could have used the term 'watt hours'. I doubt if there are many reporters who know the difference between 'watts' and 'watt hours', assuming 'they' was a reporter.

You said, "Power plants are often described by the power they can generate..." 'Power' plants don't generate power! The generate (or convert) energy. Power is only an indication of how much energy they generate per second or some time interval.

I go back to my analogy that speed is to distance as power is to energy. Speed and power are time rates. The thing you want to get (distance or energy) is the product of that rate times some time. When you ride a plane, they don't generally charge you for speed, they charge for distance. The electric company doesn't charge you for power, they charge for energy.

The 'power' meter on my house spins faster when I use more energy per second. The speed of its rotation corresponds to my 'rate of energy use' (power), but I am using energy, not power. If I told the electric company I wanted to buy 1000 watts (with no length of time specified), they should tell me it is not possible. If I told them I wanted to buy 1000 watt hours, they should be able to do that. I am being picky on the terms but I want to make sure they are used correctly.