My thoughts on nuclear power are similar to my thoughts on the death penalty. I have a degree in physics. I am in total agreement with you about the relative benefits of nuclear. Including Fukushima and Chernobyl, nuclear kills fewer people in a bad year than coal does in a good year
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Thermodynamic inefficiency. You know how your car has a radiator? Or a nuclear power plant has a cooling tower? That's how those "heat engines" "reject energy". There are some ways to improve on the amount of energy that is "rejected", such as "cogeneration", where, for instance, the heat "rejected" by a power plant is used to heat the homes in the neighborhood, but other than that, it's thermodynamically unavoidable.
The efficiency of a plant (compared to optimal" can be easily checked by looking at the *temperature* at which that plant spills heat. Older, less efficient plants spill heat at near the boiling point of water. Newer, more efficient plants spill heat at closer to ambient.
In the case of the electrical grid, transmission losses are also "rejected energy". Running a lot of power through wires heats them up, which heat is then radiated into the air, and that energy is lost.
You're right! That is very interesting! So, let's have a quick look at the components of that increase!
Waste energy from grid energy production dropped, 26.29 to 25.8 residential went from 2.32 to 3.98, a dramatic increase. Commercial went from 1.66 to 3.01, another dramatic increase. Industrial was virtually unchanged 5 to 4.9 transportation went from 20.21 to 21.3, a minor increase.
so the major increases in rejected energy were in residential and commercial consumers. Why would that be over that time? And there wasn't much of a change in the energy inputs to either of those over the same period of time.
Lacking a better explanation, I am going to say that it was probably a difference in the accounting methodologies between the time-frames. For instance, the heat that is used to "heat the outdoors" can either be counted as waste, or useful, depending on the accounting methodologies. Really, I can't see anything else that fills that gap. Do you have a better suggestion?
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The efficiency of a plant (compared to optimal" can be easily checked by looking at the *temperature* at which that plant spills heat. Older, less efficient plants spill heat at near the boiling point of water. Newer, more efficient plants spill heat at closer to ambient.
In the case of the electrical grid, transmission losses are also "rejected energy". Running a lot of power through wires heats them up, which heat is then radiated into the air, and that energy is lost.
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Waste energy from grid energy production dropped, 26.29 to 25.8
residential went from 2.32 to 3.98, a dramatic increase.
Commercial went from 1.66 to 3.01, another dramatic increase.
Industrial was virtually unchanged 5 to 4.9
transportation went from 20.21 to 21.3, a minor increase.
so the major increases in rejected energy were in residential and commercial consumers. Why would that be over that time? And there wasn't much of a change in the energy inputs to either of those over the same period of time.
Lacking a better explanation, I am going to say that it was probably a difference in the accounting methodologies between the time-frames. For instance, the heat that is used to "heat the outdoors" can either be counted as waste, or useful, depending on the accounting methodologies. Really, I can't see anything else that fills that gap. Do you have a better suggestion?
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