Posted on 03/04/2007 8:01:09 AM PST by Uncle Miltie
Yes, feedstock is consumption of the resource. The BTU's delivered in the gasoline is part of the consumption, they are no longer available for other use.
production of coal is less energy intensive than gasoline
Agreed, is does take less energy than petroleum products to produce. But your claim is the production of coal as well as gasoline consumes more energy than they contain. There is not that much energy available in the US.
In 2006, the US produced 1,159,880,000 tons of coal.
The average ton of US coal contains 20.34 Million Btu.
U.S. Coal Supply and Demand, 2005 Review
($30.91 per short ton, $1.52 per million Btu => 20.34 million Btu per ton)
So the US consumed 23,592 Trillion Btu in coal. But you claim we need an additional 109% of that energy just to mine, transport and process that coal, another 25,715 trillion Btu. Where does this energy come from? What is the source?
25,715 trillion Btu equals 7,536,323 gigawatthours.
In 2005 the entire US (residential, commercial and industrial) used 3,816 gigawatthours. The industrial only 1,019 gigawatthours. You claim it takes 8 times the electrical energy the entire US industrial sector uses just to produce our coal.
Retail Sales and Direct Use of Electricity to Ultimate Customers by Sector
Since it take more 109% more energy to produce coal than it contains, I wonder where that energy comes from?
You claim gets more ridiculous the farther you take it. How about the claim the oil companies must be selling gasoline for a loss if you are correct? No number like that on the chart, now is there.
No because they count total energy input, not just the process.
In my book, "energy consumed" means "reduction to waste heat, and no longer available to perform useful work"--not "partially burned and partially stored".
"But your claim is the production of coal as well as gasoline consumes more energy than they contain. There is not that much energy available in the US."
I claimed no such thing. Re-read what I posted.
The DEFINITIVE answer is here:
http://www.transportation.anl.gov/software/GREET/pdfs/IJLCA-2004.pdf
in Figure 3.
It takes 250,000 Joules of energy to produce 1 MM Joules of gasoline.
Wang compared apples and oranges when he claimed only the process energy usage for ethanol production and didn't correctly do the same for gasoline production.
If you will go to exhaust pipe of your automobile, you will see the results of just such an action.
I claimed no such thing. Re-read what I posted.
Treating coal the same way says you burn 1.09 MM BTU of energy to produce 1 MM BTU of coal energy.
You are claiming the production of coal takes 109% of the energy contained in the coal. Either both values for gasoline and coal contain the energy content of the fuel, or they both do not.
It takes 250,000 Joules of energy to produce 1 MM Joules of gasoline.
So this study claims the WTP (Well-To-Pump) energy use for gasoline is only 25% of the energy delivered in the fuel. A little high I suspect but well within the realm of possibility. It is far from 123% you were claiming before.
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