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This week---. Monday: Energy Intensity “EMERGY”– how much energy does it take to extract energy? Reading: wikipedia is ok www.greatchange.org/footnotes-emergy.html Wednesday: Start Ch. 8, Transportation Friday: Transportation. Energy INTENSITY. Energy used per dollar of GDP, or
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This week--- Monday: Energy Intensity “EMERGY”– how much energy does it take to extract energy? Reading: wikipedia is ok www.greatchange.org/footnotes-emergy.html Wednesday: Start Ch. 8, Transportation Friday: Transportation
Energy INTENSITY Energy used per dollar of GDP, or Carbon Intensity Carbon/CO2 per dollar of GDP.
Energy intensity for that coal? 0.7 GJ/ton of product Text --28.1 GJ/ton of coal Gain=28.1/0.7 = 40 TECK.com
Emergy=Embodied Energy How much energy do we have to into a process to have that process give us energy? Machinery to dig coal, trains to haul the coal, steel to build the power plant, copper to make the generator, energy to grind the coal to dust, energy to scrub the gases, copper for the transmission wires,….…… A systems accounting problem.
A Prosperous Way Down :Principles and Policies Howard T. Odum and Elizabeth C. Odum University Press of Colorado or Environment and Society in Florida Howard T. Odum
Examples: emergy yield ratio Farm windmill, 17 mph 0.03 Sugarcane ethanol 1.14 Natural gas/offshore 6.8 Natural gas/onshore 10.3 Century-old rainforest 12.0 emergy yield/emergy of all inputs from the economy
Aluminum can Mass of Rolling Rock can = 14.1 grams Wikipedia says the energy cost from bauxite ore to the electricity to make aluminum is 227-342 MJ/kg. 300 MJ/kg x 14.1 grams/ 1000gram =4.23x106 J Coal holds 2.81 x10 10 J/ton, So we need 4.23 x106J/2.81 x1010J/ton =1.51x10-4 ton= =0.30 pounds of coal
HW #9 due March 15 EXAM #2 Wednesday in class March 17 1.(10) It is desired to fly one liter (1 kg) of Yuppie Water from Suva, Fiji to Denver, a distance of 6329 miles. Neglecting the difference between an English ton and a metric tonne, how many barrels of jet fuel (the same energy content as crude oil) will this require? If that refined fuel costs $100 per barrel, what was the cost of shipping that water? 2.(4) The answer to Problem 1 seems to be costly, so I use an old airplane that flies with the same ‘drag coefficient’ and other flight features as the original one, but at half the speed. By what factor does the aircraft power requirement change? By what factor does the fuel consumption to bring that liter to Denver change?
3.(4) Explain in words the contents of Table 8.4, and use some pair of numbers to argue a point to a policy maker. 4.(2) People tell us that the 50 mile drive to Denver International Airport is more dangerous than the 1500 mile flight to New York. Use Table 8.6 (2003 numbers and not on an interstate highway) to check this claim.