Ethanol production is energy inefficient, requiring considerably more energy input than is contained in the ethanol produced.

Ethanol produced from corn causes environmental degradation from increased soil erosion and aquifer mining, from soil, water, and air pollution, and from increased emissions of global-warming gases.

Ethanol produced from corn is not a renewable energy source. Its production adds to the depletion of agricultural resources and raises ethical questions at a time when food supplies must increase to meet the basic needs of the rapidly growing world population.

—The above and below figures are from Food, Energy, and Society by David and Marcia Pimentel, revised edition 1996, pg. 261-68. Ethanol is the type of alcohol. BTU is a British Thermal Unit, the amount of heat that is required to raise 1 pound of water 1° Farenheit. ]

BTU input per gallon of ethanol

Energy inputs for corn per Acre (BTUs)
labor (?)  
0
machinery  
163,000
gasoline  
520,000
diesel  
1,080,000
irrigation  
2,840,000
electricity  
144,000
nitrogen  
5,107,000
phosphorous  
757,000
potassium  
384,000
lime  
2,141,000
seeds  
832,000
insecticides  
160,000
herbicides  
640,000
drying  
1,970,000
transport  
280,000
Total  
16,423,000
BTU Inputs per gallon at 110 bu/yield per Acre
Corn
56,720
 
Transport
610
 
Stain, Steel
1,348
 
Steel
2,106
 
Cement
909
 
Plant, other
2,800
 
Water
1,364
 
Electricity
5,160
 
Fuel
60,000
 
Operating (?)
0
 
Total
131,017
 
 
BTUs per gallon Ethanol
76,000
 
Energy credit for by-products
32,000
 
Energy Return
108,000
 
Net Energy Gain
-23,017
 

This underestimates the true energy cost because it does not take into consideration the human contribution, every action of which has an energy cost and of differing qualities —some contributions are made possible only with extensive education. Nor does it calculate the cost in terms of lost agricultural potential, the erosion of soil 18 times faster than it is replaced, or the groundwater pumping 25% faster than the recharge rate. Thus, it is not an emergy study, which would find the concept of growing corn for alcohol to fuel cars even more absurd and a loser. This, of course, doesn't mean that government won't push it, particularly if there is somebody with fat pockets passing cake to the politicians, to make those pockets even fatter.

[ Ralph Nader shows his lack of comprehension of the magnitude of the energy problem with the trite phrase, "no nukes ever again, and carbohydrates instead of hydrocarbons", without explaining to us how the carbohydrates from biomass are not going to be a net energy loss, and without mentioning that even if it were possible to some slight degree, the result would be a world unimaginably different from the present. By putting forth meritless feel-good solutions to this most difficult passage in human history —transition from growth to non-growth along with the peaking of oil— the US Green Party falls on its schnozz. ]

This wider type of consideration is important with such as photovoltaic cells. There are reports that such and such solar cell has an energy payback of 3 years for example. When one goes to purchase the solar panel, the cost is so high that the payback period for the buyer is many times higher than the energy relationship suggests —in other words, the price of the solar cell is many times more than 10 times what was paid for the energy to create it, which is the simple energy ratio that would apply for a 3 year payback when the life expectancy is 30 years.

U.S. General Accounting Office and Pimentel

Peak Soil: Why Biofuels are Not Sustainable and a Threat to America's
National Security

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