Is ethanol the answer (part 2)

Yesterday, I posted the first installment of this series of posts on the merits (or lack thereof) of using ethanol in lieu of gasoline.

In that post I reached the conclusion that the use of corn-based ethanol-gasoline blends does very little, if anything, to reduce the emissions of greenhouse gases because the energy from non-renewable fossil fuels required to produce the ethanol is almost as much as the energy in the ethanol itself. However, much of the non-renewable energy used to produce ethanol comes from coal and natural gas, not petroleum, so the use of ethanol does tend to reduce our dependence on foreigh oil. But, as I said in that post, that's not the end of the story.

These estimates are based on current corn yields per acre, the best of current production technology, and current production levels. If ethanol is to be used to displace gasoline in any significant way, all these things will change.

First, the increased demand for coal and gas to produce ethanol will drive up their prices relative to petroleum, leading both ethanol producers and others to switch from coal and gas to petroleum, thereby substantially reducing the only major benefit of ethanol – the reduced dependence on foreign oil. Further, with less coal and gas available for other uses, petroleum is more likely than other fuels to fill the gap.

Second, even if ALL the corn now produced in the United States were turned over to ethanol production, that would only make enough to displace 15% of the gasoline now consumed here. Meanwhile, other less suitable crops would have to be grown to replace the corn now used for animal feedstocks and human consumption. If ethanol is to make any serious impact on foreign oil dependence, significantly more corn would have to be produced. One assumes corn is currently grown in places where it has the highest yield. As more corn is required, less suitable land will need to be used. Yields per acre will fall, and the need for energy consumptive fertilizers, insecticides, etc. increased. Once again, the assumptions on which the energy estimates were based will be wrong.

There is, of course, the possibility that better production technologies and, perhaps, genetically altered strains of corn could offset some of those impacts, but on the whole, the energy balance looks as though it will be poorer than the current estimates. Hence, any greenhouse gas benefits would likely be minimal at best, and the use of corn-based ethanol in large quantities might actually increase greenhouse gas emissions significantly. Further, any benefits in terms of reducing dependence on foreign oil would likely be small, particularly as compared with alternatives, such as the conversion of coal to gasoline. Using known production techologies, Montana alone has enough coal to fuel the country for years to come without any need for foreign oil.

Finally, if corn-based ethanol is used extensively, vast stretches of farmland would have to be converted to corn production. To give you some idea of the magnitude of the problem, to fully replace gasoline with corn-based ethanol would require the conversion of every single acre of cropland in the country to corn production, and even that might not be sufficient. Cleary, an substantial use of ethanol is going to displace other crops. The social and political costs of that displacement are unclear but real.

Frankly, I don't see any significant benefits from substituting corn-based ethanol for gasoline. Yet, our government, and many state governments, are offering huge subsidies to encourage its production. Much of this is due to the political power of the farm lobbies. Whatever the cause, it appears to me to be bad public policy.

One last question, still to be addressed in my next post on this is whether alternative sources of ethanol offer a better solution.