Ultima Thule

In ancient times the northernmost region of the habitable world - hence, any distant, unknown or mysterious land.

Monday, July 03, 2006

The False Hope of Biofuels

By Aussiegirl

Looks like all growing a lot of switchgrass just isn't going to cut it. I don't think there is any real substitute for oil in the near future. We need to drill offshore and we need to develop ANWAR and other domestic sources of oil. We also need to build more nuclear power plants and to explore clean coal technology. The hysteria over offshore drilling is completely misplaced. The real danger of oil spills comes from oil tankers, not offshore rigs. (And for that matter, when was the last major oil spill that you can remember? New tankers with double-hulls seem to have pretty well solved that problem. And even in areas where large oil spills have occurred, the environment has quickly come back, surprising even scientists.) We have plenty of rigs in the Gulf. Have you heard of any environmental disasters on Gulf shores other than ones created by hurricanes? No. But even Republican governors like Jeb Bush have been foolishly coopted into forbidding offshore drilling on their coasts.

The False Hope of Biofuels

Biofuels such as ethanol made from corn, sugar cane, switchgrass and other crops are being touted as a "green" solution for a large part of America's transportation problem. Auto manufacturers, Midwest corn farmers and politicians are excited about ethanol. Initially, we, too, were excited about biofuels: no net carbon dioxide emissions, reduction of oil imports. Who wouldn't be enthusiastic?

But as we've looked at biofuels more closely, we've concluded that they're not a practical long-term solution to our need for transport fuels. Even if all of the 300 million acres (500,000 square miles) of currently harvested U.S. cropland produced ethanol, it wouldn't supply all of the gasoline and diesel fuel we now burn for transport, and it would supply only about half of the needs for the year 2025. And the effects on land and agriculture would be devastating.

It's difficult to understand how advocates of biofuels can believe they are a real solution to kicking our oil addiction. Agriculture Department studies of ethanol production from corn -- the present U.S. process for ethanol fuel -- find that an acre of corn yields about 139 bushels. At an average of about 2.5 gallons per bushel, the acre then will yield about 350 gallons of ethanol. But the fuel value of ethanol is only about two-thirds that of gasoline -- 1.5 gallons of ethanol in the tank equals 1 gallon of gasoline in terms of energy output.

Moreover, it takes a lot of input energy to produce ethanol: for fertilizer, harvesting, transport, corn processing, etc. After subtracting this input, the net positive energy available is less than half of the figure cited above. Some researchers even claim that the net energy of ethanol is actually negative when all inputs are included -- it takes more energy to make ethanol than one gets out of it.


At 9:21 AM, Anonymous Anonymous said...

Liquid biofuels do require much cost to convert - but this is a no brainer.

Corn straight from the farmers combine can cut heat costs by 80%.



Post a Comment

<< Home