A reader asks:
My question is about hybrid cars, ethanol, hydrogen, and other fuels and technologies that are often presented and unquestioningly accepted as solutions to climate change. Our collective belief seems to be that we can continue to drive our cars, run our power plants, etc. the same as we do today because one or more of these fuels or technologies will replace fossil fuels in the near future. … Is hydrogen a viable technology? Would putting ethanol into our cars actually reduce emissions to a level that would avoid the worst effects of climate change? With the deep cuts in emissions that are needed over the next few decades to avoid the worst effects of climate change, can we continue to drive as much as we do? Can renewables like solar and wind power be developed at a large scale to replace power plants run by fossil fuels?
OK. This is a huge question but let me take a stab at it in parts.
First, ethanol. This is an alternative fuel that produces relatively little pollution when burned. It’s created from things such as corn and sugar cane and can be used as either a fuel itself or as an additive in the gasoline we currently use. The debate, though, about ethanol has been focused more on its usefulness in reducing our oil demand, not on its climate-change affecting qualities.
I put this question to Bill Powers, a local engineer and energy guy. Because the United States is making most of its ethanol from corn, Powers said, it’s not doing much to cut greenhouse gas emissions. All the energy that goes into growing, harvesting and manufacturing corn-based ethanol consumes about as much energy as simply creating and burning a gallon of gas, Powers said.
“I don’t know anyone other than Midwestern farmers who are banging the drum for that as a real solution,” Powers said.
Sugar cane, though, is a more efficient ethanol source, Powers noted. President Bush is in Brazil today stumping for this.
Bottom line: The benefits of ethanol will depend on its source. Will it ultimately help cut greenhouse gases? The consensus view is yes. But is it a panacea? No.
There’s more to come on this question.