Energy options such as algae are years away
The Arizona Republic
May. 11, 2008 12:00 AM
Ethanol is now a staple in gasoline, used as an additive that reduces the amount of crude oil and cuts back on vehicle emissions.
The 134 ethanol refineries in the country are expected to produce about 9 billion gallons of the fuel this year. Even with some cancellations, dozens of plants are expanding or being built, according to the Renewable Fuels Association. Many have direct ties to corn, with farmers owning 49 plants.
Even if lawmakers succeed in repealing or reducing ethanol-production subsidies, it is required as an additive in some places, including metro areas in Arizona. A 10 percent ethanol blend is added to gas in the Phoenix area in the winter to fight pollution, with a similar requirement in Tucson. It's allowed but not required to make up to 10 percent of fuel blends year-round in the rest of the state.
The Arizona Department of Weights and Measures estimates statewide demand of 100 million gallons a year as an additive, and some stations sell an 85 percent blend that can be used in many American-made vehicles.
"We believe corn ethanol will continue to be an important part of the fuel supply," said Ron Lamberty, a vice president of the American Coalition for Ethanol.
But even its supporters recognize that corn can't power the country. The ethanol production goal of 36 billion gallons set in the recently passed U.S. Energy Bill can't be met with corn alone, Lamberty said.
"You get to somewhere around 15 billion gallons and you've got problems," he said. "Then you've got to have some other sources."
Algae for energy?Beyond the dilemma of using food for fuel, ethanol has efficiency issues. High-concentration blends get about one-third fewer miles to the gallon than gasoline, although the ethanol industry promotes "optimal" blends of 20 or 30 percent that can raise mileage in some engines despite the lower energy content of ethanol.
Ethanol proponents tout corn as a steppingstone to "cellulosic" ethanol. In the cellulosic process, enzymes are used to break down the woody part of plants, rather than just the sugary parts, like corn kernels.
But critics say that technology still won't be efficient enough to justify using cropland and water for fuel. Other potential energy sources are algae and bacteria. At Arizona State University, the Biodesign Institute is working with British oil company BP to study photosynthetic bacteria that can be grown with brackish water to produce oils for biodiesel.
Algae and bacteria are getting lots of attention from energy startups and oil companies because they grow quickly and constantly and a much larger portion of their mass can be converted to fuel than corn.
Making biodiesel also uses the fatty part of algae or bacteria in a chemical process that doesn't require as much energy as distilling ethanol. "Moving to microbial systems, then you start to get real," said ASU researcher Bruce Rittmann, director for the Center for Environmental Biotechnology.
"Instead of the entire surface area of land (like with corn ethanol), it is something reasonable, and you can create energy on a big scale."
But even if the biodiesel technology were perfect today, it would take decades to replace oil with algae or bacteria.
"We are talking about replacing the worldwide petroleum industry," he said.
Replacing oilMany experts agree that no single technology will be able to replace oil. Lamberty suggests blends of 30 percent ethanol or more for cars in the corn-growing states, with other regions of the country playing their fuel strengths.
"These ideas must all be cumulative," said Bill Sheaffer, vice president of marketing for Amereco Biofuels Corp., which collects waste cooking oil from restaurants around the Valley and converts it to biodiesel at a West Valley plant.
"Waste oil has a limit," Sheaffer said. "Then there are non-edible seed oils. And algae has a huge potential."
Amereco is among the dozens of companies around the world growing algae in labs to test it as biodiesel.
Even with the potential of other biofuels, Sheaffer said he supports ethanol, if for no other reason than it reduces the country's need to import gas and oil. "It is a little maddening," he said. "I can't recall any type of alternative energy that hasn't been viscously attacked."