Politicians, investors, farmers and car companies are turning their heads to ethanol, a renewable energy source produced from corn and the latest fad in the energy sector, sprouting excitement and controversy alike. Ethanol plants are being built, and already existing factories are expanding. A question remains, however: Is this alternative biofuel a better option than conventional gasoline?

Answering it has been the task of a group of UCSD researchers at the Center for Energy Research.

The three-man team, composed of professors Forman A. Williams and Kal Seshadri, and graduate student Priyank Saxena of the mechanical and aerospace engineering department, is developing chemical models for ethanol combustion that are simpler and more usable than gasoline.

These studies will provide practical data to analyze the potential of engines running on ethanol and will in turn help to track the production of major paths of pollutants from burning the compound.

The alcohol known as ethanol was used as a fuel in the early 20th century before Prohibition criminalized alcohol production, but has recently re-entered the limelight and is now being used as a fuel additive. It replaces the anti-knocking agent known as MBTE, which is being phased out after it was discovered to pollute groundwater.

Ethanol is most commonly used in a blend known as E10, which is 10 percent ethanol and 90 percent gasoline. However, with the development of “flex-fuel” cars specifically built to handle a higher amount of the alcohol, the ethanol industry is pushing for the use of E85, a mixture of 85 percent ethanol and 15 percent gasoline. Currently, there are about five million of these vehicles produced or sold.

This biofuel is produced from plant starch that is transformed into sugar and then fermented and can be produced from corn, sugar cane, hemp or other starchy plants. Most ethanol in the United States is produced from corn.

The current buzz is about cellulosic ethanol, produced from plant material and agricultural waste that is not digestible by humans, such as switch grass and wood chips. It is still too expensive to compete against traditional gasoline.

Ethanol as a fuel source is therefore renewable because it is made from elements that can be grown.

Many investors are excited about its possibilities. A recent article in Fortune magazine detailed Exxon Mobil’s plan to give $100 million to Stanford University to research alternative fuels. Bill Gates, among many others, has declared his intention to invest in ethanol-producing companies.

The U.S. government, however, is one of the biggest ethanol supporters, and has subsidized the production of corn and ethanol. President George W. Bush has said that he sees ethanol as a way to wean America off foreign oil dependency.

“Breakthroughs on this and other new technologies will help us reach another great goal: to replace more than 75 percent of our oil imports from the Middle East by 2025,” Bush said in his State of the Union address in January.

A recent federal bill calls for the production of eight billion gallons a year of biofuels by 2012.

The United States is not the first to experiment with alternative fuels, and is, in fact, following in the wake of countries like Brazil, which has been producing ethanol-running cars since the late 1970s. According to an ethanol study conducted by the Solar Energy Research Institute, up to 90 percent of new cars in Brazil run on pure ethanol produced from sugar cane, with the remainder running on a blend of 20 percent ethanol and 80 percent gasoline.

Although research is not complete, the preliminary experiments and computational studies have shown that, in some aspects, ethanol is better for the environment than gasoline or diesel fuels.

UCSD researchers have found that burning ethanol does not produce sulfur dioxide and has lower concentrations of nitrous oxide — both of which are acid-rain-causing agents. Also, the concentrations of soot precursors, elements that cause unburned carbon residue, are found to be lower compared to those produced by conventional fuels.

In other aspects, ethanol has higher levels of polluting agents, according to UCSD research, such as higher levels of aldehydes, which are known to be toxic for the environment and can cause eye irritation and skin rashes at low levels.

Other studies have shown that ethanol production uses a significant quantity of energy and releases many greenhouse gases responsible for global warming, discoveries that have sparked skepticism over the new fuel technology. Tad W. Patzek, a professor of geoengineering at Berkeley, found that corn ethanol requires 29 percent more energy to create than it produces.

However, graduate student Priyank Saxena argues that this is debatable. He points to a Solar Energy Research Institute finding that ethanol production comes remarkably close to breaking even on an energy basis.

Saxena also argues that levels of greenhouse gases are not higher for ethanol produced from plants. Since plants intake carbon dioxide for their growth, the net carbon dioxide production by ethanol fuel is less than those by conventional fuels, he said.

Even beyond the controversy, several hurdles lie in the path of further ethanol utilization, such as a lack of gas stations that carry the ethanol blend due to the higher cost and the fewer miles per gallon the fuel allows.

Saxena thinks that these obstacles can be overcome and that ethanol is a good stepping stone for energy evolution.

“Ethanol as an energy source is a good interim solution until we are able to accomplish hydrogen economy, fuel cells and cold-fusion technologies,” he said.

Williams emphasizes that more research needs to be conducted before diving into complete ethanol implementation.