The United States needs a new energy source that is renewable, sustainable and domestically secure. One promising solution that meets all of these needs is cellulosic ethanol.
We are a nation addicted to our cars and trucks, which rely on gasoline made from petroleum, a finite resource on this planet. Once it's used, it's gone. Despite this, each year Americans drive more and consume more gasoline. The U.S. also imports about two-thirds of all the petroleum it uses, and the vast majority of the world's oil resources are in politically unstable regions.
To reconcile these dilemmas, we need an energy source that is renewable, sustainable, and domestically secure. Since two-thirds of all oil is used for transportation, the energy source must also be usable in vehicles. One promising solution that meets all of these needs is cellulosic ethanol, and two Dartmouth engineers are leading the charge on many fronts to make it a feasible alternative fuel.
Charles Wyman and Lee Lynd, both professors at Dartmouth's Thayer School of Engineering, are experts in converting cellulosic biomass (such as agricultural leftovers, grass crops, paper pulp and yard waste) into ethanol. Their combined experience and expertise are sought after by policymakers, business leaders, and researchers nationwide.
"When made from cellulosic materials, ethanol has tremendous potential to be competitive as a transportation fuel," says Wyman.
There are several features that make cellulosic ethanol attractive. The raw materials, cellulosic biomass, are available on a large scale, and they are cost-competitive with petroleum on both an energy and a mass basis. The technology to convert these materials to cellulosic ethanol is steadily improving, and it also has the potential to be cost-competitive with gasoline production. Environmental benefits include a sustainable carbon cycle with near-zero net greenhouse gas emissions, because the carbon dioxide captured growing the biomass roughly equals what is emitted while running an engine. In addition, ethanol has excellent performance and compatibility with existing internal combustion engines and fuel cell-powered vehicles of the future.
Wyman and Lynd's work takes place on many levels. They conduct research to develop more cost-effective conversion technology while simultaneously analyzing the economic and industrial issues associated with establishing cellulosic ethanol as a commercial reality in the transportation sector. They both supervise busy laboratory research groups. Wyman actively consults with industry and is deeply involved in efforts to establish the first commercial cellulosic ethanol facilities. Lynd plays a leading role in technical and policy analysis to define technological potential and transition paths associated with using biomass.
"We're trying to make a difference in an area that I refer to as the sustainable resource transition," says Lynd. "In other words, the transition from our nonsustainable present to a sustainable future."
"We want to develop a technical foundation based on fundamental principles that facilitates confidence in cellulosic ethanol applications, accelerating its entry to the market, and also leads to technical advances," adds Wyman.
They're not starting entirely from scratch. Currently, a small commercial market for ethanol exists; it's blended with gasoline in some parts of this country.
"About two billion gallons of ethanol are made from corn each year," says Lynd. "It's not blended with all gasoline, however. For example, we don't use this blend n New England, but you get it in the Midwest. Flexible fueled cars that burn up to eighty-five percent ethanol in gasoline are also available. All vehicles run well on ten percent blends."