AMHERST, Mass. – George Huber, a researcher at the University of Massachusetts Amherst, is one of three experts invited to speak next week in Washington at a National Science Foundation briefing on “green gasoline,” an alternative fuel made from plant material.
Not only can liquid fuels now be produced from non-edible cornstalks, waste paper, tree bark and other waste wood, but Huber and colleagues have also developed a way to produce gasoline and diesel fuel in a single, one-minute step, rather than the five- or six-day process once required. The new technique removes a major roadblock to mass production.
Huber, the Armstrong Professional Development Professor of chemical engineering at UMass Amherst, will brief national media on details of how “green gasoline” is made and will also take part in a panel discussion at 2 p.m. on Tuesday, Sept. 23 at NSF headquarters. A similar event for congressional staffers is planned for the following day on Capitol Hill. The other featured speakers are John Regalbuto, professor of chemical engineering at the University of Illinois at Chicago and director of the NSF’s Catalysis and Biocatalysis Program, Randy Cortright, CTO of Virent Energy Systems of Madison, Wisc., and Massachusetts Sen. John Kerry.
The new process developed at UMass Amherst is called catalytic fast pyrolysis. It uses lignocellulosic (plant-based) biomass that is usually thrown away – rigid plant stems, bark, waste wood and even discarded paper that often ends up in landfills – to produce a high octane liquid fuel. This can be added to home heating oil, regular gasoline or diesel fuel without loss of mileage or energy efficiency. Cellulosic biomass is “the only renewable source we have to make liquid fuels,” Huber points out. “And now in a single step we’re going from biomass to gasoline.”
The process starts with heating chopped biomass in the absence of oxygen, then adding an inexpensive, non-toxic powdered catalyst, zeolite, to the mix in a closed chamber. The main products of the reaction are gasoline, diesel fuel, carbon dioxide and water. “We’ve proven this method on a small scale in the lab,” says Huber, and work is well on the way to implementation on a larger scale, with abundant biomass available, for producing economically significant amounts of fuel.
Supplementing petroleum-based fuels with “green gasoline” can save anywhere from $10 to $30 per barrel of oil equivalent, Huber says. That is, if oil costs $110 per barrel, the amount of wood needed to produce the same energy from a biofuel costs $14 in today’s market. “It’s cheap,” Huber notes, “and we have a lot of it.” Lignocellulosic biomass has the added advantage that it is not a food crop; even animals that can digest cellulose can’t get energy from stalks, waste paper, bark, scrap wood or sawdust.
It should also be noted that there will always be a need for liquid biofuels, even as scientists develop photovoltaic cells and solar panels to serve electric-powered passenger cars and other light vehicles. This is because larger vehicles such as trucks, construction equipment, jet planes, trains and military tanks are too heavy to carry electric storage batteries. Thus, large amounts of specially blended liquid fuels must be produced to power heavy machines, Huber points out.
Experts estimate that the U.S. has plenty of under-used biomass available to be fed into the new process, without reducing gas mileage, without the drawbacks or delays caused by changing existing land use, and without adding to greenhouse gas emissions through processing. Further, biomass is not concentrated (like oil) in certain locations, so multiple local biofuel production points are not only possible but preferable. In fact, in order to control post-production transportation costs, it’s estimated that a local facility would most efficiently employ workers within a radius of 50 to 75 miles and could produce the liquid biofuel equivalent of 10,000 to 20,000 barrels of oil a day.
Lignocellulosic biofuels also can be carbon-neutral if efficient conversion methods are used, Huber and colleagues say. That is, the amount of carbon dioxide produced during fuel production and combustion will be equal to the amount consumed by the plants during their growth.
Nearly a dozen Massachusetts-based companies are either exploring or already produce biofuels, according to estimates. In July, the state became the first in the nation to pass a package of incentives including the Clean Energy Biofuels Act, a state gas tax exemption for cellulosic biofuels. Recent scientific breakthroughs such as the one at UMass Amherst represent rapid progress toward inexpensive, practical alternative fuels, which has resulted in serious interest from some of the world’s largest petroleum companies.