UNIVERSITY PARK – “Live green, go yellow,” urges the now often-heard slogan about putting ethanol in the gas tanks of vehicles, with the “yellow” referring to the color of corn, the main source for the biofuel in today’s world.
But in a few years, according to green fuels experts in Penn State’s College of Agricultural Sciences, Pennsylvania will be producing more ethanol from other plants than from corn. “Nationwide we can grow enough corn to produce much of the ethanol that we are projecting to use in the next 10 years or so, but only a fraction of the corn used for ethanol would come from Pennsylvania production,” said Greg Roth, professor of agronomy and extension grain crops specialist. “Research currently is refining the technology that allows us to extract ethanol from cellulosic (woody) plants that can be grown in abundance here, and I think you will see before the end of the next decade that Pennsylvania will be producing a lot of ethanol from other sources.”
Gov. Ed Rendell recently declared that Pennsylvania will inject 900 million gallons of biofuels into the state’s gasoline and diesel supplies over the next decade. The bulk of Pennsylvania’s home-grown energy will eventually come from diverse feedstocks, Roth contended. “My vision, and I think the governor’s vision, is that we will start by producing ethanol from corn but eventually transition over to a more diverse feedstock base,” he explained. “Initially, we could develop a corn ethanol production capacity with established technologies and then transition to other grains and cellulosic sources as that technology comes on line,” Roth added. “I expect that in the future we will be producing a blend of cellulosic and grain-based ethanol.”
Pennsylvania has the potential to produce large amounts of ethanol, maintained Tom Richard, associate professor of agricultural and biological engineering and an expert in the process of extracting ethanol from woody plant materials. “When people talk about ethanol fuel or biodiesel, they think of corn and soybeans, but we don’t produce anywhere near as much of those commodities as the Midwestern states,” he said. “Still, we are blessed with soils and climate to create a lot of biomass. We have lots of pasture land, and there are ways of producing more biomass than with corn. We just need to figure out how to take best advantage of the sunlight.
“That is really what we are talking about – converting sunlight into fuel.”
Warm-season, perennial and even native grasses hold more potential for home-grown energy solutions than corn, according to Richard. “Of
course, switchgrass has gotten all the headlines in the popular press, but there are other grasses we should look at, as well,” he said. “Switchgrass grows well here – but it grows well in 47 other states, too. Other native warm-season grasses, perhaps in combination with cool-season grasses like reed canary grass, might be better at creating biomass for fuel in Pennsylvania.”
Another kind of plant with great potential for ethanol production in Pennsylvania grows wild across the state – trees. Charles Ray, assistant professor of wood products operations, believes just concentrating on a sustainable harvest of smaller, under-utilized “remnant” trees could provide a huge amount of ethanol.
“Pennsylvania’s forests are rich in potential bio-energy from small-diameter trees that are overcrowded, under-utilized, and inhibit he opportunity for professional management,” he said. “The Pennsylvania Hardwoods Small Diameter Task Force analyzed the U.S. Forest Service’s most recent Forest Inventory Analysis data for Pennsylvania and estimated that as much as 500 million tons of wood are held in these small-diameter stems.
“Those small-diameter trees are spread across 16 million acres of forestland in the commonwealth, and Bureau of Forestry mapping reveals that about half of this acreage could be available for harvest,” Ray pointed out. “That is, it is not restricted by environmental, regulatory or ownership restrictions from harvest. Based on this available volume of wood, an annual sustainable harvest of 6 million dry tons of wood per year could be converted into various bio-energy sources.”
According to Ray, 6 million dry tons per year is the rough equivalent raw material usage of 18 wood ethanol plants producing 540 million gallons of ethanol per year. “The potential is awesome,” he said.