Could a fossil fuel replacement, such as switchgrass pellets, be used to generate heat and electricity?
Roger Samson’s voice is tense with frustration as he discusses the sudden enthusiasm for ethanol made from switchgrass, an energy solution he championed in 1991, but has long since abandoned as too expensive, wasteful, and difficult to produce.
“At one time I was a believer–I used to write about cellulosic ethanol 17 years ago,” says the executive director of REAP-Canada, a nonprofit association that has been researching sustainable agriculture for food and fuel since 1986.
“But I lost faith because of the delays and costs [of]. The most expensive energy is liquid biofuels–it’s simpler to burn fossil fuels than to develop a bio-refinery to produce ethanol.”
Call It “green coal”
Samson is still singing the praises of switchgrass, but now he argues that burning it in pellet form as a replacement for coal makes more sense economically and environmentally. The technology exists–there are about 450 pellet-producing plants in Europe–and it saves on the cost of converting switchgrass to liquid. Another advantage is that it squeezes the most energy out of the biomass (about 60 percent more than ethanol).
He likes switchgrass for the same reasons the researchers behind a report in the National Academy of Science Journal concluded that switchgrass is better than corn for ethanol. The prairie grass is a fast-growing perennial that thrives on marginal farmland, with minimal cultivation and chemicals.
Researchers, who ran a life-cycle analysis over five years, measured the total carbon costs and found switchgrass ethanol could generate 500 percent more energy than was needed to produce it. On the test farm itself, the greenhouse gases (GHGs) were 94 percent lower than for comparable energy from gasoline.
Switchgrass is the current darling of the North American ethanol industry, which has been criticized for its carbon-heavy production costs, including a heavy use of coal, water, and pesticides.
Add the rising grocery bills that go with using food crops for fuel to the US concern over its foreign oil dependency, and it explains the enthusiasm for the fast-growing grass as a biomass to rival Brazil’s sugar cane.
Ethanol too Expensive
The lingering question about ethanol is the one Samson poses: why focus research and resources on a gas substitute when liquid fuel makes the smallest contribution to Canada’s carbon footprint?
Transportation accounts for about 25 percent of the GHGs in Canada, while other demands such as heating homes and businesses, or fuelling industries such as steel mills, or producing the energy itself, account for the majority of emissions.
Samson argues that a fossil fuel replacement, such as switchgrass pellets, could be used to generate heat and electricity. That would lower GHGs faster, especially if green electricity was used to power cars, too.
Samson makes a compelling case, and in February he delivered his research in a brief to the House of Commons’ Committee on Agriculture. Green heat and power lowers emissions anywhere from 87 to 98 percent, when compared with coal.
When it comes to measuring costs, Samson factored in the various subsidies and looked at the price of mitigating GHGs on a cost-per-ton basis. Green energy reduces the GHGs at a cost of between $25 and $50 a ton.
“The most expensive alternatives are liquid biofuels costing $98 (canola biodiesel), $114 (soybean biodiesel), and $378 (corn ethanol) per ton,” Samson writes in his brief. “From the standpoint of costs to the Canadian taxpayer, transportation fuels have been found to be, on average, the most expensive option for reducing greenhouse gas emissions.”
Keep Focusing on Conservation
Keith Stewart, a climate analyst for the World Wildlife Fund of Canada, isn’t opposed to ethanol, depending on how it’s produced, but he says it’s of limited use in the fight against global warming. He suspects ethanol gets all the press because, for the average citizen, the car is crucial and people are hoping for a magic fuel that will allow them to maintain their consumption levels.
“Energy conservation is just not sexy,” Stewart says. “But we can’t meet the current demands with renewable fuels. The number one thing is to reduce.”
The WWF’s prescription for global warming includes finding substitutes for essential fossil fuels, but it emphasizes efficient energy use and reduction through social changes. Instead of relying on ethanol for transportation, Stewart suggests that effective public transit is the realistic solution, along with more efficient vehicles, including plug-in hybrids that use green electricity.
About half of the transportation-related emissions come from vehicles for personal use, and slightly more than half of those emissions can be attributed to SUVs. He says changing behaviour would reduce the need for a gas substitute.
While experience has taught environmental analysts to be cautious about supporting any of the fossil fuel substitutes, Stewart is more optimistic about switchgrass pellets than he is about switchgrass ethanol.
“REAP has been doing solid, long-term research on this–it’s no flash in the pan. It’s one of the most promising bioenergy sources,” he says.
Ethanol No Quick Fix
Jose Etcheverry, a lecturer in York University’s Environmental Studies program, calls developing North American ethanol a waste of time and resources.
“The energy return is marginal. We need to look at policies to mandate energy efficiency rather than policies to replace fuel–increased efficiency is the California standard,” he says, referring to that state’s progressive environmental protection legislation.
Etcheverry, who is also a climate analyst for the David Suzuki Foundation, was so impressed with Samson’s research on switchgrass pellets that he joined the REAP board.
“Not only do you protect the environment, but you are putting farmers back to work and boosting local economies,” he says.
But Samson and his supporters have had little luck persuading policy makers that ethanol isn’t the magic bullet everyone hopes. Since the federal government amended the Environmental Protection Act to make blending biofuels with conventional fuel mandatory by 2012, Canadians have been focused on ethanol and are even importing US corn to feed refineries here.
As Samson phrases it, the Canadian government is gambling that liquid biofuels will be the winner in the fight against global warming–despite all the research to the contrary.
“No government has ever had a good track record in picking winners,” Samson says. “They should be setting emissions standards and creating green carbon incentives based on CO2 mitigation through technology.”
Switchgrass Ethanol Attracts High Profile Fans
Despite the high cost of building processing plants to produce so-called second generation biofuels, cellulosic ethanol has some influential supporters.
American venture capitalist Venod Khosla, an electronics engineer who was one of the founders of Sun Microsystems and other computer ventures, believes the US could achieve fuel independence if they switched to switchgrass ethanol. He’s been banging the drum for cellulosic ethanol since 2006. In March 2007 the US Department of Energy committed $1.2 billion to partially fund construction of six cellulosic biorefineries.
Environmentalist David Suzuki has also given cellulosic ethanol the nod. “One promising biofuel that scores well in preliminary studies is cellulosic ethanol made from switchgrass,” Suzuki wrote in a newspaper column comparing switchgrass ethanol to fuel derived from corn. He also sees potential for biofuel made from other biomass including algae and wood pulp. But his blessing comes with a caveat—it all depends on how the biomass is grown, how much land it consumes, and whether forests are removed for its cultivation.