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Remember Biofuels?

By Greg Hanscom
Fuels made from plants, algae, and even garbage may have fallen off the popular radar, but your next airline flight may run on biofuels.

Sometime in the fall of 2015, a United Airlines jet will take off from Los Angeles International Airport bound for San Francisco. The trip, one of a dozen the airline makes daily between LAX and the City by the Bay, will probably seem like any other for the travelers and businesspeople on board, but there will be something quite remarkable about it. It won’t be powered by conventional, petroleum-based jet fuel; instead, the jet’s gas tank will be full of “biofuel” derived from farm waste.

If all goes as planned, it will be one of the first of many passenger flights in the U.S. to run on biofuel—a milestone for a technology that has been touted as a promising solution to both our nation’s dependence on foreign oil and the looming threat of climate change. Depending on the technology, renewable biofuels derived from waste, plants, and algae may reduce the net carbon output to the atmosphere, increase environmental sustainability, address climate change, and lead to other products that can address eye disease and cancer.

The fact that it has taken so long to get to this point, and that we have heard so little about biofuels in the past few years, hints at a larger story, however—one in which economic forces, regulatory loopholes, and years of false starts have hampered the spread of a promising technology. The question now: Could biofuels really begin to take off, or have we turned irrevocably toward other alternatives, like the batteries that power a growing number of vehicles on our streets?

To answer these questions, it helps to jump back to the early aughts, when biofuels were all the rage. Do-it-yourselfers were retrofitting their cars to run on biodiesel. College students and environmental activists crisscrossed the country in buses powered by veggie oil, extolling the virtues of fuel salvaged from deep fryers rather than fracked from the earth or extracted from the seafloor.

Spurred by agribusiness and biotech entrepreneurs, Congress passed a law in 2005 mandating that 7.5 billion gallons of “renewable fuels” be blended into the U.S. fuel supply by 2012, including biofuels made from corn, soy, and other food crops, as well as algae, agricultural waste, and even garbage. In 2007, citing national security concerns, lawmakers increased the mandate to 36 billion gallons by 2022.

Although we haven’t heard much about it since then, this legislation did result in some significant changes.

“Biofuels are still around and we’re using a lot of them,” says Adam Christensen, a postdoctoral researcher with the Johns Hopkins University Whiting School of Engineering who specializes in biofuels.

Today, ethanol derived from corn, which is used as an additive in gasoline, makes up roughly 10 percent of the fuel used for transportation in this country.

We burned roughly 13 billion gallons of the stuff in 2014. Biodiesel, derived from soybeans, recycled vegetable oil, and animal fat, has also gone mainstream. Last year, we used 1.75 billion gallons—thus the distinctive smell of French fries you occasionally catch from a passing truck.

Still, we’re nowhere near where Congress intended us to be. “Thirty-six billion gallons by 2022? You’re never going to see it,” says Christensen.

Blame that, in part, on the Great Recession. Interest in alternative fuels tends to be highest when oil prices go up, explains Deborah Bleviss, administrative director of the Energy, Resource and Environment Program at Johns Hopkins’ Paul H. Nitze School of Advanced International Studies. A lot of companies pursued biofuels early on, only to have their investors turn tail and flee when oil prices dropped in 2009 amid the global financial slump.

While the price of oil has rebounded since then, electric cars have surged into the market, with entrepreneurs like Elon Musk at Tesla claiming some of the space that biofuels might have taken. Electric cars have zero tailpipe emissions, though depending on the source of the electricity, they may still contribute to climate change. Almost 40 percent of U.S. electricity is generated by burning coal; more than a quarter comes from natural gas.

Biofuels, meanwhile, have issues of their own. Proponents of biofuels point out that, unlike fossil fuel—which contain carbon that was captured millennia ago and has been safely sequestered in the ground—biofuels come from plants, which gobble up carbon dioxide as they grow, effectively canceling out the emissions when the fuel is burned. Farming and transporting corn and soy require burning fuel, however, and increasing fuel crop production often requires clearing forests and draining wetlands. The most recent report from the Intergovernmental Panel on Climate Change states that when you factor these things in, biofuels can actually produce more carbon than fossil fuels.

Congress never intended biofuels to be made solely from food crops. Corn ethanol was an easy starting point because U.S. farmers know how to grow corn, and there was off-the-shelf technology to turn it into fuel. 

And then there’s the question of whether all that land would be better used to produce food rather than fuel. In 2013, 40 percent of the U.S. corn crop went to ethanol production instead of food for people or livestock.

But Congress never intended bio fuels to be made solely from food crops, says Christensen. Corn ethanol was an easy starting point because U.S. farmers know how to grow corn, and there was off-the-shelf technology to turn it into fuel. But researchers promised a second generation of “advanced” fuels made from such things as beef tallow, garbage, and algae.

To date, however, no one has been able to make these second-gen fuels pencil out on a commercial scale. A company called KiOR, whose plant in Mississippi generated fuel from wood chips, won the backing of billionaire venture capitalists Vinod Khosla and Bill Gates. But it cost between $5 and $10 a gallon to produce the fuel, according to The Washington Post—a number that did not include the cost of building the plant. The company filed for bankruptcy in November 2014.

The oil giant BP was part of a high-profile effort to create biofuels from corn stalks and other dry, woody plant matter (“lignocellulosic biomass,” in industry parlance) in California, Louisiana, and Florida. The company poured $750 million into the effort before announcing in 2014 that it was pulling out completely and selling its assets.

The 2007 renewable fuel standard, passed by Congress, required a significant portion of new fuels to come from these nonfood sources, but a loophole in the law allows the Environmental Protection Agency to waive that requirement if those fuels fail to materialize. “That has had a cooling effect on second-gen fuels,” Christensen says. “The policy is not sending as strong of a signal to marketplace that investments need to be made.”

There is one place, however, where biofuels are still getting ample attention: aviation.

Petroleum, for all its faults, became popular for a reason, Bleviss points out: “Oil is a fantastic fuel from an energy density perspective.” In other words, you can squeeze a tremendous amount of energy into a small space. You’d be hard-pressed to power a jet with a battery; in order to pack enough punch, it would simply be too big to get off the ground.

No one understands this better than the U.S. military. Back in 2006, as Congress was fiddling with the renewable fuel standards, the military’s research arm—the Defense Advanced Research Projects Agency—contracted with a subsidiary of Honeywell called UOP to produce jet fuel from oil-seed crops such as camelina, a relative of canola. The company, which specializes in oil refinery technology, had developed a process called “fast pyrolysis” capable of producing “drop-in” jet fuel that could be mixed with standard fuel with no retrofitting of the planes themselves.

In July 2012, the Navy conducted a demonstration in the Pacific Ocean off Hawaii of what it dubbed the Great Green Fleet. Made up of planes, including fighter jets, the Great Green Fleet was powered by a 50-50 blend of conventional jet fuel and biofuel. In a press release, the Navy said that “investments in an alternative to foreign sources of fuel will help the Navy and the nation become less dependent on foreign oil and less subject to volatility in oil prices that can directly affect our readiness.”

It’s that price volatility, along with concerns about the outsized climate impacts of air travel, that has inspired the airline industry as a whole to invest in creating a new generation of petroleum substitutes. The fuel that United Airlines plans to use to power that pioneering flight from San Francisco to L.A. this fall is created from inedible animal fat left over from rendering plants and agricultural waste. United is also working with a company called Fulcrum that is building a refinery outside Reno, Nevada, to turn household trash into jet fuel. Fulcrum claims it can cut an airline’s carbon emissions by 80 percent compared with petroleum-based fuel.

Ventures similar to Fulcrum have shifted focus away from biofuels in recent years. Coskata, a Warrenville, Illinois–based company that also had backing from Vinod Khosla, along with a $250 million loan guarantee from the U.S. Department of Agriculture, tried generating fuel from corn husks and municipal trash but switched focus to conventional natural gas in 2012.

Even the United Flight—intended to be the first of many biofuel-powered flights between L.A. and San Francisco—has been beset with delays. The airline originally announced that the program would start this summer, but the launch has been postponed. Company spokespeople declined to say why.

Still, together, the airlines and the military just might create a market big and dependable enough to attract funding for new biofuel ventures. There’s pressure from individual states that have adopted renewable fuel standards of their own. Cities could also act as labs for biofuels, according to Bleviss, if they committed to building the infrastructure. Austin, Texas, did something similar with plugin hybrids, installing charging stations around the city and offering rebates for drivers who bought electric cars and installed home charging stations.

Price volatility, along with concerns about the outsized climate impacts of air travel, has inspired the airline industry as a whole to invest in creating a new generation of petroleum substitutes.

Building a sustainable future for biofuels will require a level of commitment from governments and research institutions that we have not yet seen, says Julian Rosenberg, a former research fellow at the Johns Hopkins University Environment, Energy, Sustainability and Health Institute, whose PhD in chemical and biomolecular engineering focused on the potential use of algae in biofuels.

Rosenberg points to a pioneering effort called the Aquatic Species Program, created by the Department of Energy in 1978 to study how to make biofuel from algae. Researchers looked at thousands of species of algae, identifying the best ones for producing oils and carbohydrates for biofuels. “But as fossil fuel prices came down in the ’90s, the program was dismantled,” says Rosenberg, who now works for a chemical engineering company in Albany, New York.

Today, advances in genetic engineering and genome sciences have made further progress possible—at least two companies have engineered photosynthetic microbes that secrete ethanol directly into the water, Rosenberg says. But in order to make algae-based biofuels economically feasible, more work needs to be done on the basic biology, the technical details of algae farming, and the process of extracting fuel from the microscopic plants.

“It’s technically feasible to produce biofuel from algae,” he says. “The problem is that it’s still very expensive.”

Michael Betenbaugh, a professor of chemical and biomolecular engineering at the Whiting School of Engineering who specializes in microalgae engineering, says that to make biofuels profitable, researchers have turned their attention to “co-products”—that is, processes that produce both biofuels and more lucrative products such as pharmaceuticals and dietary supplements. Researchers use algae as a platform for growing omega-3 fatty acids; betacarotene used to fight certain cancers; lutein, which aids in ocular health; and astaxanthin, an antioxidant that also happens to be the pigment that makes salmon pink.

Rosenberg imagines a day when algae produce oil for biofuel as well as omega-3 for nutritional supplements, pharmaceuticals, pigments, and protein for fish food. “What’s the saying? Use every part of the pig except the oink?” he says. “That would bring together the health of the environment, actual medical therapies, sustainable food, and human nutritional supplements as well.”

It would be the perfect melding of human and environmental well-being.

But, for now, it’s still a dream. “We have some significant technical and scientific hurdles we need to overcome,” Betenbaugh says. In the meantime, bio-fuels are likely to remain at the whim of oil markets and public policymakers.

On the ground, that means that ethanol and biodiesel will still be part of the mix at the gas pump, but more and more, it will be batteries and not biofuels that power our vehicles. Musk, who pioneered the Tesla, is hard at work on a battery capable of powering not just your car but also your home.

In the air, it could be a different story. The EPA announced this summer that it will begin regulating carbon emissions from the airline industry, just as it has from coal-fired power plants. “Airlines are seeing the writing on the wall,” Christensen says, “and they know that it takes a long time to get alternative fuels of the ground.”

Illustration of plane and truck made with vegetables
Illustration by Pierluigi Longo
Renewable biofuels derived from waste, plants, and algae may reduce the net carbon output to the atmosphere, increase environmental sustainability, address climate change, and lead to other products that can address eye disease and cancer.

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