Is Greener Air Travel on the Horizon?

Technological progress is impossible to predict, but it's safe bet that we won't be flying solar- or wind-powered airplanes anytime soon. So the best hope of flying without emitting large volumes of greenhouse gases lies with biofuels.

This week, there's good news on bringing biofuels in the air. Beginning Wednesday, Alaska Airlines will fly 75 commercial passenger flights in the U.S. powered in part by biofuels. "This is a historic week for aviation," declared Alaska Air's CEO, Bill Ayer, in a press release. Today (Nov. 7), United Airlines make the first U.S. commercial flight using an advanced biofuel made from algae, according to Reuters.

Keith Loveless, vice president of corporate and legal affairs, who oversees sustainability, told me: "These fuels will make a meaningful contribution towards reducing the aviation industry's environmental impact, and towards reducing fuel volatility, which is an incredible problem for the airline industry."

But -- and you knew there would be a but -- biofuels remain way too expensive to replace jet fuels today. That's why Tom Vilsack, the agriculture secretary, got on the phone with me last week so that the Obama administration will do all it can to advance progress on aviation biofuels. "We are engaged right now in aggressively promoting research to determine the most efficient non-food feed crop that can be used," he said.

Biofuels remain controversial, of course. The U.S. Senate, in a symbolic vote, overwhelmingly expressed support last summer for an end to massive corn ethanol subsidies, in what the NRDC's Nathanael Greene called "a victory for taxpayers and the environment."

But both the industry and environmentalists say that biofuels for aviation make sense. That's because the only practical way to dramatically reduce CO2 emissions from planes (other than grounding them) is with biofuels. Plant-based jet fuels emits as much carbon pollution as traditional, petroleum-based jet fuel -- indeed, they are chemically almost indistinguishable -- growing new plants recaptures those CO2 emissions.

And airplanes matter. Aviation accounts for about 1.5 percent of global man-made GHG emissions per year, and gains in aircraft efficiency have been entirely offset by growing demand for air travel, according to the Pew Center on Global Climate Change.

The industry supports biofuels for business as well as environmental reasons, Loveless told me. Creating an alternative to traditional get fuel will increase supply, drive down costs and reduce price volatility. "We are probably more affected by the price of fuel than any other industry," he said.