According to the International Air Transport Association, the aviation industry is responsible for nearly two percent of all man-made carbon dioxide emissions. As a result, second-generation biofuels — such as those made from algae and other forms of biomass — are more often being considered by the aviation industry as appealing alternative fuel source. With cap-and-trade legislation looming, airlines continue to look for new ways to decrease their CO2 emissions and trim costs. And algae fuel is factoring into the solutions for alternative fuel sources in a big way.

In July, ASTM International — the organization that sets technical standards, including those for aviation fuels — granted commercial carriers approval to use fuel mixtures that contain up to 50 percent biofuel. Under the Specification for Aviation Turbine Fuel Containing Synthesized Carbons standard (or D7566, as it’s known in the industry), several national and international carriers spent months testing flights powered by biofuels. In August, AeroMexico conducted the first biofuel-powered transcontinental commercial flight. Pretty cool, huh?

Why fuel from algae? Why now?

The concept of using algae to produce fuel is nothing new, so why the renewed interest in algae versus other biofuel sources? Why not? For starters, some algae strains can be used to produce high-octane fuel blends that resemble petroleum-based jet fuel. But algae don’t compete with valuable land resources like other renewable fuel sources, such as ethanol, which is made from corn. Growing algae requires sunlight and carbon dioxide, so it also presents opportunities for sequestering CO2 from some of the largest emitters — like fossil-fueled power plants.

Additionally, concerns about rising fuel prices and increased pressure to reduce fuel emissions make it a perfect time to explore and implement this option. One executive at Honeywell’s UOP says biofuels can reduce net carbon emissions by as much as 85 percent compared to traditional petroleum-based fuels.

Some challenges

Currently the cost of producing biofuel is high — three to five times more than traditional jet fuel, which already makes up airlines’ biggest cost. Analysts expect the cost to drop as production and demand increase. But it’s difficult to produce a competitively priced product that doesn’t lose its environmental benefits due to the amount of energy required to make it — especially considering the amount of biofuel it takes to power aircraft. And although algae can grow on undesirable land, growing enough algae to produce substantial amounts of fuel requires large amounts of surface area and water.

What’s next?

Moving toward biofuels can help the industry achieve its goal of being “carbon neutral” by 2020. In other words, the hope is to maintain its carbon emission levels while continuing to grow business. Plane-makers Airbus SAS and Boeing estimate that by 2030, plant-based fuels could account for as much as 30 percent of aviation use. And with 98 percent of the U.S. Air Force fleet equipped to run on biofuel blends, the military is also exploring the use of algae-based biofuel.

Want to learn more? Check out The Beginner’s Guide to Aviation Biofuels.