Aviation Alternatives

January 1, 2009

BY Jerry W. Kram

Algae has long-held the imagination of alternative fuel advocates. Promises of thousands of gallons of oil per acre of land created out of nothing but carbon dioxide and sunshine caught the attention of entrepreneurs and investors. But alas, reality is a cruel mistress and while the dream and potential of algae are still real, the practical realities of growing and harvesting millions of pounds of photosynthetic microorganisms have proven to be formidable. Dozens and possibly hundreds of companies have been working on a practical algae production system over the past several years. But, as yet, no company is selling commercial quantities of algae oil.

The algae industry is not so much in its infancy as still developing in the womb. A bright spot in the algae picture is that industries with burgeoning fuel bills have become interested is assisting with the birth. In particular, aviation companies have identified algae as a potential fuel source for their fleets. Airlines such as KLM/Northwest and Virgin Atlantic and manufacturers such as Boeing are working to support algae producers and bring the technology to a point where it can support their fuel needs.

For the airlines, the advantages of algae are significant. Fuel is a major component of their business costs. Aviation uses 5 percent of the world's fuel and is responsible for 2 percent of global greenhouse gas emissions. Finding an alternative feedstock is important to the long-term stability of the industry. A second reason for their support is a growing emphasis on using sustainable fuels in the airline industry. A spokesman for Virgin Atlantic says biofuels are a solution for the aviation industry to cut carbon emissions and preserve the environment. "About three years ago, we started to see some things happening on the fuel technology front that caught our attention," says Bill Glover, Boeing's managing director of environmental strategy. "We thought we should start looking into that. Our motivation was the price of fuel and also interest in finding ways to lower the environmental footprint of aviation." Virgin, Boeing and a number of other leading aviation companies formed the Sustainable Aviation Fuel Users Group. The group's members represent about 15 percent of the world's aviation fuel consumption. "SAFUG is focused on establishing the sustainability criteria, such as life-cycle assessments, so we have a fact base to avoid the kinds of problems that have crept into early biofuels development," Glover says. "We don't want to be competing with food uses and that sort of thing. We want to understand that and avoid problems from the start."

Partnering for Progress
SAFUG is partnering with the Natural Resources Defense Council and the World Wildlife Fund to develop its sustainability criteria. The group has announced two initial sustainability research projects. Assistant Professor Rob Bailis of Yale University's School of Forestry and Environmental Studies will conduct the first peer-reviewed, comprehensive sustainability assessment of jatropha to include life cycle carbon dioxide emissions and the socio-economic impacts on farmers in developing nations. Similarly, NRDC will conduct a comprehensive assessment of algae to ensure it meets the group's stringent sustainability criteria. "This is a tremendous opportunity for leading airlines, supported by well-respected energy and environmental organizations, to help commercial aviation take control of its future fuel supply in terms of origin, sustainability and environmental impacts," Glover says. "The No. 1 priority going forward is to complete thorough assessments of sustainable plant sources, harvesting and economic impacts, and processing technologies that can help achieve that goal."

Glover says the NRDC and WWF have a long history of working with industries to improve their environmental profiles. "These groups had established relationships with some of our members," he says. "They were a known quantity and were willing to have a constructive dialogue about establishing the facts. It's a good relationship based on common interests in reducing the industry's environmental footprint in a way that has positive attributes for all the parties concerned."

Each member of SAFUG has signed a document committing it to "advance the development, certification, and commercial use of drop-in sustainable aviation fuels." Drop-in fuels are those which can be substituted for commercial aviation fuels with no changes to the fuel transportation, storage and dispensing infrastructure or to the planes. The document also defines what the group believes to be sustainable standards. The fuel should not compete with food crops, cause disruptive land-use changes or jeopardize water supplies. A sustainable fuel will have significantly lower life-cycle greenhouse gas emissions than petroleum-based fuels. In developing economies, alternative fuel projects should improve the socio-economic well-being for local people, including subsistence farmers. Finally, an alternative fuel should not cause high-value conservation areas and native ecosystems to be cleared for agricultural production.

The aviation industry is by nature conservative in changing key components of the industry in order to preserve its passenger's safety. However, the push to develop an alternative fuel for commercial aviation has taken root rather quickly by industry standards. "We are a pretty complex industry and necessarily conservative because we want to make sure we are reliable in serving the public," Glover says. "This is actually moving very fast from our industry perspective. We are very excited about that."

Test Flights Take Off
Finding a fuel that will work properly with jet engines is a key priority for the safety conscious aviation industry. In February 2008, a Virgin Atlantic jet was the first to fly on a mixture of biobased fuel and kerosene. That test using fuel derived from coconuts and a palm called babassu was the first of four planned by SAFUG. "We found no show-stoppers in the Virgin Atlantic test," Glover says. "It wasn't perfect and the fuel will probably not be the mix that will be commercialized, but it gave us the stepping stone toward more interesting possibilities. It gave people confidence and verified that we can do this. That was a big hurdle."

An Air New Zealand jet fueled with jatropha-based aviation fuel was scheduled to take flight before the end of 2008. The other tests will be carried out by Continental Airlines and Japan Airlines. "Each flight will test a different feedstock as a source of the fuel," Glover says. "There are also four main aircraft engine manufacturers serving commercial aviation and we wanted to make sure they were all engaged. We want to understand the technical viability and the economic viability, and see what we need to do to facilitate the commercial reality. That's where we want to head."

Because aviation is a worldwide industry, and alternative fuel feedstocks are likely to vary widely from country to country, the industry will need fuel specifications that will be workable in many different situations. "The key to that will be to specify the performance you need and the things you cannot have as constituents," Glover says. "There are certain compounds that can do damage when used long term in an engine or an airframe. So you want to screen for those things. But other than that we will basically have a performance-based specification."

SAFUG identified algae as a feedstock of interest because it has the potential for producing large amounts of fuel. Algae is thought to be capable of producing 10 to 20 times as much vegetable oil per acre as agricultural crops such as soybeans or even palm oil, the most productive traditional source of oil. "You can get a lot of plant oil in a fairly short amount of time," Glover says. "If the yield estimates are as good as they look at this point, a fairly small amount of land would be necessary."

The problem with algae is that as an industry, it is still in the process of being born. While a large number of companies are working on developing systems to grow algae for biofuels, none are close to commercial production. Boeing and Airbus, the two largest aircraft manufactures are sponsors of the Algae Biomass Organization, a trade group for companies in the nascent industry. "We are in the very early stages of an industry with huge potential," Glover says. "We are trying to establish the industry's trajectory. The Algae Biomass Organization is set up to facilitate the establishment of the industry and network the people working in it to accelerate the development of the industry." He added that along with education and networking, the organization will also be an advocate for public policies that will support the algae industry.

While the road to sustainable algae-based aviation fuels is long, the airline industry is pushing to adopt sustainable biobased fuels quickly. Virgin Atlantic wants to replace 5 percent of its fuel with sustainable biofuels by 2015 and increase that to 10 percent by 2020. "In five years, certainly, we will see commercially available sustainable biofuels for aviation," Glover says. "It may be sooner than that. We have beaten all our estimates so far. But I think that's a fair assessment at this point. There is a lot of uncertainty, but I think it is quite likely that it will be within five years."

Turning algae oil into jet fuel is not as straightforward as making biodiesel, says Joseph Kocal, director of renewables research with UOP, a division of Honeywell Inc. To make a truly drop-in fuel replacement, the fatty acids in the oil must be chemically transformed into paraffins to make a fuel that matches the ASTM 1655 standard for aviation fuel. Kocal says the first step was to remove the oxygen from the fatty acids, leaving long-chain hydrocarbons. For nearly all feedstocks, the hydrocarbons need to be shortened to produce compounds that will vaporize in the proper temperature range. Finally, the hydrocarbons go through a cracking process to isomerize them into branched molecules that won't gel at the low temperatures found at high altitudes. The fuel will still need additional aromatic hydrocarbons to meet the ASTM specification. Kocal says these compounds could be manufactured from biomass in the future using pyrolysis. Most of the technology needed to produce jet fuel from algae oil is commonly used in the petrochemical industry. "The cost of making this fuel should be well in line with petroleum production costs if we can keep feedstock costs low," he says.

Jerry W. Kram is a Biodiesel Magazine staff writer. Reach him at jkram@bbiinternational.com or (701) 738-4920.

Advertisement

Advertisement

Upcoming Events

Sign up for our e-newsletter!

Advertisement

Advertisement