Boeing imagines future network of decentralised biofuel producers

Increasing air traffic is the ultimate symbol of the world's rapid globalisation. Large jets take thousands of people to the other side of the planet in a matter of hours, fill up their tanks at the airport and carry on to their next destination. Non-stop. One factor that has made this revolution possible is the availability of inexpensive, standardized jet-fuel, made from petroleum. The fuel is the same in Singapore and Boston, in Rio de Janeiro and in Brussels.

However, if it is up to Boeing, this will soon change. The aiframer imagines a world in which there are thousands of independent biofuel producers each making their own fuel from the most efficient local feedstocks and to a common global standard. Boeing's biofuel strategy has greatly expanded and is moving in this direction as the company prepares to select a specific biofuel source for two demonstration flights scheduled next year.

A series of laboratory tests completed by Boeing in the third quarter of this year confirmed that biofuels for large aircraft can be practically derived from far more feedstocks than previously believed, says Bill Glover, Boeing's director of environmental strategy. Glover wrote the report titled 'Alternate Fuels for use in Commercial Aircraft' [*.pdf] in which different biofuel production pathways for aviation fuels are explored. Boeing's lab tests showed that a variety of feedstocks can produce biofuels with kerosene-like freezing characteristics. Boeing also now believes a number of such biofuels can be affordably mass-produced for the aviation industry.

Distributed network
These findings have widened Boeing's vision for the future use of biofuel by airlines. Instead of a single, huge repository of biofuel feedstock to supply the world's airlines, Boeing envisions the growth of a distributed network with multiple feedstocks harvested for biofuel around the world, says Glover. The shift in strategy may have serious implications for the future of the energy industry. Glover likens the change to the way personal computers overtook mainframes about 20 years ago:
energy :: sustainability :: biomass :: bioenergy :: biofuels :: distributed :: decentralisation :: aviation :: jet fuel ::

Industrial energy production may shift from monolithic producers of petroleum to a distributed network of biofuel providers, each cultivating the feedstock most appropriate for its geography and climate, he says. Each biofuel type will be produced to meet the industry's current fuel standard, he adds. So an airliner fuelled by one feedstock type can be refuelled by another biofuel source.

Boeing believes its role will be to serve as a catalyst for a distributed biofuel production system that it sees emerging within the next five years. Unlike an airline, Boeing does not buy fuel in bulk, but it may be able to provide other means of financing and technical support.

The first step is to prove the feasibility of biofuel-powered commercial aircraft. Boeing has teamed with Virgin Atlantic to test a General Electric-powered 747 (more here) and with Air New Zealand to test a Rolls-Royce-powered 747 (earlier post).

The flight-test programme is likely to consist of a single flight and consume a total of about 3,800 litres (1,000 gallons) of biofuel, says Glover. The company is close to selecting a feedstock for the flight-test programme, but Glover emphasises that this biofuel type is for demonstration purposes only.


Research into bio-jet fuels has exploded over the past years, partly because airlines' profitability strongly depends on fuel costs and because bio-jet fuels promise to reduce emissions considerably. But biofuels for aviation present several challenges: they require high-performance characteristics, in particular the capacity to remain fluid at low temperatures and the need for smooth blending with petroleum based fuels. Gradually, biofuels are being designed that approach the required cold tolerance threshold.

Likely candidates are synthetic biofuels, obtained from gasifying biomass that is liquefied by Fischer-Tropsch synthesis ('biomass-to-liquids'). Such fuels can be refined into designer fuels with specific characteristics. Another potential fuel is 'green diesel' based on a hydrogenation process of vegetable oils.

Some recent initiatives in bio-jet fuel research include a large program by the French aerospace industry into second-generation (synthetic) biofuels and other candidates. The project, known as CALIN is being initiated by a conglomerate of research organisations consisting of France's aerospace research agency ONERA, propulsion company Snecma and members of the country's Aerospace Valley group which unites most of Europe's leading aerospace manufacturers, including EADS, Airbus, Air France Industries, Alstom and Dassault (earlier post).

Snecma recently succeeded in testing a CFM56-7B jet engine with an ester-based biofuel at a Snecma site in Villaroche. The engine is produced by a joint venture between Snecma, CFM International, and General Electric Company. The fuel used was a methylester derived from plant oil, mixed with 70% Jet-A1 kerosene. The successful test with the unmodified engine reduced carbon dioxide emissions by 20% (earlier post and here).

A large number of private initiatives are underway to develop biokerosene. Amongst them Diversified Energy which developed biofuels that withstand very cold temperatures and can be used in aviation. Their process consists of freeing up the free fatty acids contained in triglycerides from glycerol and passing them through a catalyst after which a resulting gas is synthesized into a liquid (earlier post)

UOP, a Honeywell company, has accelerated research and development on renewable energy technology to convert vegetable oils to military jet fuels. UOP developed a technique based on hydroprocessing that may yield fuels that meet the stringent requirements (more here).

The University of North Dakota recently received a US$5 million grant to develop military bio-jet fuels (earlier post). Whereas North Carolina State University found an innovative technology for the production of biofuels for jet aircraft based on transforming glycerol, the major byproduct of biodiesel (earlier post).

Obviously, several armies are looking into biofuels for aviation as well. A study for the US Military, written by Sasol, concluded that synthetic biofuels (Fischer-Tropsch) can power the entire military - including its airforce - in case of severe oil supply disruptions (earlier post). Finally, the U.S. Air Force has been experimenting extensively with synthetic fuels, which can be made from biomass. It already ground-tested them in real engines (earlier post).

Brazil's state-owned Petrobras announced it plans to introduce a type of bio-jet fuel named 'Bio QAV' in 120 of the country's airports, with concrete trials to begin in 2008. 'Bio QAV' ('Biokerosene for Aviation') is based on the H-bio second-generation biodiesel production process, which relies on hydrotreating vegetable oils (more here).

And most recently, the US Airforce made the first ever transcontinental flight of a C-17 on synthetic fuels, which can be made from biomass (previous post).

References:
FlightGlobal: Boeing expands biofuel strategy - December 20, 2007.

David L. Daggett, Robert C. Hendricks, Rainer Walther, Edwin Corporan, "Alternate Fuels for use in Commercial Aircraft" [*.pdf], Boeing, 2007.

Biopact: Virgin Atlantic to test biofuel in 747 in early 2008 - October 16, 2007

Biopact: Boeing, Air New Zealand and Rolls-Royce to conduct biofuel flight demonstration - September 28, 2007