“Man’s battle with nature has been won. Whether we like it or not, we are now burdened with the administration of the conquered territory. Nature reserves, landscapes, townscapes: they will all be wantonly destroyed, to the ultimate ruin of man, or they must be deliberately planned to serve his needs” – Ove Arup, one of the 20th century’s great engineers.
“What’s the use of curing cancer if we destroy the planet?” J. Craig Venter
Air Traffic Control (ATC) improvements provide the easiest short term initiative to dramatically reduce greenhouse emissions from transport aircraft.
Aerospace has always been a technology leader, and together with the air transport industry has taken a lead in the reduction of greenhouse gases. On April 22, 2008, the world’s airlines, airports and major aircraft manufacturers came together to announce a goal of:
Being carbon neutral by 2050.
Expanding to meet the world’s transportation demands without expanding the emission of greenhouse gases.
The announcement was made in Geneva and Washington, D.C.
New technology has the potential to provide:
- Air Traffic Control – a 15% to 20% reduction;
- Airframe and engine advances – 15% to 25% reduction;
- Airport efficiencies – 10% to 15% reduction.
The reductions can be cumulative. They cannot occur overnight and will take time to phase in, but they are feasible. It’s a matter of application rather than research.
Air Traffic Control improvements are the low hanging fruit currently difficult to pick, due to politics in the United States and Europe.
The “carbon neutral” goal will require research and may well need technological breakthroughs that would then also be available to other industries.
Between 2000 and 2006, U.S. airlines reduced fuel burn (and thus greenhouse gas emissions) by 4% while carrying 12% more passengers and 22% more cargo.
Commercial aircraft are 70% more fuel efficient today than they were 40 years ago.
In the United States
Three key points are being stressed by aviation officials and airlines.
U.S. carriers have reduced fuel burn significantly in this decade.
The industry is eagerly exploring alternative fuels.
A “Next Gen” satellite based ATC system is the best way to rapidly enhance aviation’s environmental efficiency.
Air Traffic Control Improvements
In 2007, the airlines spent $40 billion on fuel, of which $9 billion was wasted through delays. That means their greenhouse gas emissions were 22% higher than was necessary (FAA Forecasting Conference, March 2008).
Planes need fuel that does not freeze at high altitudes and which is uniform the world over. As there are some 19,000 turbine powered transports flying around the world, the best solution would be a “drop in” replacement for existing fossil based jet fuel that emits substantially less carbon. This is a major challenge.
Virgin Atlantic has flown a Boeing 747 from London to Amsterdam using 5% coconut oil to demonstrate a bio-fuel that could take high altitude, cold temperatures. But the short flight reportedly used oil from 150,000 coconuts, so there is unlikely to be enough coconut production to fulfill aviation’s fuel needs.
As part of a research project, Airbus has flown an A320 with one of its engines powered by an alternate fuel generated from natural gas and formulated to produce less greenhouse gas.
Continental Airlines with Boeing and GE Aviation has conducted a bio-fuel demonstration flight using one of the airline’s 737 NGs. Boeing has cited algae, babassu nuts, halophyte plants, jatropha plants and switchgrass as possible sources for the fuel, which could comprise as much as 50% of the blend powering one of the 737’s two engines.
Airbus also is working with Honeywell to develop an Auxiliary Power Unit (APU) in the form of a fuel cell which would be powered by hydrogen. The exhaust would be water, which could be used in the aircraft’s sanitary systems. APUs are used to provide ground power for air conditioning and aircraft services, for engine starting, and for emergency systems power in flight.
Ethanol – the currently popular automotive bio-fuel – will not work for aircraft, as it typically freezes at 36,000-ft., which would create a safety problem. Also, ethanol competes for corn as a source of food, and according to some reports, consumes more energy in its production than it saves as an alternative fuel.
Airbus and Honeywell International, Inc. recently announced their plans to develop a bio-fuel “that by 2030 could satisfy nearly one-third of the worldwide demand from commercial aircraft without affecting food supplies.” According to the Wall Street Journal, they plan to produce fuel from vegetation and algae-based oils that do not compete with existing food production or land and water resources. The Airbus/Honeywell team includes JetBlue and International Aero Engines – largely a partnership between Pratt and Whitney and Rolls-Royce – and other companies. According to Airbus, each company will invest time and intellectual property into developing and testing a bio-fuel “that can later be sold to refiners or others interested in producing it.” “In order to replace a significant portion of jet fuel with bio-jet, we need to find something that has much greater yield than the current bio-mass sources available,” according Sebastian Remy, head of alternative fuels research programs for Airbus.
Honeywell also was selected by DARPA (Defense Advanced Research Projects Agency) last June to develop and commercialize the production of jet fuel from the same renewable sources for use by U.S. and NATO military aircraft.
Airbus and Honeywell recently announced their plans to develop a bio-fuel
The Promise of Bio-fuels
While it’s technically feasible to power aircraft with bio-fuels today, some technical breakthroughs will be required before bio-fuels can be produced in the quantities required to meet the needs of world aviation, i.e. a breakthrough similar to the enzyme discovered several decades ago that enables soybeans to be turned into protein rich food digestible by humans.
All the aircraft and engine manufacturers have research programs underway in order to improve the efficiency of their products. For example, Airbus UK recently launched a Next Generation composite wing project. The program will not only look at wing and aircraft design, but also will examine how to reduce the overall environmental impact of the manufacturing process and the factory. The program provides a fundamental opportunity to re-examine the configuration of commercial aircraft in order to meet the increasingly intertwined issues of environmental impact and fuel burn, Aviation Week reports. Boeing has a similar program underway.
A Boeing research center in Spain has successfully flown the first fuel cell powered aircraft.
United States Air Force Initiatives
The United States Air Force plans to buy 50% of its fuel from synthetic domestic sources by 2016.
Currently, the U.S. military is 1.5% of U.S. fuel use, and consumes 340,000 barrels of oil a day.
The Air Force goal is to:
- Reduce its dependency on foreign oil.
- Stimulate large scale commercial production of synthetic fuels.
“Our goal is to drive the development of a market here in the U.S.” Air Force Assistant Secretary, William Anderson, told the Wall Street Journal.
The Air Force is working with aircraft and engine manufacturers, such as Boeing and Pratt and Whitney. North American synthetic fuel producers include Rentech, Inc., Baard Energy, and Syntroleum Corporation. All operate or hope to build synthetic fuel refineries to feed the military’s growing thirst, the Wall Street Journal reports.
Synthetic fuel, according to the Wall Street Journal, which can be made from coal or natural gas, could cost far less than oil at its current price (about $130/barrel), if the synthetic is mass produced.
South African Airways has been using a similar blend of half synthetic/half conventional fuel in its commercial aircraft for years.
The Air Force has now tested its alternative fuel in a B-52 bomber, in a C-17 transport, and in a B-1 bomber flying at supersonic speed.
The process for turning raw carbon sources, such as coal or natural gas, into usable aviation fuel was developed by German scientists in the 1920s.
Alternative fuel has been tested in a B-52 bomber
Air Transport Association (ATA)
Federal Aviation Administration (FAA)
 Even with the planned cutbacks, the U.S. carriers’ fuel bill is expected to exceed $60 billion in 2008.