Use of biofuels growing in global aviation.
Indeed, 2008 and 2009 saw a number of successful biofuel test flights around the world and despite the economic downturn restricting budgets, companies within aviation remain committed to seeking greener fuel alternatives.
But how realistic is the airline industry's switch to biofuel? And will green fuels become mainstream within civil aviation in the future?
"With energy demand and environmental concerns growing, diversifying the current fuel supply is very important," said Susan Gross from UOP Communications (www.uop.com), a company at the forefront of renewable energy solutions. She added, "We believe that commercial use of renewable jet fuel is possible by as early as 2012."
Elizabeth Merida from the US-based Air Transport Association (ATA) (www.airlines.org) has a similar forecast. ATA is a founding member of the Commercial Aviation Alternative Fuels Initiative (CAAFI), a consortium of airlines, airports, government, fuel suppliers, and other alternative aviation fuel stakeholders in America. "Through CAAFI, the industry is striving to have biofuels certified for commercial aviation use between 2010 and 2013," she stressed. Ms Merida's predictions are based on biofuels accompanying jet fuels, rather than replacing them. "We believe biofuels will become commercially available in sufficient quantities for blending with traditional jet fuels as early as 2013."
The International Air Transport Association (IATA), which represents 230 airlines, approximately 93% of the world's airline traffic, is eager for biofuels to gain certification and has been working with regulators to have biofuels in commercial aviation use by 2010 or 2011--originally the group had predicted 2013.
Despite the positive outlook from these important aviation organisations, these comparatively sustainable plant-based fuels still look set to only account for a small portion of total jet fuel consumption.
Aircraft manufacturer Airbus believes that biofuels will account for about 25% of all commercial aircraft fuel in use by 2025. Boeing also has reserved predictions: "Aviation will likely not be a major market for biofuels, but it may well serve as a catalyst for moving their availability forward within the transportation sector," said Terrance Scott from Boeing.
Virgin Atlantic took the first partial biofuel test flight on February 23, 2008. This initial flight used a 20% mixture of coconut and babassu oil (mixed with 80% conventional jet fuel) in one of its four engine tanks. The passenger-free flight was thought to be a publicity stunt by some. Regardless of whether it was or not it did help pave the way for other tests among airline companies around the globe. The testers who followed Virgin chose to look at the eco-impact of biofuels at all phases of the fuels lifecycle and decided upon more sustainable plant options, taking account of the available feedstocks. The biofuel trials that occurred after the first test also involved an increased plant-based portion, creating a 50:50 biofuel and conventional jet fuel mixture.
Through mixing plant-based fuel with traditional fuels, the resulting liquid works with the current equipment--overcoming the cost barrier biofuels would face if the system needed to be updated for adoption.
"Biofuels must be drop-in replacements for petroleum-based fuels and must perform as well or better than their petroleum based alternatives," explained Ms Gross. "This means that they can be blended with existing fuel and can utilise all of the existing infrastructure and fleet technology available today." She added: "If the fuels are not drop-in significant capital costs will be required for adoption."
Driving biofuels growth is the rising concern over the airline industry's carbon footprint, along with the industry wanting to move away from the price volatility it experiences with petroleum. "In terms of cost, there may not be a competitive advantage (for biofuels)," said Ms Merida. "That remains to be seen. Obviously the economies of biofuels will evolve depending upon the construct of any future regulatory schemes."
In terms of aviation's eco-impact the airline industry has taken active measures to reduce carbon emissions for a number of years. In spite of this they continue to be scrutinised due to the high visibility of airline travel and cheaper flights leading to an increased number of journeys. Since 1997 Continental Airlines has reduced their fuel consumption and carbon emissions by 35% per passenger mile flown. Other airlines have followed a similar path with the industry overall reporting a 70% improvement in fuel-efficiency and CO2 emissions per passenger mile in the last 50 years, according to aviation specialist publication www.aviation.com. These efforts are just the start and biofuels looks set to dramatically lessen aviation's eco-impact--if the new fuel sources can meet industry standards.
"Jet fuel from sustainable biomass sources have the potential to reduce greenhouse gas emissions (from planes) by upwards of 60% as compared to jet fuels from petroleum," said Mr Scott. Boeing's figures look at the entire lifecycle?taking into account the plants used for fuel absorbing CO2 as they grow.
Ms Merida also noted the "entire lifecycle" approach. "Carbon emissions measured from aircraft engines likely will not be significantly different when biofuels are used than when traditional jet fuel is used," she said. "That is because jet engines require a certain amount of energy which is carbon-based. The significant carbon benefits of biofuels are realised earlier in the fuel production chain than with traditional fuels. Specifically, bio-feedstocks pull carbon out of the air as they are grown."
First generation biofuels, sourced from food items such as corn and soybeans, underwent scrutiny as their production competed with food supply. Boeing predicted that growing enough corn or soybeans (used for first-generation ethanol) to power all the world's airliners would have required an area about the size of the United States (see--Biofuels Become Aviation's Big Focus, June 26, 2008, www.aviation.com). Second and third generation natural blends, including jatropha, camelina, and algae (a third generation fuel) have been used in varying percentages in the majority of tests undertaken within the aviation industry.
These new-generation alternatives will offer the air industry advantages as anti-global warming agreements start to bite worldwide, with life-time emissions assessments becoming the norm. Second-generation jatropha biofuel was used in Air New Zealand's alternative fuel test flight on December 30, 2008. Looking at the overall impact fuel has, Air New Zealand sourced jatropha grown on sustainable farms within Malawi, Mozambique, Tanzania, and India. The seeds were grown on non-arable land so fuel production did not take up land that could otherwise be used for food crops. One of the criteria for Air New Zealand was that "the land was neither forest land or virgin grassland within the past two decades.... the land was not suitable for the vast majority of food crops." The smooth two-hour test flight used a 50:50 fossil and biofuel mix in one engine of a Boeing 747 and was deemed a success.
At this year's Aviation & Environment Summit in Geneva (www.envirosummit.aero), express delivery service TNT's chief executive officer Peter Baker (http://group.tnt.com) committed to planting 24 million jatropha plants in 2009, and an additional 250 million by 2014. The project is two-fold, helping to alleviate poverty through creating jobs in Africa, as well as increase the availability of biofuels--a barrier to adoption.
Biofuel production hopes are high for the future but long-term availability still remains an issue. British Airways had to pull out of a planned test flight this year due to lack of accessibility of biofuels. British Airways and Rolls Royce were looking for a long-term commitment from a biofuel supplier?one that could commit to supplying 60,000 litres and prove that production was sustainable with "no detrimental impact to food, land, or water." The tender, released in July 2008, only had one suitable candidate at the time submissions closed. As a result they extended the date in the hope more applicants will come forward.
Camelina and halophytes are two other promising second-generation options that have been successfully trialled. Japan Airlines (JAL) took flight with a camelina and fossil-fuel blend, also in a 747, on January 30, 2009. The pilot reported no difference in performance in the biofuel mix compared to standard jet fuel, and those involved in the testing were pleased with the initial results. The 50% feedstock for the bio mix included 84% camelina, under 16% jatropha, and less than 1% algae in one of the plane's engines.
Algae may have only accounted for a miniscule portion of the JAL flight, and a small portion of other tests, but looking forward the well-known seaweed is touted as the most feasible biofuel option.
Compared to first-generation, and even second-generation, the space required to use algae to fuel the whole world's airplanes would only amount to an area the size of West Virginia, according to www.aviation.com. One acre of algae would make enough oil for 3,000 gallons (11,356 litres) of jet fuel in one year. It also has the added benefit that it can be produced in salt-water tanks anywhere--further reducing competition for land use.
Sapphire Energy (www.sapphireenergy.com), an American-based leader in renewable sustainable fuels, has big plans for the mass production of algae biofuels. The company predicts that by 2011 they will be producing one million gallons (3.8 million litres) of renewable algae based fuel. By 2018 the number is expected to reach an annual amount of 100 million gallons (380 million litres).
Algae was effectively used in a test flight earlier this year: the USA's Continental airlines used a 6% algae, 44% jatropha, and 50% traditional jet fuel mix in one engine of a Boeing 737 for their test flight over North America. "We decided to use a 50:50 blend of biofuel in order to be consistent with other alternative fuels that are in the process of applying for ASTM certification," explained Anna Chan on behalf of Continental. "She also added. "A 50:50 blend builds on the blend percentage (20% biofuel, 80% jet A) that was used during the industry's initial biofuel test flight."
Continental's passenger-free flight on January 7, 2009, further proved that biofuels work well as a drop-in replacement. During the two-hour assessment, the plane was put through a number of tests including mid-flight engine shutdown and restart, and accelerations and decelerations. The flight data was recorded, as it has been with other similar test flights, and is ready for analysis. "Our (CAAFI) industry partners and researchers tell us that they have a tremendous amount of data from the succession of flights over the past year, so lab work on the data and emphasis on demonstrating that alternative fuels meet the jet fuel specifications are likely to be the greater focus over the coming months," said Ms Merida.
Although all test flights to date have been successful based on surface tests (whether it worked well based on pilots' feedback and its ability to pass standard testing covering what could and does happen during a flight) there is a lot of work that needs to be done behind the scenes. This new-breed of fuels must meet standards set by the USA's Federal Aviation Administration (FAA) including the ASTM D1655 standard (www.astm.org), a specification set for aviation turbine fuels. "The performance characteristics of alternative jet fuel must be equivalent to those of conventional jet fuel at every stage of distribution, delivery, storage, and utilization in the aircraft and its engines," said Ms Merida. Ms Merida also mentioned that equivalency is required in: lubricity, seal swell, dielectric constant, density, bulk modulus, water solubility, viscosity, thermal conductivity, specific heat, auto-ignition temperature, hot surface ignition temperature, toxicity, and storage stability.
The second half of 2009 and early 2010 may see some more biofuel experimentation in the skies, but the bulk of work from here on in will be behind the scenes. The major companies and consortiums involved must ensure second and third generation biofuels meet all the necessary standards in order to reach their deadline of creating a cleaner, greener sky within the next few years.
|Printer friendly Cite/link Email Feedback|
|Publication:||International News Services.com|
|Date:||Apr 1, 2009|
|Previous Article:||International sanctions compliance is major challenge for financial institutions and corporations.|
|Next Article:||EU pushes ahead with biofuel promotion plans--but green issues make policy complicated.|