Higher frontier
The competition to be the first to market with sustainable alternative fuels is in full motion, but sometimes the hype threatens to obscure the real challenges ahead
The race to dominate future alternative fuel technologies bears all the hallmarks of the age-old tussle of truth versus spin. The public relations imperative seems to be becoming more about targeting popular opinion than communicating the difficulties involved in finding a genuine alternative to the principal greenhouse gas villain, kerosene.
So it was somehow fitting that Rainer Ohler, Airbus's head of communications, welcomed journalists to the 1 February launch at Filton, UK, of its first airliner flight test powered by gas-to-liquid (GTL).
It was, he said, an important day for international collaboration and co-operation on research and development, the beginning of a journey at the end of which Airbus and its partners, Rolls-Royce and Shell, would lead the mission to find a sustainable solution in which a third of the global airliner fleet could possibly operate on biofuel by 2030.
Second generation
Sébastian Rémy, Airbus's head of alternative fuels research programmes, then proceeded to outline how the first-ever commercial airliner flight with GTL was the first step of the airframer's lengthy journey towards an ultimate future of second-generation biofuels, that is, aviation fuels produced from renewable and sustainable biomass feedstocks.
Airbus's idea to develop GTL with Qatar and its vast natural gas reserves was trailed at the Dubai air show in November. But any far-sighted vision that Airbus was developing soon came under acute pressure from the 14 January headline-grabbing announcement by UK airline Virgin Atlantic that it too was on the verge of conducting a February demonstration flight between London Heathrow and Amsterdam aided by Boeing and GE Aviation. Only this time, it would be using a "truly sustainable" biofuel that it claimed had no impact on fresh water or land resources.
The precise choice of the alternative fuel is assuming great importance in these early trials even though most fuel experts say that they do little more than demonstrate proof of concept.
An alternative fuel is judged to be any alternative to conventional oil-derived kerosene. This can include both biofuel, which technically is any fuel produced from biomass regardless of the process and synthetic fuels produced via the Fischer-Tropsch method which includes coal-to-liquid (CTL), gas-to-liquid (GTL) and biomass-to-liquid (BTL). The carbon dioxide footprint of each of their respective lifecycle characteristics do however vary widely.
Rémy depicts a future where global energy demand could more than double by 2050. "Hydrocarbons will continue to provide the foundation for the energy supply for the rest of this century but certainly due to this increased demand it is pretty obvious that the age of "easy oil" is over," he says. "There will be competition, there will be more demand for oil and the consequence will be the management of environmental impact of that energy demand."
Rémy adds that taking future demand into account, it would be sensible to look at aviation alternatives not only for economic reasons but to meet aviation's corporate citizenship commitments to keep its environmental impact at a minimum.
And therein lies the transatlantic rub, with Airbus and Boeing both vying to occupy the moral high ground, accompanied with not only a fair amount of publicity but also ambitious to set the fuel standard.
Within Airbus's chosen arena, BTL promises far better environmental credentials because the carbon dioxide absorbed during the growing period offsets CO2 emissions when the fuel is burned. GTL has the same CO2 lifecycle as conventional jet fuel although it scores high in local air quality terms due to no sulphur and reduced particulate emissions.
"GTL therefore is a good contender for the near term and BTL is even a better contender in the longer term once the biomass availability issues have been resolved," says Rémy.
Two other contenders are also proposed - albeit with reservations. Hydrogenated vegetable oil with fuel characteristics similar to convention jet fuel will, however, depend on biomass availability, while cryogenic fuels - liquefied natural gas and hydrogen - will, arguably, require a revolution of both the existing fuel due to its low energy content and conventional airframe infrastructure.
Lifecycle analysis
Paul Bogers, aviation technology manager at Shell, reports that comprehensive "well-to-wake" full lifecycle analyses are conducted as routine for all biofuel propositions, which includes growing processes, farming intensity, use of land and water through to the pathway or the process to turn it into fuel, in addition to the CO2 characteristics of the end product when burnt. Analyses of cost also feature highly in any assessment.
"Second-generation biofuels do encompass a much wider range of options: biomass or other feedstocks that could produce alternative fuels," he says, adding that from an aviation perspective some exciting processes exist through exploiting renewable and sustainable potential feedstocks such as lignocellulose, starched, sugars, jatropha and algae.
Rémy, however, says the availability of significant quantities of GTL in the short-term through Qatar's Pearl processing plant that comes on-stream in 2011 means the industry can gain experience with synthetic fuels before transitioning seamlessly to BTL, once issues of sustainability are resolved through the development of second-generation feedstocks that do not compete for land or water resources.
"GTL is a good precursor to BTL. We can cash in on local air quality benefits as early as possible and prepare for the emergence of BTL within a wider slate of synthetic fuels," he says.
Rémy points to Airbus's long history in synthetic fuel development, such as partnering with South Africa's Sasol since the early 1990s to develop a certificated semi-synthetic fuel as well as the 26-month EC-funded Cryoplane project that started back in 2000 to assess the feasibility of hydrogen.
Despite Airbus's claims of experience here it admits to wanting to lead the global initiative on alternative aviation fuels, although slightly earlier US-driven initiatives to occupy the same space.
CAAFI - the Commercial Aviation Fuels Alternative Fuels Initiative - a group sponsored by the US Federal Aviation Administration, manufacturers, airlines and airports, and which works with the US Departments of Defense and Energy, NASA, the energy industry and academia - has worked to evaluate alternative fuels for civil aviation since May 2006. This was followed by the establishment of the Airbus Alternative Fuels Advisory Group and IATA Alternative Fuels Project in October of the same year.
"We are not just looking at Europe," says Rémy. "This is a global dilemma that we all face. And certainly we want to partner with the best knowledge resources in the world." Rémy promises an effective strategy and communications policy so that Airbus and its old-world partners can liaise with "external partners" and make the best use of co-ordinating them.
Global initiative
"Certainly as a group we believe that the future fuel - GTL, BTL, whatever it is - will be the same all over the world and we believe that if we succeed in developing and supporting such fuels, it needs to be a global initiative. We certainly welcome international and cross industry collaboration," says Rémy.
"We foresee the establishment of a European-led industry platform in the coming months to discuss alternative fuels, but when we say European-led we don't mean it will be purely European. It will be European-led but with worldwide coverage."
