AMSTERDAM (AP) -- Within a decade, passenger planes will be flying on jet fuel largely made from plants -- flax, marsh grass, even food waste -- as airlines seek to break away from the volatile oil market and do their part to fight climate change, aviation experts said Wednesday.
Though biofuels are still in the experimental stage, the projected shift has stoked concern among environmentalists that the possible insatiable appetite of airlines for plant oil will hasten the destruction of tropical forests and the conversion of cropland from food to fuel.
Dependency on agrofuels "will lead to faster deforestation and climate change and spells disaster for indigenous peoples, other forest-dependent communities and small farmers," said a statement from the Global Forest Coalition, an alliance of environmental groups.
But aviation experts told a global biofuels conference the industry is focusing on fuels that cause minimal environmental destruction.
A Swiss-based organization, the Roundtable on Sustainable Biofuels, has drawn up standards for certifying the entire chain of production. "Not all biofuels are created equal," said Victoria Junquera.
Controlling greenhouse gas emissions from aviation and shipping is an unresolved issue in negotiations on a global climate change agreement leading up to the next major climate conference in Mexico next November.
The European Union has decided that by 2012 all flights into and from European airports will be subject to the European carbon trading program. That means airlines will be given a limit on how much carbon dioxide they can emit, and they can buy or sell carbon credits depending on whether they are over or under their targets.
Airlines emit roughly 2 percent of human-caused greenhouse gases, but until the economic recession the aviation industry was among the fastest growing polluters. The carbon emitted by aircraft tens of thousands of feet (meters) high also remain entirely in the atmosphere, while carbon from ground level is partly absorbed by soil or oceans.
Five test flights have been conducted since 2008 by different airlines using up to 50 percent biofuels in one engine, including once on a twin-engine Boeing 737-800 using a mix of jatropha and algae.
More recent flights have used camelina, a mustard-type flax used as a rotation crop in northern Europe and North America for farmers to rejuvenate tired soil.
British Airways is participating in a pilot plant that produces jet fuel from waste that normally would be dumped in a landfill.
A pilot project also is under way in the Persian Gulf state of Abu Dhabi with halophytes, salt-water plants like mangroves and marsh grass that can be grown in conjunction with fish or prawn farms, said Terrance Scott, an environmental spokesman for Boeing.
Biofuels are likely to be approved for commercial use by the end of this year by ASTM International, the organization that develops standards routinely adopted by U.S. federal agencies, Scott said.
"We have developed advanced biofuels that are safe and can be grown in a sustainable manner," said Mark Rumizen of the Federal Aviation Administration.
Thomas Roetger, of the International Air Transport Association, said biofuels are expected to reach the break-even point and largely replace kerosine fuels within the next decade. "Everything looks very promising," he said.
Roetger said IATA's goal is the increase fuel efficiency by 1.5 percent every year until 2020 when the growth of carbon emissions level off, and to reduce emissions by half by 2050.