To bring the price down, many more processing plants needed to be built and yields increased, he said.
"The industry has identified the feedstocks [for biofuels]. However, moving from concept to commercial scale still carries challenges," Woodward said. "A lot of the work is about getting processing efficiencies like cost and CO2 related emissions."
The International Air Transport Association has pledged to cut aviation emissions by 1.5% a year to 2020, although the European Union is trying to persuade the industry to agree to cut emissions by 10% from 2005 levels by the same date.
Both are tough targets given the steep rise in the number of flights globally.
Woodward said some test flights had used vegetable oils but these were not cheap at $1,200/mt compared with $750/mt for traditional jet fuel.
He said 60 commercial scale plants dedicated to biofuel production needed to be built in order to both meet the carbon targets and achieve economies of scale.
Airlines might be willing to help with some of the initial costs of this switch to biofuels, but government aid would also be necessary through ring-fenced tax revenues, said Sabrina Bringtown, Environmental Affairs Manager at Air France.
"Revenues generated by governments [through taxes] from carbon emissions should be directed to finance the biofuels sector," she told the meeting, adding that her airline and KLM might be willing to bear some of the initial costs.
