A New Zealand Air passenger jet partly that is powered by vegetable oil recently completed a 2-hour flight in an effort to test a biofuel that could lower airplane emissions without competing for food crops. One of 4 engines on the Boeing 747 airplane was powered by a 50-50 blend of standard jet fuel and oil from the seeds of the jatropha tree. Jatropha trees grow on marginal land in countries such as India, Tanzania, Mozambique, and Malawi. Each seed produces up to 40% of its in oil, and jatropha can be grown in otherwise agriculturally tough areas, which leaves quality land available for food crops..

2008 has witnessed an unprecedented push for alternative fuels by airlines, which were hit by increasing oil prices earlier in the year and are now bracing for a recession in air travel during the current global economic slowdown. For its part, Continental recently declared plans to test second-generation biofuels by flying a plane over the Gulf of Mexico next week with fuel derived from algae and jatropha. In February, Boeing and Virgin Atlantic had test flight that included a biofuel mixture of palm and coconut oils, but it was dismissed as a publicity stunt by environmentalists who said the fuel could not be produced in the amounts needed for commercial flights.

Air New Zealand expects the blend to be “cost competitive,” based on a company spokeswoman Tracy Mills. Biofuels were once considered to be not useful for airplanes since they usually freeze at the low temperatures of cruising altitudes. However, more recent tests show jatropha oil has an even lower freezing point than jet fuel.