Scientific American: Air New Zealand became the second airline to fly partially on biofuel–and the first to use jet biofuel refined from a non-food crop. Fuel from the weed jatropha powered an Air New Zealand jet on a two-hour flight today–the world’s second flight of a commercial jet on biofuel. One out of the four Rolls Royce engines on an Air New Zealand Boeing 747-400 burned a 50-50 blend of regular jet fuel and a bio-version made from jatropha. The flight more than doubled the air time of …