San Francisco Chronicle: Air New Zealand conducted a two-hour test flight Monday in which one of four Rolls-Royce engines on a jetliner was powered by a biofuel blend, another step down the long path the airline industry is taking to reduce carbon emissions. Engine No. 1 of the Boeing 747-400 that departed Auckland International Airport was fueled by a 50-50 blend of standard Jet A1 fuel — effectively kerosene — and synthetic paraffinic kerosene derived from Jatropha oil, which comes from a shrub that grows …