Alaska Airlines says it will fly a demonstration flight next year using 1,000 gallons of a biofuel made from wood waste in Northwest forests. The jet biofuel is being developed by the Washington State University-led Northwest Advanced Renewables Alliance using tree branches left after a timber harvests. The five-year project is being supported by the U.S. Department of Agriculture. Using the wood waste to make jet fuel can reduce greenhouse gas emissions while providing job opportunities in rural timber communities, members of the alliance said. Alaska Airlines is interested in promoting sustainable aviation biofuels, said Joe Sprague, the airlines senior vice president of external communications. In 2011, Alaska Airlines became the first U.S. airline to fly 75 commercial passenger flights using a biofuel made out of used cooking oil. Later this year, Alaska will fly the first commercial flight using an alcohol-to-jet fuel.