Algae biodiesel has looked so promising (as in 100 times more fuel than corn or soy) that the U.S. Department of Energy gave $9 million to Cellana, a joint research venture between Shell Oil and HR Biopetroleum, specifically to look into the alternative energy source's prospects. It seems, however, that those prospects were no longer attractive to Shell, which has announced it will no longer pursue algae biodiesel, because it feels it doesn't have sufficient commercial viability. Partner HR Biopetroleum has stated it cannot continue the project on its own as Shell pursues other biofuel initiatives with other companies.