Running on renewables

One of the biggest challenges with renewable energy technologies is scaling up beyond the experimental phase. The U.S. Navy, in its mission to cut its use of fossil fuels for security reasons, is a customer of algae fuels from Solazyme and others. This RCB-X is powered by an alternative-fuel blend of 50 percent algae-based and 50 percent NATO F-76 fuels. Research on algae fuels in the U.S. began back in the 1980s and, like solar and wind, lost funding as oil prices went down. Algae saw a resurgence in the 2000s, but it's still difficult to make algae biofuels at competitive prices with oil.