Algae can be grown as a feedstock for biofuels. Biodiesel is the most common product, but the sugars in algae can also be extracted to produce ethanol, while the solids can even be harvested to produce a high-protein animal feed. Self-contained operations can grow lots of algae in a small space (in tubes or vats) or in outdoor algae ponds—which take up more land area. A New Zealand company, Aquaflow, even plans to harvest wild algae from coastal areas with algal blooms.

Researchers test different types of algae to see which produces the best oil to use for biodiesel formation.

Algae for biofuels growing in above-ground ponds.

AP Photo/Coloradoan, Sherri Barber
Antonio Luis Campos/4SEE/Redux