Homegrown algae blooms could supply up to one-twelfth (8.3%) of the fuel demand in the U.S., new research shows.
However, substantial barriers to efficient algal fuel production mean that creative solutions are needed to make the technology commercially viable.
Oil is a major component of algae, and existing studies have focused on growing these microscopic plants with higher oil levels, creating algae that live longer and thrive in cooler temperatures, or devising new ways to separate the oil from the rest of the bloom.
The newest study was aimed at figuring out how much water would be needed to grow a large amount of algae, which thrive in shallow ponds located in hot, humid, and wet environments such as the Gulf Coast and Southeastern seaboard.
The U.S. is capable of producing up to 25 billion gallons of algal oil per year, enough to cover roughly one month of current annual oil demand, according to the study results, which were published in the American Chemical Society journal Environmental Science and Technology.
However, producing this much algae would require the equivalent of about 25% of the water used for U.S. agriculture every year. The technology can use saltwater instead to preserve freshwater supplies, but this requires significantly more equipment and infrastructure to either pump saline water out of deep reserves or move seawater from the coast to processing plants.
This means that the cost of making algal biofuel is greater than the cost of gasoline-based products. But water access doesn’t present an insurmountable challenge, says Erik Venteris of the DOE’s Pacific Northwest National Laboratory, a co-author of the study.
“There are many details still to be worked out, but we don’t see water issues as a deal-breaker for the development of an algae biofuels industry in many areas of the country,” Venteris adds.