We’ve seen plenty of algae fuel startups pop up in the last year. It’s not surprising–algae has been heralded as something of a miracle biofuel because it doesn’t compete with food crops (unlike corn) and it has high energy yields. But algae might not be worth all the hype, according to a new University of Virginia study published in Environmental Science & Technology. The study claims that algae cultivation actually has higher greenhouse gas emissions and uses more energy and water than traditional biofuels like–wait for it–the dreaded corn. That’s because algae needs nitrogen feed and carbon dioxide to grow–and those greenhouse gases have to come from somewhere.
That doesn’t mean we should give up on algae fuel entirely. Companies like Algenol and Joule Biofuels claim to have developed technology that cultivates algae using minimal amounts of fresh water and nutrients. And the researchers involved in the study believe that putting algae production ponds behind wastewater treatment facilities to capture phosphorous and nitrogen could be one partial solution to the problem. Likewise, some of the required carbon dioxide might come from exhaust captured at coal-fired electrical plants (though this technology is not yet economical).
But ultimately, the University of Virginia study serves as a reminder that it’s never good to focus on a single solution to the sustainable fuel problem. That means alternatives like switchgrass and camelina shouldn’t be counted out–at least, not until someone figures out a workaround to algae’s carbon footprint issue.
Update: In a statement, executive director of the Algal Biomass Organization Mary Rosenthal said, ““We
appreciate and support the interest in algae among the scientific community,
and agree that examination of the life cycle impacts of algae for fuel
processes is important. However, we expect such research to be based on current information, valid
assumptions and proven facts. Unfortunately, this report falls short of those
standards with its use of decades old data and errant assumptions of current production
and refining technologies.”
[Via Greentech Media]