Divya Ramchandran, who wrote the study as his master’s thesis, noted the water efficiency issue: the production of ethanol from corn requires three to four gallons of water for each gallon of ethanol produced; that ratio spikes up to six to 10 gallons of water for each gallon of cellulosic ethanol. In world more stricken by drought, such ratios are a huge hurdle for cellulosic ethanol—and investors—to overcome.Should Ramchandran’s work show promise, the future of cellulosic ethanol production could shine brighter, especially since plants used as feedstock for this fuel often grow in water stressed areas from India to the San Joaquin Valley. Some ethanol plants have promised to treat their wastewater and use it for irrigation water, but the possibility of using municipal or agricultural effluent could help this holy grail of clean energy scale without the troublesome impact on local water supplies.
Though this news is promising, it’s far too early to be calling cellulosic ethanol a “holy grail” energy source. Unfortunately, that is in effect what the government has been doing through it policy. Quotas from the EPA mandated 20 million gallons of the biofuel’s production since 2010, yet actual production has been near-zero, and the quotas were eventually struck down by a federal appeals court, which called those targets “wishful thinking.” Embarrassments like these serve as a reminder that propping up new technologies with mandates and subsidies before they’re ready for the market isn’t smart policy.Rather than setting ambitious policy goals based on wishful thinking, we would like to see more research along the lines of this University of Illinois study to make sure the technology is viable. There’s potential here, but we need to see more results before we start hailing it as a game-changer.[Wastewater treatment plant image courtesy of Shutterstock.]