It is widely known that corn ethanol is driving the growth of the Gulf of Mexico's "dead zone." Now, surprising new data suggests that switching to non-food cellulosic fuels won't help the problem one bit.
The "dead zone" is an oxygen-starved black hole that swells each spring and summer as toxic nitrogen fertilizer runs off the cornfields of the U.S. Midwest, down the Mississippi River and into the Gulf of Mexico.
The nasty nitrates breed algal blooms on the water's surface, absorbing oxygen and depriving sea dwellers of their prime life source.
The zone has been around for 50-odd years. In 2006, it measured over 6,600 square miles. Last year it grew to 10,500 square miles — the size of Massachusetts. The culprit? The corn biofuel boom that's been spurred along by aggressive U.S. government ethanol mandates.
The result could be a potential ruin of a $3 billion fishing industry and an entire aquatic ecosystem.
And that is why the U.S. Environmental Protection Agency (EPA) has pledged to bring a substantial chunk of the "dead zone" back to life by 2015. But if they're looking to next-gen biofuels to be a magic cure-all, they may want to think again.
A new analysis by Carnegie Mellon University finds that growing non-food, cellulose-based fuels like switchgrass instead of corn would cut nitrate run-off up to 20 percent. That sounds significant. But it wouldn't be enough to shrink the "dead zone" one iota.
The reason is the bloated biofuel goal in the Energy Independence and Security Act (EISA) of 2007. EISA calls for the production of 36 billion gallons of biofuels by 2022 — about 15 billion of it corn ethanol, the rest "advanced biofuels."
Reaching that target will cause the dead zone to expand dramatically, "regardless of the selection of crops," says the report.
"The presented results demonstrate that using cellulosic crops for biofuel production will decrease TN [total nitrogen] loading to the NGOM [Northern Gulf of Mexico] relative to corn but overall TN loading will still increase as the goals of the EISA are met ..."
Short of dumping the mandate — a political impossibility — there is only one option, according to the researchers: aggressive nitrogen mitigation strategies.
The research is a small blow to cellulosic ethanol, long considered the holy grail of biofuels. The sector has been heralded as the environmentally responsible replacement for grain-based fuels, particularly corn. No wonder.
Corn biofuel has taken a beating in recent years for being a biofraud. The industry has proven that it raises the cost of corn-based food crops worldwide; uses as much as 2,000 gallons of water for every gallon of ethanol produced; and contributes little or nothing to the reduction of greenhouse gases.
Not so with cellulosic fuels. It is believed they would achieve CO2 emissions cuts of 80 percent below gasoline, and even carbon neutrality in some cases. They thrive in places that are often ill-suited for growing food and require little or no irrigation.
But next-gen biofuels may not be the "green bullet" that some assume. And technology-wise, they are still not ready for prime time. Currently, there are just a handful of pilot plants in the U.S. that are churning out roughly 1 million gallons a year.
This is not a bad thing. The lack of adoption of next-gen biofuels means the U.S. has a chance to not follow the fate of corn ethanol — to instead adopt careful policies from the get-go that are based on rigorous science. A group of 32 scientists made this vital point last year in an article published in Science.
Their hard-hitting words are even more relevant today, as these non-edible fuels gain political traction:
"We know that the development of cellulosic feedstocks has substantial promise for avoiding many of the environmental challenges that face grain-based biofuels. ... But however promising, these environmental benefits are by no means given. Whether they are realized will depend on which, where, and how cellulosic biofuels are produced And tradeoffs are unavoidable ..."
"Legislated environmental performance standards for cellulosic ethanol production could, for example, go far toward promoting sustainable outcomes. ... We know enough today to begin formulating these standards, and both the industry and the environment will benefit from their early identification and refinement."
Sustainable biofuel production systems could play a highly positive role in mitigating climate change, enhancing environmental quality, and strengthening the global economy, but it will take sound, science-based policy and additional research effort to make this so."