[Editor’s note: This post, by Scott Thill, originally appeared on SolarEnergy.net.]
Consolidating precious natural resources in a warming world is a must. Which is why literal solar farms make sense — and maybe dollars — to Stanford scientists recently researching a colocation approach for simultaneously creating solar power and biofuels. It’s a simple idea, really: Grow some agave plants beneath vast solar farms across Earth’s increasingly arid regions, and voila! You’ve got a potential agritech solution for decreasing lethal emissions, and perhaps a reliable source of domestic fuel.
More microcosmically, the solar sector could reduce its water footprint by relying instead more heavily on agave, and what Stanford’s colocation announcement called “other biofuel crops,” to capture runoff and moisture to keep our photovoltaic panels cleaner in inhospitable climates. It sounds good on paper; specifically, the new issue of Environmental Science & Technology wherein Stanford’s scientists explain their collocated energy concept.
“It could be a win-win situation,” said Stanford postdoc Sujith Ravi in a press release. “Water is already limited in many areas and could be a major constraint in the future. This approach could allow us to produce energy and agriculture with the same water.”
Ravi and Stanford earth science professors David Lobell and Chris Field sound like they have their hearts and minds in the right place. But the science and math are eventually where this battle for the next generation of energy will be fought and won, and the numbers on biofuels are crunching more complicated these days. A recent study published in the journal Nature Climate Change argued that transforming corn into ethanol (“and other biofuels”) degrades soil carbon and releases more greenhouse gas than gas itself. “It’s final,” Forbes wrote, “corn ethanol is of no use.”
“Unlike corn or other grains, most of the agave plant can be converted to ethanol,” Ravi explained in the Stanford announcement. “Of course, creative solutions don’t always work in the real world, but this one at least seems worthy of much more exploration,” added Lobell, perhaps not forcefully enough.
Because although the colocation approach is a brilliant idea, water is growing quite scarce and biofuels emissions, whether from corn or agave, are what we need to be moving away from, not toward. Maybe we should just skip that stage and just grow agave to keep the solar farms company.
Solar farm photo courtesy of Stanford News Service.