The greatest irony of America’s 21st Century quest for energy independence is that it – whatever “it” turns out to be – most assuredly has been here all along! And none of the emerging cellulosic bioenergy feedstocks fits that description better than switchgrass, which once covered the continent from sea to shining sea! Photo courtesy Ceres, Inc.
Switchgrass WAS the great American prairie; the stuff that covered today’s Corn Belt before the “sod busters” came along and plowed it under in the 1800s; the grazing fodder for those herds of bison who roamed in its waves for thousands of years until we nearly killed them off; and finally the food stock for America’s livestock until modern scientific agriculture provided more efficient solutions.
Finally reduced and relegated to such embarrassing but necessary roles as roadside erosion control, field dividers and ornamental grass in parks and gardens, switchgrass stands today on the threshold of a return to its glorious past – once more on the “top of the heap,” so to speak!
Hundreds of millions of dollars – much of it by major agricultural, chemical and petroleum companies – have been plowed into the development of pilot cellulosic biorefineries in the past few years, all of them seeking to prove efficient conversion technologies for our next generation biofuel. The jury is out on this precise outcome for several years, but a general conclusion is clear: Cellulose is for real!
And switchgrass is emerging as one of the major cellulosic feedstock candidates for several reasons. Proponents usually cite the fact that it can be grown almost anywhere and in virtually any condition from drought to heavy water environments. They also tout its high density and relatively low input requirements, including ease of harvest. And lately, they can ballyhoo that its energy output ratios per acre are far greater than those of corn ethanol – as high as 5.4 times according to recent studies.
The latest environmental selling point for switchgrass is its extremely high carbon retention. Because of its deep fibrous root system and the fact that it is a perennial and doesn’t decay in the field, switchgrass has virtually zero greenhouse emissions. U.S. Department of Agriculture studies have proven this is a 94% offset against the total emissions from planting, harvesting and combustion of the ethanol derived from it – putting switchgrass into a class of its own in comparison to other biomasses.
These arguments for switchgrass are about to heat up. Starting with the current growing season, seeds from the first bio-engineered high-yield varieties of switchgrass are being planted across the country and eventually will become feedstock for a number of biorefineries. Tailored to suit different climates and ethanol production methods, the seeds are produced by Ceres, Inc., an agricultural genomics research firm in Thousand Oaks, CA, that is marketing them under the brand Blade Energy Crops.
Current varieties of switchgrass have been hybridized through the years, but the Ceres effort probably is the first to target switchgrass for cellulosic bioenergy. Using advanced plant breeding techniques, Blade – and whatever competitors evolve – will produce intensely higher yields of energy per acre as their biotechnology evolves. So, already, even before it’s yet an energy staple, switchgrass has started down the same proven yield-improvement path as corn and other commodities!
In operation since 1997, Ceres already has made major contributions to this field, and since 2002 has been in a $137-million collaboration with Monsanto, as well as other partnerships applying the techniques used in the Human Genome Project to crops, mostly in the development of dedicated energy crops. In addition to switchgrass, Ceres also just introduced bio-engineered seed for high-biomass sorghum.
Richard Hamilton, Ceres president and CEO, likes to point out that it took “66 years to go from Kitty Hawk to the moon.” His implication, of course, is that we ought to be patient.
But when you think about it, this could be a much shorter trip – thanks to switchgrass and other cellulosic biomasses, and the national desire for energy independence.