Scientists all over the world are looking for ways to use switchgrass as an effective biofuel. They should speak with Tim Reinbott, who has been doing that all winter.
Reinbott, superintendent of the Bradford Research Center, east of Columbia, has substituted switchgrass bales for wood in the furnace that heats the center’s administration building. The fuel is more than cheap – it’s free; harvested on the property.
Reinbott has done more than just chuck the grass into the furnace and enjoy the warmth. He’s evaluated its economic and environmental aspects and found several advantages.
He discovered, for instance, that the BTU output of baled switchgrass is about the same as cordwood, per equal weight. He also measured the energy output of a ton of switchgrass and found it was equivalent to about 200 gallons (1,660 pounds) of propane.
Baled switchgrass burns at about the same temperature and burn duration as wood, so there is no diminishment of comfort or convenience. Matt Volkmann, agricultural science research technician for the USDA’s Agricultural Research Station in Columbia and who originally suggested experimenting with baled switchgrass, found that on a typical cold winter day a 250 pound half-bale in the morning and another in the afternoon keeps a large building sufficiently toasty – about the same as with cordwood.
Unlike cordwood, Volkmann and Reinbott also found that there was significantly less ash residue with switchgrass than wood. Reinbott last year experimented with discarded wooden pallets in the furnace and found, that while they burned well and were cheap, they produced fairly large amounts of ash and nails that had to be cleaned out and discarded.
“Ash produced from burning switchgrass is not only less in volume, but it is powdery, making it easier to dispose of,” Reinbott said. “Switchgrass ash also is high in minerals, so we spread it back into the soil as a free fertilizer.”
Reviewed 2015-01-26