With the spark of a road flare, engineers at the U.S. Department of Energy's National Renewable Energy Laboratory lit its new, smoke-free Renewable Fuels Heating Plant today. The $3.3 million project is the Laboratory's latest step toward operating as a net-zero energy facility.
The RFHP will heat NREL’s South Table Mountain Campus laboratory buildings by burning woody biomass, including wood chips from trees lost to the region's mountain pine beetle epidemic.
Operating smoke-free and odor-free, the plant will offset about 4.8 million pounds of carbon dioxide each year and as much as 75 percent of the 50,000 million Btus of natural gas used annually to heat the STM campus.
The wood chips are roasted to the point where they are gasified. The wood gases then are mixed with air for complete combustion in the heat recovery boiler. Temperatures in the two-stage process reach 1700° F (930°C), and leave very little ash or soot.
The wood chips for the boiler cost $29 per ton or $2.42 per million BTUs — about one-quarter of the cost of natural gas.
"Wood chips are NREL's best resource for large scale, on-site renewable energy," said RFHP project manager Chris Gaul in a statement.
It doesn't look like there will be a shortage of biomass for the NREL furnace any time soon. As the pine beetles cross the continental divide and move eastward they are expected to wipe out 100% of the state's ubiquitous lodgepole pines.