Library Item
An Economic Analysis of Bio-Energy Options Using Thinnings from Overstocked Forests
Description:
The economic feasibility of producing bio-fuels and ultimately
bio-energy by utilizing thinnings from overstocked forests is examined.
Large areas of forest in the western US are severely overstocked with
small diameter trees, and as such, pose extreme risk for catastrophic
wildfires. Physical removal of such small diameter trees, or forest
“thinning,” is the best solution to the wildfire problem, and
represents a potential raw material for the production of bio-fuels.
Production of (1) wood pellets, (2) bio-oil, and (3) methanol all
represent potential conversion pathways which would utilize
unmerchantable forest thinnings as the feedstock. Wood can also be
directly combusted, either in conjunction with another fuel such as coal
or on its own to generate steam and electricity. This study examines the
potential for accomplishing both forest wildfire reduction and the
generation of energy using a single integrated pathway. The economic
effects of thinning scale, thinning duration, and distance to end-use
markets are quantified. Co-firing of thinnings with coal is currently
found to be the most viable option for transportation distances of less
than 500 km. Beyond 300 km transportation distance, pelletization, fast
pyrolysis, and methanol synthesis become increasingly cost competitive
for different ranges of thinning yield and duration. Bio-energy options
are economically preferable to landfill or open burning disposal of
thinned biomass; however, revenue from bio-fuels will not cover the cost
of thinning. Results for a range of thinning scenarios are visualized
using technology maps.
