Feasibility of using wood wastes to meet local heating requirements of communities in the Kenai Peninsula in Alaska.

Abstract

Wood energy can be important in meeting the energy needs of Alaska communities that have access to abundant biomass resources. In the Kenai Peninsula, a continuing spruce bark beetle (Dendroctonus rufipennis (Kirby)) infestation has created large volumes of standing dead spruce trees (Picea spp.). For this evaluation, a site in the Kenai-Soldotna area was chosen for a small, industrial-scale (4 million British thermal units (BTUs) per hour) wood-fired hot water heating system, which could be fueled by salvaged spruce timber and also by sawmilling residues. Thirty-six different scenarios were evaluated by using wood fuel costs ranging from $10 to $50 per delivered ton, alternative fuel costs from $1 to $2 per gallon, and fuel moisture contents of either 20 percent or 50 percent (green basis). In addition, two different capital costs were considered. Internal rates of return varied from less than 0 to about 31 percent, and project payback periods varied from 4 years to greater than 20 years. Potential barriers to the long-term sustainability of a wood energy system in the Kenai Peninsula include the availability of biomass material once current spruce salvage activities subside. The estimated wood fuel requirements of about 2,000 tons per year are expected to be easily met by spruce salvage operations over the short term and by sawmill residues after salvage inventories diminish. It is expected that a wood energy system this size would not significantly reduce overall fuel loads in the area, but instead would be a good demonstration of this type of system while providing other community benefits and energy savings. Abstract 1 Biomass energy can be important in meeting the heating needs of facilities that currently depend on fossil fuels. The Kenai Peninsula region of Alaska has abundant forest resources , which include a substantial amount of spruce (Picea spp.) wood killed by bark beetles (Dendroctonus rufipennis (Kirby)). This region of Alaska holds promise for the development of biomass energy projects not only because of its timber resources but also the presence of an existing timber industry (both processing and logging infrastructure). Salvaged material could be used to produce energy to heat buildings, although its long-term supply might be questionable. Many sawmill facilities in the region would be well positioned to supply wood wastes for fuel if the availability of beetle-killed wood declines. This paper evaluates the economic feasibility of using local forest and sawmill residues to supply a wood-fired hot …