An Alaska case study: Biomass technology

Abstract

This review examines commercial biomass boilers installed around the state of Alaska for key performance and cost metrics. Capital costs and operation and maintenance costs vary with the boiler type and location around the state. Most boiler manufacturers claim system life expectancies of 20–30 years, assuming normal running conditions and adherence to maintenance schedules. System efficiencies vary with the biomass system type, installation protocol, operation and maintenance protocols, piping distance, thermal storage, and wood moisture content. Sizing biomass units to meet approximately 80% of peak required heat load ensures that the boiler will run at the maximum heat output. The boiler itself presents the highest cost for most installations. Other substantial costs include the site foundation, the boiler building, and the integration of the system into the building. Fuel storage and construction management are also large expenses although not reported in each project. Despite the large installed capacity of chip boilers in the Interior, their installation costs per installed BTUh are higher than those of other boilers.