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Woody biomass is an important feedstock for renewable energy production in the United States. Residues are produced by forest harvests, and some operations utilize this material for energywood. Energywood requires additional processing and is often the lowest value product generated. Additional research quantifying the productivity and costs of energywood operations could allow stakeholders to evaluate the efficiency of those operations and identify areas for improvement. This study evaluated five energywood harvesting operations in the Lower Mid-Atlantic region of the United States (two Appalachian Mountain harvests and three Coastal Plain harvests). Each harvesting operation was observed for 4–7 days, and productivity data were collected on each harvesting function using time study and activity sampling methods. Productivity and costs of each operation were estimated, and equipment mixes and harvesting methods were evaluated to determine efficiency. Interviews were also conducted with each logging contractor to understand operating strategies and decision making. Cut and haul costs averaged (USD) $32.07/tonne and ranged from $26.19 to $38.28/tonne. Hauling consistently comprised the largest function cost at an average of $12.24/tonne. Machines handling energywood were less productive than those harvesting roundwood because of the large effect average stem size had on productivity levels. Harvesting system analysis also highlighted the importance of ensuring a balanced equipment mix to lower costs and ensure efficiency. This research provides stakeholders with a valuable comparison of energywood harvesting operations in the Lower Mid-Atlantic region of the United States that can be used to make better-informed decisions regarding the efficient and economical harvest of energywood. [ABSTRACT FROM AUTHOR]

Biomass is the renewable resource with the potential to serve as a substitute for fossil fuels. A form of biomass, woody residues, includes woody byproducts such as mill residues, logging residues, and other wood waste. This study estimated the impact of woody residue processing capacity, mill willingness to utilize additional logging residues for electricity production, mill equipment upgrades to facilitate electricity production, and different factors limiting the utilization of logging residues on the utilization of woody residues by mills. Data on the utilization of woody residues were collected via a census mail survey of mills in the southern United States. Data were analyzed using a two-stage least square (2SLS) regression model. Results indicated that average utilization was 91% of available woody residue processing capacity for bioenergy. Woody residue utilization increased with an increase in the processing capacity of woody residues, equipment upgrades, and lower transportation costs. In addition, the study found that there were only a few mills with a large enough processing capacity to utilize woody residues for bioenergy production. Thus, an increased utilization of woody residues will be highly dependent on mills' ability to increase woody residues processing capacity, implement necessary equipment upgrades, and lower transportation and processing costs. Logging residue utilization was relatively limited and had less of an impact on overall woody residue utilization. Findings will assist policy makers and mill managers in making informed decisions about woody residue utilization and identify specific mill factors that might help improve the economic feasibility of using woody biomass for bioenergy purposes. [ABSTRACT FROM AUTHOR]

This analysis explores regional aggregate bioenergy potential, the interaction of logging residues and roundwood supply, and the potential supply costs of woody biomass from three southern states. Significant amounts of forest residues are potentially available within the study area: approximately 2.8 million dry tons in North Carolina, 1.8 million dry toffs in South Carolina, and 1.3 million dry tons in Virginia. These quantities are sufficient to satisfy regional biomass electricity production requirements only through 2012 under a hypothetical national Renewable Portfolio Standard and Renewable Fuels Standard, after which changes in the biomass resource stream will be necessary. Supply curves generated for multiple regions in each state indicate that forest residues vary regionally in both supply and price, and exceeding the supply of forest residues could be accompanied by a dramatic spike in resource pricing, with implications for timberland owners and users of the forest resource base. [ABSTRACT FROM AUTHOR]