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There is increasing interest in replacing coal with woody biomass in cofiring plants for electrical power. A variety of pre-treatments can be used to make biomass more suitable for co-firing. This research presents a model that evaluates the delivered costs of various pre-treated biomass sources, electricity production costs, and constraints, and calculates a least cost mix. Results of the scenario presented indicate that wood chips are the most economical co-firing option for delivering biomass to direct-fired boilers. Apart from potential feeding and processing issues, the wood-chips options of forest residues present the lowest cost of electricity production for small-scale co-firing applications. From the options that will ensure minimum processing issues in the co-firing cycle, wood pellets from southern yellow pine represent the most economical choice. Based on coal displacement from the facility, torrefied wood pellets from southern yellow pine is a preferred option as compared to other choices evaluated. An alternative to torrefied wood pellets from southern yellow pine is dark torrefied Eucalyptus benthamii, providing similar electricity production costs while reducing coal utilization.

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Green manufacturing is becoming an important strategy that manufacturing companies are implementing in their facilities to differentiate themselves from competitors. Several research efforts have been done aiming to understand the improvements achieved with green manufacturing. However, additional research needs to be conducted on how companies differ from each other, and how they can compare themselves to leading companies in environmental terms. The objective of this research was to design, verify, and validate a model able to deliver a positioning index (environmental improvement index, EII GM ) that measures the environmental image of a company as a function of their environmental improvements, and as compared to achievements in the same areas by leading companies implementing green manufacturing. The model was developed using a fuzzy logic approach. Main findings indicate that the highest levels in the EII GM are achieved when simultaneously improving the four variables considered (water, waste, energy, and CO 2 emissions), with energy savings being the most important variable for companies improving only one variable. The environmental improvement index developed shows its importance as a planning and decision-making tool for manufacturing companies pursuing a higher environmental image, and a differentiation strategy from competitors based on environmental improvements.

The wood pellet industry has been in a growing trend worldwide. The Southern U.S. has been proposed as a good location to further develop wood pellet industries geared toward the supply of international markets. This research looks into the current status of the wood pellet industry of the region in terms of consumption of biomass, installed capacity, and production levels of wood pellets. It assesses the known future developments for the region (Virginia, North Carolina, South Carolina, Georgia, and Florida). The study also includes an analysis of major ports within the region. Currently, companies within the region have a total production capacity of over 4.7 million tons of pellets, while the current production levels are estimated at 3.1 million tons. Research indicates that at least 20 facilities within the region will be opening their operations, and the expected capacity of the wood pellet industry will then be over 5 million tons of pellets per year. The biomass requirement for the production of these pellets was determined, and the current production level requires over 11 million tons of green biomass (55% moisture content). Future developments may require over 13 million tons, making the industry total over 24 million tons in coming years.