The following post is related to the Center’s work on a Health Impact Assessment of a proposed biomass-powered energy facility in the Shenandoah Valley of Virginia. The facility was proposed as a potential remedy to the issue of nutrient concentration related to trends in livestock production. Each post in the series describes one particular aspect of interest from the Center’s analysis.
Litter Supply
In April of 2012, a report out of Virginia Tech estimated the total amount of poultry litter produced annually by Valley poultry growers to be around 345,000 tons, significantly less than previously presumed. Following this finding, the Virginia Department of Environmental Quality (DEQ) halted its investigation of the feasibility of the facility in addressing its nutrient reduction requirements (see the previous post on the HIA background) and Fibrowatt LLC tabled the development of a proposal for a facility in the Valley.
At this time, there is no indication of whether the proposal development will ever be resumed but if it is, a facility in the Valley would probably be different from any other existing large-scale, poultry litter-to-energy facility. The facility in Benson Minnesota burns 700,000 tons of fuel annually—about three quarters of that is poultry litter with the rest made up of woody biomass. Without importing litter from other areas, growers in the Valley could not support such a facility which would mean a facility in the Valley would either be significantly smaller or burn a much higher ratio of woody biomass to poultry litter.
Poultry Litter Vs. Woody Biomass
There is some benefit to a facility that burns a high percentage of woody biomass; mainly that it provides some room for growth of the poultry industry in the Valley. As the population grows, demand for poultry is likely to increase. If using litter as a fuel source addresses excess nutrients that are seen today but leaves no room for further expansion, poultry growers in the Valley may be facing future restraints on growth due to issues with managing litter. If the facility retains the capacity of increasing the amount of litter it burns through reducing the amount of woody biomass it burns, poultry growers can increase poultry production without the concern that additional litter will again create issues of nutrient concentration.
However, combustion of woody biomass may also increase health risk. Burning woody biomass does not address the core concern for which the facility is proposed—reducing the concentration of unnecessary nutrients—but it still impacts air quality. In addition, the impact on air quality from the combustion of woody biomass cannot be expected to be the same as the impact from combustion of poultry litter. Preliminary analysis from the North Carolina Environmental Management Commission suggests that wood combustion in comparison to poultry litter contributes higher emissions rates of several pollutants including fine particulate matter.
When evaluating the benefits and detriments of the facility to the Valley, a key consideration should be the type of fuel that is proposed to be used in the plant operations. What works for the facilities in Minnesota or Europe, cannot be presumed to be sufficient to work in the Valley. In order to be truly beneficial to the community, the facility—if built—should be tailored to the Valley’s specific needs.