An Analysis of the Potential Environmental Remediation and Economic Benefits Anaerobic Digesters Offer to the Dairy and Swine Industries: A Comparison of China and the U.S.

Abstract

The purpose of this research is to investigate the environmental remediation and energy potential of anaerobic digesters on pig and dairy farms and to demonstrate how incorporating those benefits into a cost-benefit analysis would make biodigester projects more financially feasible. By assigning dollar values to the emissions and water pollution avoided by this technology, I sought to update the traditional cost-benefit analyses (CBAs) to demonstrate that this technology is more widely applicable. The study took place In the Lake Champlain Drainage Basin, USA and the Lake Tai Drainage Basin, China. Dairy and pork production are high density endeavors and produce large quantities of waste which make them ideal candidates for biodigesters. Using standard emissions estimates and gas production rates from past research and from the current Cow Power Program in Vermont, the methane and nitrous oxide emissions averted by adding a biodigester to a particular farm were estimated. Additionally, using past research, the total nitrogen and phosphorous collected by the biodigesters and diverted from becoming classified as non-point source pollution was calculated, valued, and incorporated into a CBA tool. The results from this study show that the incorporation of environmental benefits in a CBA for Green Mountain Dairy increased profitability by 60% and reduced the payback period by two years. Overall, projects that include environmental benefits are 72% more profitable and the payback period is cut in half. Further development of the CBA tool is needed to strengthen results. This study points to the need for more experimental data on the environmental benefits of biodigesters.