Environmental Impact Assessment of an Anaerobic Codigestion System in Western New York State

Abstract

Anaerobic codigestion of dairy manure and food-based feedstocks reflects a cradle-to-cradle approach to organic waste management. Given both of their abundance throughout New York State, waste-to-energy processes represent promising waste management strategies. The existing waste-to-energy literature has not yet fully realized the environmental impacts associated with displaced grid electricity generation and feedstock-hauling emissions on the net environmental impact of centralized codigestion facilities. The key objective of this study is to provide a comprehensive environmental impact assessment with the purpose of understanding the existing environmental status of centralized codigestion facilities. Real-time data from an operational codigestion facility located in Western New York State was used to conduct this environmental impact statement. A comprehensive inventory of greenhouse gas emissions associated with renewable electricity production at the codigestion facility was developed using the Emissions & Generation Resource Integrated Database (eGRID) (U.S. EPA), while emissions associated with feedstock hauling were quantified using the fuel life-cycle approach developed by the Greenhouse gases, Regulated Emissions, and Energy use in Transportation model (GREET) (U.S. DOE). With each of the emissions models used for this analysis, it was determined that the net environmental impact associated with hauling food-related feedstocks from the many locations throughout the Northeast U.S. region would be acceptably low, and thus could be part of future sustainable development of centralized codigestion facilities.