The objective of this project is to demonstrate, characterize, and model anaerobic co-digestion of food waste, fats, oils and grease (FOG) and wastewater sludge at the Target Hill Wastewater Treatment Plant (WWTP) at West Point, NY in order to construct a decision support tool for leadership at other Department of Defense (DoD) installations. The tool will help installation leadership determine how co-digestion can help them meet their energy security and energy resilience goals, reduce reliance on external electrical grids, save money, and reduce environmental impacts. As of late 2022 or early 2023, West Point will have the only continuously-fed full-scale anaerobic co-digester on a DoD installation. The project team has a tremendously unique opportunity to study this emerging technology and determine how its capabilities can be best transitioned to installations across DoD. This technology can turn critical, yet vulnerable, water and wastewater infrastructure into self-sufficient (i.e., energy-independent), energy-resilient infrastructure.

Anaerobic co-digestion leverages the metabolism of anaerobic (without oxygen) microorganisms in a sealed bioreactor to convert organic wastes to methane-rich biogas. This biogas can then be treated and combusted using existing technologies like a microturbine for on-site energy generation. Anaerobic co-digestion of food, FOG, and wastewater sludge at wastewater treatment facilities is an emerging technology that has been demonstrated at several locations treating large wastewater flows (i.e., > ~15 million gallons per day); however, the technology is not well-demonstrated at wastewater treatment facilities treating lower flowrates like those observed on DoD installations (< 5 million gallons per day). Beyond directly characterizing the anaerobic co-digester at Target Hill, this project also will leverage wastewater treatment modeling, lifecycle costing, lifecycle environmental impact, and uncertainty software to take real-world data and create predictive models. Data from predictive models will inform the creation of a decision support tool that will help installation leadership determine how co-digestion will best work at their installation, and if the construction of a microgrid that integrates electrical energy generated from the co-digestion process is feasible. Last, the decision support tool will include cutting edge resilience assessment approaches to help installation commanders understand the resilience payoff for anaerobic co-digestion within energy security and energy resilience analyses. The project also intends to study relevant aspects of co-digestion that impact technology transfer, to include installation-level barriers to full implementation, interaction of installation and privatized wastewater companies (e.g., American Water), and adherence to state-level regulations.

Anticipated DoD benefits include: (1) Enhanced understanding of the resilience of WWTPs due to the addition of anaerobic co-digestion, to include the ability to maintain or rapidly recover functionality during an extended grid outage. (2) Increased knowledge concerning the efficacy of anaerobic co-digestion as a means of energy independence from external electrical energy grids for WWTFs, as well as understanding if this renewable energy approach can contribute energy to a local microgrid. (3) More complete understanding of lifecycle costs, environmental impacts, barriers to implementation, and partnerships with privatized partners with respect to water and wastewater on DoD installations. (4) A transferable decision support tool that will assist installation commanders to determine the efficacy and resilience payoff of using organic wastes for thermal and electrical energy generation.