Research Project Summary Information
Identifying the Barriers to Biogas Generation and Use at WWTPs(20311)
Water Environment Research Foundation
Wastewater treatment facilities (WWTFs) are built to reduce impacts on nature, but they can be energy-intensive to operate and they produce greenhouse gas emissions and residuals that are costly to manage. The US Environmental Protection Agency (US EPA) reports that fewer than 20% of the larger WWTFs with anaerobic digestion operations beneficially use their biogas beyond process heating. The most common form of biogas use is to produce combined heat and power (or CHP, largely used interchangeably to represent the myriad forms of biogas beneficial use). Thus, there must be actual or perceived barriers to broader use of these heat-capture or energy recovery technologies. Anecdotally, known barriers include the following:
• Lack of financial incentives
• Capital investment perceived as too high
• Technology seen as not appropriate for the size/scale/processes of the facility
• Cannot sell energy back to grid
• Lack of expertise on staff or on call
• Too expensive to buy, or own/operate, the equipment
• Cannot get CHP air permit, or CHP will require a Title V permit
• Payback is not great enough
In 2011, the Water Environment Research Foundation (WERF) and NYSERDA conducted a study with Brown and Caldwell, Black & Veatch, Hemenway Inc., and the Northeast Biosolids and Residuals Association (NEBRA) to determine what barriers wastewater utilities face in implementing
anaerobic digestion and combined heat and power projects.
The project team developed an online survey to determine the most significant barriers facing utilities; this survey was distributed nationally and completed by more than 200 respondents. The survey findings were presented and discussed with dozens of utility representatives at four focus groups – in Miami FL, New York NY, Sacramento CA, and Chicago IL – timed with industry conferences.
To develop the survey and discussion areas for the meetings, the project team used available baseline information about biogas uses for renewable energy and about known uses within the industry. These uses are divided into two categories:
• Uses in CHP processes, including internal combustion engines, combustion gas turbines, microturbines, fuel cells, and steam turbines.
• Non-CHP uses, including injection of biogas into natural gas pipelines, sale to third-party end users, and use as vehicle fuel.
To build on the work completed in this project, the following next steps are recommended to increase biogas-generated renewable power at WWTPs:
• Continue to quantify and define the energy generation potential from biogas at WWTPs throughout the United States.
• Develop databases, similar to that developed by US EPA Region 9, of potential HSW sources that could be used to increase biogas production at WWTPs.
• Develop a consolidated database or repository of grant funding opportunities for CHP projects.
• Update the University of Alberta Flare Emissions Calculator to include nitrogen oxides (NOx) and carbon monoxide (CO) that are often regulated by permitting agencies to document the relative performance of these non-recovery/fuel-wasting devices against CHP technologies.
• Expand outreach and information exchange between the wastewater industry and power companies and natural gas utilities.
• Further explore how utility decision-making and innovation diffusion theory can help overcome barriers to biogas use for renewable energy at wastewater treatment utilities.
Many of the findings of the project were not surprising. Of the ten barrier categories introduced as potential barriers at the beginning of the project, nine were deemed significant, according to the broad input and testing conducted. However, it became clear that the economic barriers – inadequate payback/economics and lack of available capital – were dominant. Other barriers fell into two categories: policy factors such as regulatory permitting, and human factors, such as decison making.
Water Environment Research Foundation
635 Slaters Lane
Alexandria, VA 22314
Waste Management and Pollution Prevention
Water/Wastewater treatment systems
NYSERDA Contact Information
R&D - Environment & Energy Res