About the Model

Dairy and swine farms

Over the past decade, there has been increasing interest in the United States to assess the impacts associated with animal husbandry operations, specifically related to the emission of greenhouse gases, ammonia, and criteria air pollutants. At the same time, operators have explored the benefits associated with various mitigation projects, such as anaerobic digesters with biogas collection, to control emissions and benefit from the generation and recovery of renewable energy (biogas).

The MAnure and NUtrient Reduction Estimator tool, or MANURE tool for short, provides a system to quantify methane and other greenhouse gas emission reductions and the environmental benefits of renewable energy produced by digesters at dairy and swine operations. The tool is based upon a full and accurate assessment of baseline conditions at the animal feed operation, which is a key element of the emission reduction calculation. This tool can be used to assess the quantity of emission reductions associated with implementation of specific technologies and/or practices. The tool is meant to be used for actual projects using site-specific measured data. In some cases, the model is set up to use default values if site-specific data are not available. However, the user should input site-specific data as often as possible to increase the validity of the model results. The tool will provide an estimate of methane, direct and indirect nitrous oxide, and ammonia reductions associated with the user's scenario. The tool will also provide a summary report of the data input for each emission reduction scenario.

This tool development effort is part of a larger effort to spur the commercialization of biopower and bioproducts from animal feed operations throughout the country by capturing the economic value of their multiple environmental benefits. This will be accomplished by creating emission reduction credits (ERCs), verified emission reductions (VERs), and renewable energy credits (RECs) through improved quantification of the entire portfolio of benefits generated by biomass management projects, including reductions in dairy methane and nitrous oxide emissions, improved measurement of bioenergy production and conventional power displacement, and ammonia emission reduction and associated PM10 and PM2.5 reductions.

Introduction to the Model

The MANURE tool allows a user to enter general information about a specific dairy or swine livestock operation, as well as details about the practices used to manage manure produced by the farm. This information is saved in a scenario as the user progresses through the tool.

The user is prompted to enter a name and description for their scenario, select the year basis for the analysis, and enter specific climate information for that year. The year basis is the calendar year for which the analysis will be completed. For example, a user may run a scenario for 2007 to determine what emissions would have occurred under baseline conditions (i.e., the manure management practices in use prior to the installation of the project) and to determine what emissions actually occurred after implementation of the project.

In subsequent pages, the user is prompted to enter additional animal and manure management details for their farm that will allow the tool to estimate greenhouse gas reductions for a given year of operations at the farm. The tool will report on the mass of greenhouse gas emissions reductions associated with the scenario. View documentation of the calculations performed by the tool. (PDF file, 69K)

At any time, the user may return to their list of saved scenarios by clicking the Home link at the top of the screen. For questions on the use of this tool, click the Contact Us link at the top of the screen. A glossary of terms used through the tool can be accessed via the Glossary link. Finally, users may update their user name, password, and identification information by clicking the User Info link.

Site developed by Eastern Research Group, Inc. in conjunction with ERT-Winrock International

Version 1.2, May 15, 2009