Calculators

The dairy manure storage cost calculator was developed in 2008 to help farms perform a partial budget of an impermeable flexible cover and flare system. The farm inputs needed include the number of cows and heifers whose manure go into the manure storage, the surface area of the storage, and the farm's manure spreading cost. Carbon credits can also be included with the estimated metric tons of carbon dioxide equivalent that can be captured and combusted (note: the tool uses a global warming potential on a 100-year basis). The calculation will provide the average annual capital cost over the lifetime, the annual average precipitation avoided, the annual average land application savings, and estimate of the potential carbon credits.

1. The first tool is designed for use with Farm Ware 3.1 which was developed by the United States Environmental Protection Agency and is available for free download at www.epa.gov/agstar/resources/handbook.html. This analysis uses the outputs of Farm Ware 3.1 to conduct a financial analysis. This worksheet does not guide the user through the inputs required to conduct a Farm Ware assessment.
    
2. The second tool allows the user to input more detailed information about their specific anaerobic digestion project. The tool requires that the user possess information about the capital and operating costs for the project. It utilizes a variety of assumptions to create estimates of the biogas and electrical generation potential of the project.

The worksheets itemize the inputs that one would need to conduct an economic assessment of a biogas project. The inputs are designed for use with two Microsoft Excel spreadsheets.
The inputs are used to create proforma financial statements for the biogas project and to conduct a discounted cash flow analysis of the project. A basic understanding of financial concepts is required to understand and interpret the outputs of the spreadsheets. These tools should only be used for an initial analysis of a biogas project. A more thorough analysis is required to establish the expected profitability of the project.

Users should carefully consider the validity of the assumptions utilized in the assessment before making investment decisions. In other words, these tools should be used with caution and no warranty is made regarding the validity of outputs obtained and decisions made based upon the model. The assessment does not consider the impact of any taxes that may be generated or saved by the project. These values may significantly alter the profitability of the project. The spreadsheets do not currently consider inflation or allow for changing prices over time. These assumptions can be modified with modest alterations to the spreadsheets. The spreadsheet will not identify inappropriate units or entries that are unrealistic.