Penn State University Department of Agricoltural and Biological Engineering Authors: Gustavo G.T. Camargo, Matt R. Ryan, Tom L. Richard Farm Energy Analysis Tool (FEAT)

PURPOSE The Farm Energy Analysis Tool (FEAT) is a model that estimates the energy consumption and greenhouse gas (GHG) emissions for a large variety of agricultural systems.

STRUCTURE FEAT is a tool implemented in Microsoft Excel to store data, perform calculations, and present graphs. The program is divided into 4 worksheets: 1) “AgInputs” (the agricoltural inputs and outputs) 2) “Energy” (the energy parameters for agricultural inputs and outputs) 3) “GHG” (the greenhouse gas emissions parameters for agricultural inputs and outputs) 4) “Crop” (the energy and GHG analysis for a cropping system in a year)

WHAT USERS DO In the “crop” worksheet there are 13 blue cells that correspond to the 13 different types of crop you can choose to grow. In each blue cell the user must insert the amount of hectares he is planning to allocate for each crop. This is the part in which the user “creates” his own farm.

To calculate the amount of energy (in Mega Joules per year) that each crop needs and the amount of GHG released, there are other inputs (highlighted in the green rectangle in the previous image), such as: yield, crop moisture at harvest, nitrogen fertilizer rates, phosphate rates, diesel fuel consumptions etc. which are already present in the program, but the user can modify them whenever he wants.

RESULTS Once the user has inserted the number of hectares, the calculations are made and you can see the results in the “Energy analysis” table and in the “Greenhouse gas emissions analysis” table. Pie charts also show you the amount of energy that each input requires.

LINK BETWEEN WORKSHEETS The “crop” worksheet can perform calculations because it relies on the fact that its cells are linked to the parameter values in the other three worksheets (“AgInputs”, “Energy” and “GHG”). For example: if the user wants to know where the values used to calculate the yield for Wheat come from, he just needs to click on the cell and look at the formula bar.

As you can see from the previous image the fomula bar tells the user that the yield is a function of a specific cell in the “AgInputs” worksheet (in this case B6) The user can now go to the “Aginputs” worksheet and find out that the value in B6 has been taken from the “PSU Agronomy Guide 2008”. The values used in the energy analysis and the GHG emissions analysis refer to cells in the “Energy” worksheet and in in the “GHG” worksheet.

The Greenhouse gas emissions are calculated in a very interesting way: All the inputs and outputs are converted to carbon dioxide equivalent. The main GHGs from agricultural production (CO2, CH4, and N2O) have different global warming potentials (GWP), this means that each GHG has a different impact in terms of global warming and GWP is used as a factor to equalize each gas. GHG EMISSIONS

CONCLUSIONS This program could be very useful to young farmers who are willing to start their own farm. Thanks to the energy consumption evaluations they would be able to calculate how much their activity will cost and decide which crops are the ones that cost less to grow. The authors of the program also used FEAT on a global scale and managed to estimate the energy consumptions and GHG emissions of entire countries, such as China, Brazil, Uganda and South Africa. Big countries could use this program to reduce their GHG emissions and plant crops wisely.