UVM Extension Ag Engineering

This planning tool is intended to help growers estimate storage space, temperature and humidity conditions, grouping and product heat load.  It has been developed using published data from several sources including USDA Handbook 66 [1].  It is provided as a beta release and your feedback is welcome.  I am particularly interested in feedback on the bulk density of various crops and even varieties that you are growing (i.e. how many pounds of a product are in a bushel or other volume measure.)  I have used what data I could find, but some of it does not seem well-aligned with actual practice.  Help me improve this tool by letting me know where it could be better.

Download the tool: UVM Extension Crop Storage Planning Tool.

NOTE: This spreadsheet uses macros to make your life easier.  Excel will likely prompt you with a security warning about this.

Instructions:

1. Start with a list of the crops you plan to store and a rough idea of how much you plan to store (in pounds or tons).  These can be estimated from row feet using Knott’s Handbook [2], Rutgers University Guide [3], seed companies or other sources.
2. On the Inputs tab of the spreadsheet planner, enter the amount of each crop you plan to store.
3. Click the “Go to Outputs” Button at the top of the Inputs tab, or navigate to the Outputs tab.
4. You may have to Refresh the table (pivot table).  If you have entered something that isn’t appearing, press Alt-F5 to refresh the planner.
5. Your crops will be grouped by storage zone (a grouping of crops based on similar temperature and humidity conditions).
6. The other information presented includes:
   1. Temperature and Humidity – These are the ideal conditions for optimal quality preservation during storage, taken mainly from USDA Handbook 66.
   2. Product Respiration Heat Load – This is the heat addition to the room from the product as it respires.  This can be helpful for determining the refrigeration or cooling load required.  NOTE: The heating or cooling load of the room will also depend on the construction (Surface area, R-value, etc.) and outside temperature.
   3. Sum of Product Volume – This is the total volume taken up, when stacked in bulk, by the product.  It doesn’t account for containerized stacking, open space for ventilation, space for people and product movement, etc.
   4. Sum of Total Volume of Space – This is the estimated volume of the space allowing for 1/3 of the space being open for air flow, people and product movement, etc.
   5. Sum of Square Footage at 8 foot height – This is an estimate of the floor space required in the room to store the volume of product (including the 1/3 open space) assuming an 8 foot height.
   6. Note that all of these figures are totaled by storage zone (group) to help plan for different rooms and zones.