UVM Extension Horizontal Banner - Cultivating Healthy Communities
UVM Extension helps individuals and communities put research-based knowledge to work.
TechUpdate
from the Agricultural Engineering Program
Greetings!

As you may know, UVM Extension has initiated an Agricultural Engineering program and I am very pleased to have been selected to lead it.  My job is to conduct research, technology development & transfer, applied engineering, education and outreach to support the development and enhancement of Vermont's small-scale food and agricultural systems.

I'm incredibly excited to have this opportunity to support Vermont's food systems and to continue working with farmers and other agricultural professionals throughout the state and beyond.

Some of the specific areas I expect to focus on initially include greenhouse energy efficiency, renewable fuels, post-harvest fruit and vegetable processing, enhanced refrigeration, and application of control technologies to food production. But I am very interested in hearing what technical challenges you think are most critical to you.  If you have a moment, send me your thoughts on where you think the most significant technical challenges are in your operation. My complete contact information is provided on the left hand side of the AgEng blogand at the bottom of this eNewsletter.

Below, I've highlighted a few items I think you might find interesting at this time of year.  The calculators listed are a sampling of others that are available on the AgEng blog.  It is a growing list, so check back often.  If you run into trouble with any of these resources, have questions on using them, or know of others that I should include please be in touch.

I have added you to my distribution list for this eNewsletter because I think you will be interested in receiving updates on our programming and research.  Please forward this along to others that may be interested in signing-up to receive future eNewsletters automatically. If you have a mailing list please feel free to share this email with that list. 

Chris Callahan, PE
UVM Extension
Howe Business Park - 1 Scale Ave, Suite 55
Rutland, VT 05701
802-773-3349 x277 -chris.callahan@uvm.edu
CoolBot(TM) Installation
CoolBots™ - A quick, simple and inexpensive cooler option.

Many growers who don't have walk-in coolers have expressed interest in CoolBot's. This type of system uses a common window unit air conditioner to create a refrigerated space to store food.  This is done by purchasing an add-on controller from the inventor of the CoolBot.  This controller, once wired into the air conditioner, modifies the way the unit works and allows it to cool to 32 F instead of the normal air conditioning limit of 60 F.

Learn more about CoolBots from the inventor...
 
Solar Charts

I've been asked lately for a way to easily determine the sun's Rutland Solar Chart position at various times of day and various times of year.  There is an easy to use tool from the University of Oregon for creating a chart for a specific location.

This type of chart can be handy for locating and designing new structures so they intentionally either shade or don't shade other structures.

Make a sun chart for your location...

Solar Water Pumping

Check out this great little blog article on solar water pumping that the New Farmer project pulled together.  It was nice to be able to help out a bit on the pipe pressure loss and pump sizing parts of it.

Estimating Heat Loss & Heat Load

Is it getting chilly outside or is it me? One of the most important parts of installing or upgrading heating systems is estimating the heat loss of the structure being heated.  An undersized heater will lead to a poorly heated space and an oversized unit will waste fuel by cycling on and off too frequently. There are a number of full-fledged heat loss programs available but many are quite complicated.  I recently came across a very simple heat loss calculator that provides a first-pass estimate in short order.

Image courtesy of UGA pub B792
.
In important note: This calculator assumes an internal temperature of 70 degF which is not common in agricultural buildings. (I've asked the author to consider a revision allowing the user to input this value.) Luckily, the important design factor in heat loss is the temperature difference between inside and outside.  So you can account for different inside temperatures by adjusting the input outside temperature. For example if you're heating to 55 degF against a -5 degF outside design temperature (60 degF difference), set your outside temperature in this calculator to 10 degF (70 degF minus 60 degF).