Conduction Cooling Systems: Improving Production in Dairy Cattle

Research Year: 
2011
Issue: 

Arizona currently ranks in the top five in milk production per dairy cow. Yet heat stress during the warmest months causes decreases in milk yield and reproductive efficiency while increasing the incidence of disease and the maintenance costs per cow. Research has shown that compared to winter months, dairy cows in Arizona produced 8.8 pounds less milk per cow per day during the summer months. At the same time, on-farm milk production has the greatest opportunity to affect the carbon footprint of a gallon of milk because dairy operations represent 80 to 95 percent of the dairy industry’s carbon footprint, and 75 percent of its electricity and fuel use. Studies at the UA College of Agriculture and Life Sciences have focused on ways to minimize heat gain and maximize heat loss in dairy cattle to maintain or improve yields, while reducing water and electricity costs

Description of Action: 

A prototype conduction cooling system with an array of heat exchanger 'panels' installed beneath--rather than above--the cows' bedding area in dairy barns may result in a savings in electricity costs and water usage when used in combination with fans and misters, holding pen cooling and feed line soakers. Phase one proof-of-concept testing on the heat exchanger cooling system was conducted in June, 2010 at the UA’s Agricultural Research Complex in Tucson, followed by a commercial scale test at a 3,600-cow dairy located in Tulare, California in September 2010. The target temperature range for the cow is 100 to 103 degrees F, which the test system was able to achieve until the air temperature exceeded 90 degrees Fahrenheit.

In 2011 a multi-state research team was formed, led by UA Animal Sciences, with Agricultural and Biosystems engineering faculty from the UA, Biological and Environmental Engineering faculty from Cornell University, and Biological and Agricultural Engineering faculty from Kansas State University. This group is currently in negotiation with GEA, the world’s largest dairy equipment supply company to develop a research program to bring a commercially viable conductive cooling system to the world dairy industry. Funding has been obtained from the Water, Environmental and Energy Solutions program to begin mathematical modeling of a functional conductive cooling system and to build a test model to verify the computations. Further studies using conduction cooling systems were held in Arizona, California and Texas in 2012. Currently, the test model is being run in the controlled environmental rooms in the William Parker Agricultural Research Complex at the Campbell Research Farms. Once, these are completed a full study will be run at a commercial dairy in summer, 2013.

Impact: 

The new fan and mister system shows promise in reducing core body temperature and increasing resting time. Stabilizing core body temperature is critical if the goal is to improve the efficiently of milk production. By using conduction cooling alone to cool cows up to 90 degrees F, this same 3,600-cow dairy using 180 fans at 1.2 kilowatt hours per fan and paying $.09 per kilowatt hour would save a projected $26,500 for the summer in energy costs to cool cows—a savings of over 75 percent in electricity costs. The investigators believe that if the water had been chilled by a commercial chiller the electrical costs savings still would have been substantial, and there would have been additional milk yield benefits. The multi-state research team is to develop models of cooling systems that could run successfully with different water and air temperatures.

Conact Name: 
Robert Collier
Contact E-mail: