Sub-Wet Bulb Evaporative Chiller Conduction Cooling

Technology Description

Sub-Wet Bulb Evaporative Chiller Conduction Cooling

Technology Description

Bedding area beneath the cow is cooled using heat exchange mats embedded in the soil. Water flowing through the heat exchange mats will be chilled using a novel low-energy sub-wet bulb evaporative chiller. (SWEC).

Technology Stage

R&D Early Stages/Testing

Technology Application(s)

The majority of California’s dairy farms are located in the Central Valley, where summers are very hot and dry. Their milk cows need to be cooled both for health and productivity reasons

California dairy farmers rely mainly on various forms of forced convection and evaporative cooling systems such as large circulation fans and high-water-volume feed lane soaking systems. These systems work by enhancing convective heat transfer and reducing the ambient air temperature through the evaporation of water.

Current systems require significant amounts of water and electricity.

Technology Benefits:

  1. Infographic: Cow Cooling Approaches

    Builds drought resilience by reducing the amount of water needed to cool California’s 1.78 million milk cows.

    • The proposed conduction cooling has the potential to reduce water consumption by 73% as compared to current soaker systems.
    • An implementation in 10% of dairies equates to 4990 acre-feet of water savings per year.
  2. Supports electric reliability:
    • Reduces electric consumption (kWh) - Conduction Cooling has the potential to reduce electricity use by 38%.
    • An implementation in 10% of dairies equates to approximately 7.5 million kWh of electricity savings.
  3. Reduces greenhouse gas emissions:
    • Production of “Integrated Distributed Energy Resources” (IDER: energy efficiency, demand reduction, distributed renewable energy production) all reduce greenhouse gas emissions:
      • Reducing electric use and electric demand reduce production and/or purchase of marginal electric resources, much of which is produced by natural gas.
  4. Reduces ratepayer costs:
    • IDER reduces costs and risks to electric reliability, reducing electric costs for all ratepayers
  5. Reduces regulatory and environmental risks

Current Status

This project consists of two phases. In Phase I, to be performed in the UC Davis dairy, the Conduction cooling approach is demonstrated in a comparative study with the Targeted Convection Cooling approach. (Details for the TCC approach are contained in a different profile). In Phase II, to be performed in a commercial dairy in Tulare, the best performing approach from Phase I will be installed and monitored over a period of two 6-month summer periods.

Data provided by Grant Request Form on