05/30/2024

HVLS Fans v. Conventional High-Speed Recirculation Fans in a Dairy Barn

When considering an air circulation strategy for a dairy barn, there are a few strategies we see producers using.

  1. Conventional High-Speed Recirculation Fans
  2. HVLS (High- Volume, Low Speed) Fans

So, which is best? The answer is subjective, and many factors play into the effectiveness of each strategy.

HVLS fans consume less energy and operate more quietly than conventional high-speed recirculation fans, however, their cooling effectiveness in a dairy free-stall/pack barn located in a hot, humid climate is limited. A producer should consider the location of their barn and the climate in which they are in. If the goal of an air circulation strategy is to cool cows and increase milk production, the result of an HVLS Fan strategy could prove disappointing. HVLS fans generate low airspeed at cow and ground level. Designed primarily to recirculate large volumes of air at lower RPMs, farmers who install these fans with the expectation of “cow cooling” often end up disappointed with their barn environment and milk production. The effectiveness of HVLS fans heavily depends on the climate.

Conventional recirculation fans will likely consume more energy than HVLS fans. They will be louder. They will also provide more velocity for the herd. Cow comfort is a buzz word in the industry. Numerous studies have shown that keeping cows cool and increasing cows’ lying time has a positive impact on milk production. J&D encourages producers to use anemometers to test the velocity at cow level and see the difference high velocity, especially in summer months, makes on milk production.

Case Study: Kentmere Farms

Year: 2019
Location: Virginia
Air Circulation Strategy: HVLS Fans

Kentmere Farms installed approximately 12 HVLS fans in three of their pack barns to help with cooling and drying the bed pack material. These HVLS fans produced a wind speed on average of 1-2 mph at cow level (5 feet from the ground) and even less at ground level. This resulted in high humidity levels and no increase in milk production.

Frustrated with the environment in their barns, Kentmere Farms worked with Dairymen Specialty and ultimately J&D Manufacturing to assess the barn and the airflow conditions created by the HVLS fans. We identified the need to achieve air speeds of 5-7 mph at 1 foot from the ground to make a significant difference in the barn, ensuring drier bed pack material and effectively cooling the cows to boost milk production.

Within a few weeks of installing 12 AirBlaster fans in barn #1, Kentmere’s ownership immediately noticed the impact of higher air velocity on the bed pack material and milk production. Humidity in the barn dropped, the bedding material dried up instantly, allowing for better litter management, and the cows’ lying time increased.

Since then, Kentmere Farms has purchased 34 more AirBlasters and removed all HVLS fans from barns 2 and 3. Utilizing J&D’s Pulse Controller, the owners can now operate their fans year-round with the AirBlaster’s variable speed motors. In the cooler months, the speed of the fans can be decreased, saving energy, while still providing enough velocity to keep bedding dry but not blowing a harsh draft on the cows.

J&D is thrilled Kentmere Farms put their trust in our recommendation. The results speak for themselves. If you are not happy with the environment in your barn, please reach out to the ventilation experts at J&D Manufacturing for help. We’re passionate about creating comfortable environments where cows can thrive, and helping producers achieve their production goals.