Arlington, VA; March 6, 2012 —The Cooperative Research Network led one of the first major LED demonstrations at a dairy farm and got some surprising results: cows may produce more milk under LED lighting.

CRN designed a study to test the viability of solid state lighting (SSL) at a dairy farm that replaced half of the 250-watt metal halide lamps in a 120-cow freestall barn with 120-watt LED fixtures.

While researchers were expecting the efficiency gains, they were not expecting to see any changes in milk production but the cows under the LED lights produced more milk.

Over 12 months, the project validated a 55 percent reduction in energy use while providing a 50 percent increase in average lighting levels and a 61 percent improvement in uniformity, producing fewer of the shadows and dark areas cows dislike.

CRN will be conducting further research to confirm these findings and explore what might be behind the behavior change. On the human side of things, the brighter, more uniform LED light made it easier and safer for farm personnel to tend the cattle and equipment.

The LEDs produced more and better light with substantial energy savings. The LEDs also saved about 200 tons of CO2 emissions per year.

LED lighting systems are proving ideal for agricultural use. They are now the longest-lasting lights commercially available to farmers. With a rated lifetime of up to 50,000 hours, LEDs can last up to 33 times longer than incandescents, 4–8 times longer than linear fluorescent and compact fluorescent lamps (CFLs), and 2½ times longer than high-watt high-intensity discharge (HID) lamps, the large gas-filled glass bulbs common in street lights.