long day lighting
n.— «In regards to dairy farms, Reisenauer indicated many operators are doing a practice called “long day lighting” in which cows are exposed to 16-18 hours of light a day, year round, relying on a combination of natural and supplemental lighting. Although this may consume slightly more energy for lighting, he indicated most dairy producers are experiencing production gains ranging from 5 to 15 percent more milk, which more than offsets the energy costs.» —“Farm energy audit can help conserve energy and lower costs” by Dale Hildebrant in Grand Forks Farm & Ranch Guide (Bismarck, North Dakota) Feb. 2, 2008. (source: Double-Tongued Dictionary)