The Lighting Research Center (LRC) at Rensselaer Polytechnic Institute recently released a guide for designing light scoops—an innovative skylight design developed by the LRC with funding from the New York State Energy Research and Development Authority (NYSERDA). Light scoops provide optimal levels of daylight throughout the changing seasons and daily fluctuations in weather by capturing and strategically redirecting daylight into buildings.
Many conventional horizontal skylights provide too much sun on days that are warm and sunny, and too little sun on days that are cold and dark. The LRC’s new skylight design balances out these daily and seasonal fluctuations in light level and temperature by providing less light in summer and more light in winter, while accounting for the natural pattern of the sun as it travels across the sky. In overcast conditions, a light scoop receives light from the brightest part of the sky, known as the zenith. Light scoops are most appropriate for spaces where direct sun is desirable such as lobbies, cafeterias, and hallways. They work very well in locations that are frequently cloudy and overcast such as Seattle, Portland, Detroit, and Buffalo.
Using light scoops and controls, electric lights can be turned off or dimmed when adequate daylight is available, thus saving energy and operating costs. Light scoops can also save heating and cooling energy.
Not only does this new skylight design save energy and operating costs, but it provides occupants with a more pleasant environment. Light scoops provide “patches of sun” where occupants can enjoy the health benefits of sunlight. In 2012, 14 light scoops were installed on an expansion of the Welch Allyn corporate headquarters in Skaneateles, N.Y. Several months after the light scoops were installed, 48 occupants completed a survey with a very high rate of satisfaction—almost 90 percent “like” or “strongly like” the patches of sun in the atrium. More details of the Welch Allyn installation and case study can be found in the Light Scoops design guide.
Light Scoops: A Design Guidedemonstrates how to design light scoops to meet target light levels and includes a performance comparison of light scoops vs. conventional skylights.