Learn more about managing energy efficiency at http://www.gundersenenvision.org/educational-programs
This is an example of wasted energy. The photo shows two canned, spotlights mounted in an atrium near roof windows (skylights) that are allowing sunlight to illuminate the same space. Utilizing the natural daylight for illumination of interior spaces is called daylighting. Daylighting is a natural way to reduce fossil fuel electricity use and its associated cost, health, and environmental impact. Of course, during the nighttime or on cloudy days, the spotlights will still be needed to serve their purpose.
When designing or retrofitting buildings, look for opportunities to schedule lighting for appropriate periods with your building automation system (B. A. S.) controls. Lighting systems can also be setup to operate on photo sensors that detect the amount of light present in the space so that they are only used when needed. At a minimum, staff may be able to manually adjust lighting levels for the current conditions. Remember to only use energy when you need it and where you need it … the rest is just waste.