Balancing energy efficiency with employee comfort — making a case for lighting control systems in government buildings
Lighting in government facilities, both new construction and major renovation, is typically specified to help create the most efficient spaces possible.
Driven by regulatory and market forces, including the Energy Policy Act of 2005, which mandates energy reductions of 30 percent in federal government facilities by 2015 (compared to 2003 baseline), the lighting industry has refined lamp technology to deliver highly efficient fluorescent lamps and ballasts, and an ever-expanding offering of LED lamps, fixtures and drivers that deliver high lumens at low wattage.
Now that lamps, ballasts and fixtures are so efficient, it is critical to start thinking in terms of a complete system approach – including fixtures and controls on every project to further reduce energy costs, deliver return on investment of 3-5 years, provide easy retrofit solutions and ensure a comfortable space for building occupants.
Many municipalities have aggressive energy-saving goals for new buildings and major renovations. Because lighting typically accounts for 39 percent of the energy use in a commercial building, it also represents the greatest opportunity for energy savings, according to the Energy Information Administration (http://www.eia.gov/consumption/commercial).
More efficient lamps are a great place to start, but as lamp efficiencies approach the limits of technology, other strategies will have to be used to help drive continued reductions in lighting energy use. Lighting control systems that incorporate occupancy sensors, daylight sensors, personal control and even automated shading systems can help bridge this gap.
Dimming your lights, whether they are fluorescent, incandescent or newer LED lamps saves energy at a roughly 1:1 ratio. This means that if you dim LEDs down to 50 percent of their light output you will save nearly 50 percent of your energy usage and enhance the life of the lamp. Even if you are using highly efficient sources, you save even more energy by dimming them.
Implementing multiple automatic control strategies — such as occupancy sensors, daylight sensors, high-end trim and scheduling – can yield even greater savings in lighting energy. In the Chicago Police Station (12th District), occupancy sensors ensure that lights are off when an area is unoccupied, and daylight sensors allow electric light levels to be automatically reduced when daylight is sufficient for the officers to do their jobs. Similar lighting control strategies are used in the California Lottery headquarters to ensure that the city is not paying for wasted lighting electricity.
Government facilities have historically been cautious about installing wireless controls, but this is quickly changing as several large installations such as the Albuquerque Convention Center, Lane County Department of Public Works and the Homer Township Public Library have embraced the ease of installation and the attractive return on investment offered by wireless lighting control systems.
The cost of people is another critical consideration for every public facility. Your employees are your most valuable resource, and as budget pressures bear down on virtually every municipality, it is increasingly important to improve morale, enhance productivity, help to reduce absenteeism and to improve the productivity of your existing workforce.
Lighting control allows building occupants to control their own environment and set the right level for their specific tasks – balancing lighting efficiency with the optimal working environment delivers greater value to every government facility.
Andrew Wakefield is director of government solutions for Lutron Electronics, a U.S.-based company that designs and manufacturers more than 16,000 energy-saving products, sold in more than 100 countries.