The Energy Policy and Conservation Act of 1975 and its subsequent amendments established minimum efficiency standards for lighting products. While the DOE’s mandatory energy efficiency standards and recently-heightened surveillance efforts are designed to ensure manufacturers’ compliance with minimum U.S. energy efficiency requirements, they do not account for all of the “green” lighting certification programs and initiatives active in the U.S. and Canadian markets today.
A number of other voluntary initiatives – including the EPA’s ENERGY STAR® lighting certification program, the Lighting Facts labeling and packaging standard, and energy-efficient lighting initiatives by such organizations as DesignLights Consortium (DLC), the California Energy Commission (CEC), National Resources Canada (NRCan), and the Municipal Solid-State Street Lighting Consortium (MSSL) – are enabling energy-saving lighting products to meet additional sets of efficiency standards.
Energy-Efficient Lighting Certification Programs
The U.S. energy crisis of the 1970s was a key event that drew national attention to our country’s escalating consumption of energy. That led to the growth of initiatives designed to improve energy efficiency and curb demand. As examples, the emergence of utility incentives on more energy-saving lighting technologies in the 1980s and 1990s helped shift market demand to higher-efficiency products, while legislative efforts such as the federal Energy Independence and Security Act (EISA) of 2007 helped to force a shift in the manufacture and use of more energy-efficient lighting technologies such as T8 and T5 fluorescent lamps, electronic ballasts, compact fluorescent lamps, electronic HID, induction lighting, and LEDs.
Such economic, legislative, and societal forces helped spur additional investments in R&D and advances in lighting technology, which led to recent improvements in fluorescent, halogen, and HID technology. From this also came the growth and rapid evolution of solid-state lighting and LED technology. As part of its evolution, LEDs and their many component parts have amassed a growing list of considerations and requirements from a variety of vested stakeholders (Figure 1). These considerations range from performance standards related to distribution, color, and longevity, to operating requirements in unique locales such as roadways and hazardous locations, as well as compatibility with specific lighting controls and adherence to FCC electronic noise standards.
Performance Testing for Lighting Products
While reputable manufacturers typically participate in mandatory safety testing to enable their products’ retail sale in recognized establishments, performance testing is not mandatory for installation. Instead, it addresses how a product will perform when used by a consumer. Throughout the lighting industry, comprehensive performance testing typically consists of assessments in three different, universally-accepted areas: distribution, color, and stress/longevity.
Distribution Testing – this type of performance testing measures the light pattern out of a fixture or its total light output at all different angles. For all light sources, the most accurate means of measuring a light’s distribution is through the use of a Type-C Goniometer (Figure 2), a piece of equipment used to test most residential and commercial lighting products while enabling fixtures to rotate in a horizontal plane to measure their entire light distribution. IES standard LM-63 specifies how the results of a distribution test should be formatted and will typically require a text file showing all lighting values at each angle.
Color Testing – this type of performance testing measures the energy of light at each wavelength and is used to calculate color temperature. The most accurate means of measuring a light’s color is through the use of an Integrating Sphere-Spectrometer system (Figure 3), a specially-coated apparatus most commonly available in 1, 2, and 3-meter sizes that collects a light’s energy and measures it at all wavelengths. Measurements with such systems typically include lumen or brightness level, correlated color temperature (CCT) in Kelvins ranging from 2700-6500 for consumers, color rendering index (CRI), which measures how “true” a color looks under the subject lighting, and such other performance measures as chromaticity, which is a coordinate mapping of the light’s color.