Department of Energy (DOE) regulations for general-service fluorescent lamps, which take effect July 14, 2012, strengthen standards established by the Energy Policy Act of 1992 while expanding coverage to include 8-ft. T8 lamps, 4-ft. T5 lamps and more wattages of 4-ft. T8 and T12 lamps. Aside from some exemptions, the regulations were expected to eliminate a majority of 4-ft. linear and 2-ft. U-shaped T12 lamps, many 8-ft. T12 and T12HO, and some lower-color-rendering 4-ft. T8 lamps.
As a result of the rare earth crisis, however, DOE recently granted a request by GE Lighting, Philips Lighting Company and OSRAM SYLVANIA to extend the effective date of the regulations for these companies’ lower-color-rendering 4-ft. T8 lamps by two years. The new effective date is now two years later, or July 14, 2014. This provides building owners a lower-cost option for applications where color rendering is less important, such as transition spaces, storage rooms and industrial applications.
Fluorescent lamps produce light through the process of fluorescence, in which electric current is passed through mercury vapor, resulting in the emission of UV radiation that is largely converted into visible white light by phosphors coating the lamp bulb. Application of rare earth phosphors, used in addition to or instead of traditional halophosphors, produce higher efficiency, color rendering and lumen maintenance. Five rare earth elements are used in phosphors for energy-efficient and high-color-rendering linear fluorescent lamps, primarily Yttrium, Europium and Terbium (which is why these lamps are sometimes called “triphosphor lamps”).
The problem is China currently controls more than 95 percent of the world’s supply. With demand increasing in recent years, China began limiting exports to ensure steady supply for its domestic industries, while increasing taxes and tariffs. As a result, prices skyrocketed—increasing at an annual rate of 400 and 500 percent respectively for Terbium and Europium oxides in 2011—forcing lamp manufacturers to announce a series of steep price increases for rare-earth phosphor lamps.
One manufacturer, OSRAM SYLVANIA, brought a halophosphor T8 lamp to market as a lower-cost option for building owners, but this product is expected to be discontinued July 14, 2012 as it does not comply with the fluorescent lamp regulations. By temporarily granting the lamp manufacturers’ request to exempt lower-color-rendering 4-ft. T8 lamps, building owners will enjoy another option suitable for some applications. These 700-series (color rendering index, or CRI, of 70+) T8 lamps contain 70 percent less phosphor content than 800-series (CRI of 80+) lamps. (For applications where color is important, a minimum of 80 CRI is recommended.)
A randomly selected 700-series product operates at 75 CRI and produces an initial 2,745 lumens, about seven percent less than a 2,950-lumen 800-series lamp, and 2,444 mean lumens, or 13 percent less than the same 800-series lamp (89 percent versus 95 percent lumen maintenance).
The increase in rare earth material prices is resulting in new sources being developed outside of China, but this will take time, and different mines do not yield the same quantities of various elements. According to the Department of Energy, Europium, Terbium and Yttrium will continue to see high risk to supply and cost uncertainty for the near future.
