Incandescent reflector lamps (IRLs) are the very common cone-shaped light bulbs most typically used in track lighting and "recessed can" light fixtures (low-cost light fixtures that mount flush with the ceiling such that the socket and bulb are recessed into the ceiling). The cone is lined with a reflective coating to direct the light. PAR lamps are the most common type of IRL; other common IRLs include "blown" PAR (BPAR) lamps, which are designed to be a low-cost substitute for widely used PAR lamps, and "bulged" reflector (BR) lamps. Use of BR lamps has ballooned over the past 15 years as manufacturers have taken advantage of a loophole that exempts them from federal standards.
In December 2007, Congress enacted EISA, which required DOE to extend the coverage of EPAct 1992 IRL standards to some previously exempted lamp types, effective June 2008. In June 2009, DOE issued a final rule amending the 1992 reflector lamp standards, although the most common lamp, a 65-watt BR lamp, and other various lamps at 50 watts and below were not included in the 2009 rule. The federal standard, which took effect in July 2012,set an efficacy level in lumens per watt (lpw) that can be achieved by halogen infrared (HIR) lamps incorporating improved reflectors, coatings, and filaments. Improved HIR technologies will increase average baseline efficacy from about 14 lpw to 19 lpw. As a result, average IRL wattage will drop from about 75W to 55W. According to DOE estimates, the 2009 standards will save up to 2.4 quads over 30 years. Over that same 30-year period, businesses and consumers will save up to $18 billion in net present value savings, and carbon dioxide emissions will be cut by up to 106 million metric tons.
Additional savings will come from extending the scope of the standard to cover the still-exempted lamps. In September 2011, DOE published the framework document for energy conservation standards for certain elliptical reflector (ER), bulged reflector (BR), and small diameter IRLs that were exempted from the 2009. A final rule, initially expected in 2012, was never published.
The 2012 ASAP/ACEEE report, The Efficiency Boom, analyzed an average 26 lumens per watt standard based on 2011 research by Ecos (now Ecova) on improved halogen infrared (HIR) technology. The analysis includes savings from standards covering all major classes of IRLs including those ER, BR, and other IRLs previously exempted from standards. Standards at this level are expected to produce annual savings in 2035 of 20 TWh and generate $11 billion in net present value savings for consumers.
Like other incandescent lamps, HIR lamps utilize a tungsten filament, but the filament in HIR lamps is surrounded by a capsule filled with a halogen gas while the glass is coated with a material that reflects infrared light. Introducing a halogen gas and an infrared coating to an IRL increases the efficacy of the bulb in several ways. By reflecting radiant energy, or heat, back onto the filament, the operating temperature increases, resulting in higher light output from a given wattage. The halogen gas increases the longevity of the filament by introducing a regenerative cycle, where the evaporated tungsten from the heated filament combines with the halogen gas to make a gaseous compound, which allows the tungsten to be re-deposited when the compound comes back into contact with the filament. Improved coatings and advanced reflector designs can further increase HIR lamp efficacy and decrease annual electricity consumption of IRLs.