General Service Fluorescent Lamps
Fluorescent linear lamps have a low pressure mercury electric-discharge source in which a fluorescing coating transforms some of the ultraviolet energy generated by the mercury discharge into light. Fluorescent lamps are manufactured in a variety of shapes (straight- or U-shaped) and types (rapid start and instant start). General service or linear fluorescent lamps are those lamps that satisfy the majority of fluorescent applications, except for some specific lighting applications, such as lamps used in horticulture, cold temperature installations, and others. Common fluorescent lamps include T12 lamps (T12 lamps have a 1.5-inch diameter), T8 lamps (1-inch diameter) and T5 lamps (5/8-inch diameter).
Initial standards for linear fluorescent lamps were enacted by Congress in the Energy Policy Act of 1992, building on standards developed by states. DOE updated the standards in June 2009, and the standards went into effect on July 14, 2012. The efficiency standards vary by type of lamp. The standard for the most common lamp type—4-foot medium bipin, ≤4500K—is 89 lumens per watt. The new standards can be met by 800 Series T8 lamps, which are more efficient than 700 Series T8 lamps. However, 800 Series T8 lamps require significant quantities of three specific rare earth oxides to produce the phosphor coatings, and these rare earth oxides have recently been subject to significant supply constraints. Due to this market disruption, many manufacturers of linear fluorescent lamps applied for and were granted exception relief. The exception relief allows these manufacturers to continue to produce 700 Series T8 lamps for a period of two years.
The new standards correspond to Trial Standard Level 4 (TSL 4) from DOE's 2009 analysis of standards options. The 2012 ASAP/ACEEE report, The Efficiency Boom, analyzed potential future standards based on TSL 5 from the same DOE analysis. For the 4-foot medium bipin, ≤4500K, the potential future standard is 93 lumens per watt. Across covered product classes, the potential standard represents savings of approximately 3.5% on a sales-weighted basis. DOE’s analysis showed that TSL 5 was technically feasible and yielded economic benefits for the vast majority of consumers. The average incremental cost is $0.75, and results in a 2.5 year payback period.
Fluorescent lighting accounts for 60–70% of the total lighting electricity consumed by commercial and industrial buildings.
Standard Projected Savings
ASAP Press Releases
Timeline reflects state standards from 2001 to present; federal standards from inception to present.