The U.S. Department of Energy (DOE) recently issued new energy standards for general-service fluorescent lamps, and the standards go into effect Jan. 26, 2018. The new rules are likely to primarily affect availability of standard 4-foot, 32-watt (W) T8 lamps and some reduced-wattage T8 lamps. However, a full range of 8-foot T5 and exempted specialty lamps will continue to be available. The rules reflect ongoing federal energy policy favoring high-efficiency lighting while steadily removing the least-efficient, lowest cost products from the market.


The Energy Policy Act of 1992 regulated general-service fluorescent lamps and provided future regulatory authority to the DOE. In 2009, the DOE updated the rules to include 8-foot T8 and 4-foot T5 lamps as well as a broader range of 4-foot T8 and T12 lamps. These rules became effective in July 2012, eliminating a majority of 4-foot linear and 2-foot U-shaped T12 lamps and many 8-foot T12 and T12HO lamps.


Additionally, low-color-rendering (700 series, with a 70–79 CRI) 4-foot T8 lamps also did not comply, though the DOE granted a two-year exemption to certain manufacturers petitioning for temporary relief due to the rare earth crisis that increased costs and demand for 700-series lamps. That exemption expired July 2014.


The new rules strengthen existing energy standards, expressed as minimum efficacy (lumens per watt), for 4-foot medium bipin (aka, 4-foot linear T8), 2-foot U-shaped (aka, 2-foot U-bend T8), 4-foot miniature bipin (aka, 4-foot linear T5) and 4-foot miniature bipin high output (aka, 4-foot linear T5HO). Required minimum efficacy for T8 lamps increased modestly, about 1–4 percent, but up to the maximum technology level. Required efficacy for T5 lamps increased by about 7–10-plus percent. Eight-foot lamps did not see an increase in required efficacy.


The same exemptions apply, including lamps designed to promote plant growth, lamps designed specifically for cold-temperature applications, colored lamps, impact-resistant lamps, reflectorized or aperture lamps, lamps designed for reprographic applications, ultraviolet lamps, and lamps with a CRI of 87 or higher.


Manufacturers have three years to evaluate their products and either discontinue or re-engineer them on a case-by-case basis. Eliminations are expected, affecting availability and cost. After the effective date, distributors may continue to sell off their inventories of noncompliant lamps.


For the consumer, the DOE estimates the average payback of three to four years and cost savings with a cumulative net present value (including energy cost savings and increased purchase cost) of between $2 billion (7 percent discount rate) and $5.5 billion (3.3 percent discount rate) over the next 30 years. However, as the new lamps generally will not be instrumental in reducing number of luminaires, energy savings are only realized if switching from a full- to a reduced-wattage lamp or operating a full-wattage lamp on a control system capable of dimming.


The last round of energy standards eliminated a majority of T12 lamps from the market. The new standards will primarily fall on T8 and T5 lamps. Interviews with major lamp manufacturers revealed several likely outcomes.


For 4-foot T8 lamps, a majority (70 percent, according to one estimate) pass the new standards. However, these are primarily 25W, 28W and 30W lamps. Today’s basic-grade 32W T8 lamps do not comply. Lamps with lower color temperatures are disproportionately affected. The main choices will be more efficacious 25W, 28W, 30W and 32W lamps. Some standard 32W T8 lamps may be re-engineered, but the overall effect is predicted to be reduced availability. Extended-life lamps are expected to survive but may be limited to wattages lower than 32W unless manufacturers decide to re-engineer them to comply.


For 2-foot U-bend T8 lamps, again, about 70 percent pass. Again, many 32W lamps do not comply; only the most efficacious options remain. Lamps with lower color temperatures are disproportionately affected. Some may be re-engineered, but, as with 4-foot T8 lamps, the net result will likely be reduced availability. 


Another problem is whether the lamp features 15/8-inch or 6-inch leg spacing. Most users of 6-inch leg spacing use full-wattage lamps on control systems so they can be dimmed, while users of lamps with 15/8-inch spacing use reduced-wattage lamps.


While minimum efficacy levels for 4-foot T5 and T5HO lamps increased significantly and a broader range of wattages are covered, a majority of products comply. Manufacturers interviewed expect that today’s products will satisfy the new rules with limited re-engineering.


Joseph G. Howley, manager, industry relations, GE Lighting, said: “While there are no changes expected in lamp availability during the next three years, a more limited number of 4-foot, 32W T8 lamps will be available in 2018. Distributors and contractors may wish to recommend that their customers switch to 28W or 25W 4-foot and U-bend T8 lamps unless the customer is using the lamps on full-range dimming systems.”


“Consumers will have fewer lamps to choose from,” said Susan Callahan, manager, energy relations, Osram Sylvania. “Lamps that comply will be more expensive; may not have the features customers prefer, such as long life; and, in many applications, provide lower light levels.”


For more information, contact lamp manufacturers directly.