Energy standards implemented by the Department of Energy (DOE) and the Energy Policy Act of 2005 largely eliminated the manufacture and importation of fluorescent T12 magnetic ballasts in 2010, and new DOE standards will eliminate many popular 4- and 8-foot T12 lamps in 2012. As distributors offload their inventories, owners of T12 lighting systems will be looking to experts to help them identify compliant options. What are the options?
The T12 option
Last September’s lighting column centered on lamp and ballast energy standards and the resulting impact on product availability, concluding that owners of T12 lighting systems—and the electrical contractors that serve them—should explore opportunities to upgrade to T8 systems. There is, however, a T12 alternative that deserves some discussion, created by rule exemptions.
Several lamp types are exempt from the DOE fluorescent lamp rules going into effect on July 14, 2012, including F96T12HO lamps rated for cold-temperature applications (below 60°F) and some specialty lamp types, such as ultraviolet lamps. A significant exemption, however, is granted for lamps with a color-rendering index (CRI) rating of 87 or higher. High-CRI lamps are typically used in specialized color-critical applications and not in typical spaces, such as offices and schools, where a CRI greater than 80 is recommended.
While a majority of 4- and 8-foot T12 lamps will not comply with the DOE’s new energy standards, some lamps currently do because of the high CRI exemption. The major lamp manufacturers offer 4-foot, 34-watt (W) and 40W cool-white “deluxe” T12 lamps with a CRI of 87-plus. However, besides providing a CRI that is higher than recommended in most workspaces, these lamps produce lower light output than the most popular 4-foot T12 lamps. For example, a compliant 4-foot, 40W T12 produces about 2,200 lumens, and a compliant 4-foot, 34W T12 produces about 1,900 lumens, roughly 30 percent less light output than their lower CRI counterparts. While many older buildings featuring T12 lighting systems are overlighted relative to today’s recommended practice, a reduction in light level of this magnitude may disqualify these lamps from consideration in many projects. Further, if compliant high-CRI T12 lamps are selected as appropriate for the application, a mass lamp conversion is recommended to avoid mixing lamp types in the same space, which could negatively affect uniformity and space appearance.
At least one manufacturer offers several 4-foot, 34W and 40W T12 rapid-start bi-pin lamps that pass the energy standards without the high-CRI exemption and lower light output tradeoff, based on the use of rare earth phosphors. It is also possible, based on demand, that manufacturers may come up with additional higher lumen, high-CRI options by the July 2012 deadline. However, rare-earth phosphors generally add cost to the lamp; therefore, the owner would have to evaluate this as part of the financial analysis.
On the ballast side, the above-mentioned lamps can be paired with T12 electronic ballasts, which pass the ballast energy standards and can generate up to 30 percent energy savings compared to magnetic ballasts, according to Philips Lighting Co. Electronic ballasts are available for operation of one and two 4-foot, 34W and 40W linear and U-shaped rapid-start lamps, one and two 8-foot, 60W and 75W F96T12 instant-start lamps, and one and two 95W and 110W F96T12HO rapid-start lamps.
Obviously, this enables owners to comply with current regulations and benefit from energy savings while retaining T12 lighting and enabling ballasts to be replaced individually as they fail instead of all at once with associated initial cost. To be clear, nothing is being kept by retaining T12 lighting; regardless of which technology is chosen, new lamps and ballasts will be required, with the difference for T12 being the ballasts (and in some cases the lamps) can be spot replaced over a period of years instead of all at once. This is likely to be attractive to owners that are highly averse to risk. However, the T12 option presents its own risks that should be understood.
The T12 option may produce good energy savings at its lowest wattages but presents an opportunity cost, as converting to T8 lighting saves even more energy and offers options for longer service life, which can also reduce maintenance cost. After regulations eliminate the most popular models from the market, owners should not automatically assume that T12 will be the lowest cost option. A financial analysis will reveal the most profitable path forward, with T8 being favored particularly when it includes future energy and maintenance costs and the impact of incentives, such as utility rebates and tax deductions.
Perhaps the most significant factor is that T12 may remain a target for future energy standards. According to one manufacturer, the DOE is currently working on new fluorescent ballast rules that will become effective in 2014 and may eliminate even more T12 options, with an additional rulemaking for fluorescent lamps also on the horizon, all of which may make T12 technology increasingly difficult to maintain in the long term.
In conclusion, the T12 option is on the table, but it is not necessarily the lowest risk option. Owners should conduct an analysis of their lighting needs and financial performance for all of their options and choose the one that delivers the greatest value.
The T8 option
The T8 lighting system, now the standard in new construction, offers the most energy-efficient replacement option for T12 systems, with the best opportunities being in buildings with high energy costs that have lighting that is frequently on all night, and with spaces that are overlighted.
According to the National Electrical Manufacturers Association (NEMA), T8 electronic ballasts represented 60–65 percent of the total fluorescent ballast market in 2009, compared to 7 percent for T12 magnetic ballasts and 5 percent for T12 electronic ballasts. T8 lamps, meanwhile, outsold T12 lamps 3-to-2.
LED replacement lamps
In today’s lighting industry, there currently is a push to replace linear 4-foot fluorescent T8 and T12 lamps with linear light-emitting diode (LED) lamps in existing fixtures, but evidence suggests these products may not yet be ready for mainstream general lighting applications.
Four products introduced at the 2010 Lightfair included 17–25W T8 lamps producing 1,200–1,850 lumens, able to work with or without the existing ballast. The advantages, say manufacturers, include energy savings, long life, no mercury or lead, and resistance to shock and vibration. A two-lamp LED system with two 18W lamps would reduce energy consumption by 75 percent if replacing two 34W T12 lamps on an energy-efficient magnetic ballast and 40 percent if replacing two 32W T8 lamps on an electronic ballast. With a 50,000-hour-rated life, the LED lamps could potentially provide years of service.
The problem is DOE (CALiPER) testing of 12 LED replacement lamp products going back several years suggests poor performance and low levels of light output and efficacy, expressed as lumens/W. While it is true the LED lamps are directional, which improves fixture efficiency, this is not enough to achieve comparable light levels. At the same time, it presents a potential tradeoff in fixture distribution, which could affect uniformity of light levels. Round 11 of testing showed improvement in efficacy but continuing problems with light distribution, color quality and reliability. With a typical cost of $50 to more than $100 per lamp, this retrofit option can be difficult to justify economically, particularly as T8 lamps offer options for extended service life. The greatest value is where the LED lamps can deliver distinct advantages, such operating in very cold temperatures. —C.D.
Options include 23W, 25W, 28W, 30W, standard-output 32W and high-lumen T8 (Super T8) lamps, and extended-life T8 lamps operated on basic-grade and NEMA Premium high-efficiency electronic ballasts.
Suppose we have a recessed troffer with four 34W T12 lamps powered by two 0.88 ballast factor (BF) energy--saving magnetic ballasts for a total of 144W. If we need roughly the same light output, one option is a four-lamp 32W T8 system powered by a single NEMA Premium low-power (0.77BF) electronic ballast for a total of 95W, reducing energy consumption by 34 percent. Another possibility is 28W or 30W T8 lamps on a ballast with the same characteristics for 38 and 43 percent energy savings, respectively. Also, you could use 25W lamps on a normal BF (0.87) ballast for 42 percent energy savings.
Many older buildings are overlighted compared to today’s recommended practice. If we can reduce light output, then we could use four 25W T8 lamps on a NEMA Premium low-power ballast for 48 percent energy savings with about a 13 percent reduction in light output.
For the most efficient fluorescent T8 electronic ballasts, look for the NEMA Premium Ballast mark on the labeling. These ballasts operated with at a 90–95 percent efficiency, producing 2–5W of power savings per ballast compared to standard T8 systems. When paired with energy-saving T8 lamps (25W, 28W, 30W), NEMA Premium Ballasts can generate more than 20 percent energy savings compared to standard T8 systems, with some reduction in light output. Most innovation in the T8 segment is focused on these ballasts.
For example, the major ballast manufacturers now offer parallel lamp operation for 1-, 2-, 3- and 4-lamp programmed-start ballasts. Parallel lamp operation provides independent lamp operation, meaning if one lamp fails, the others stay lit. Programmed-start operation maximizes lamp life in environments where the lamps are frequently switched, such as with occupancy sensor installations.
Other recent innovations include programmed-start ballasts that start the lamps faster, amalgam lamps that produce peak light output across a broader ambient temperature range, light level switching (step dimming), load-shed ballasts, and a great choice of ballast factors (include 1.0 and up to 1.18, depending on the model). Manufacturers, meanwhile, are now saying their energy-saving T8 lamps are dimmable.
When recommending an upgrade, be sure to consider maximizing energy savings with lighting control options. Many options are available that are suitable for existing buildings, including occupancy sensors, low-voltage relay panels, line-voltage dimming, wireless sensors and controls. If the lights are left on all night in a given existing building, installing simple automatic shutoff controls can save a lot of energy.
Finally, consider that, in some cases, the cost of replacing the lighting fixture may be comparable to replacing its components. New fixtures are available that use T8 or T5 lamping and can generate high levels of energy savings while improving lighting quality. Remember that a lighting upgrade is an opportunity to comprehensively address the lighting system, not just how much energy it uses. Many older systems were poorly designed, so upgrading creates opportunities to correct problems such as glare, visual fatigue, poor uniformity, shadows, flicker and gloomy atmosphere. This may involve a redesign of the lighting system. Choices include volumetric-distribution recessed fixtures, direct/indirect pendants, wall lighting and other possibilities. Clearly, electrical contractors have many options to help building owners replace and upgrade their lighting systems.
DILOUIE, a lighting industry journalist, analyst and marketing consultant, is principal of ZING Communications. He can be reached at www.zinginc.com.