Jim Benya diagrams lamp ballast efficacy—the efficiency based on mean lumens per watt—using current market product offerings.
Jim Benya diagrams lamp ballast efficacy—the efficiency based on mean lumens per watt—using current market product offerings.

Based on the innovations in lamps and ballasts since our last report (“Lighting's Latest Nuts and Bolts,” March 2008), the economy has not slowed the push to develop new products in these categories. Of course, new LED offerings are being introduced with greater frequency as they become serious product contenders, but there are a bounty of developments in regular lamps that still deserve attention.

TUNGSTEN The good ol' incandescent lamp is on its last legs. Despite rumors of a high-efficacy version, the only way to significantly improve the efficiency of an incandescent is to use relatively expensive technology such as the halogen cycle (a complex chemical interaction between tungsten, oxygen, and a halide), infrared reflecting coatings, and rare backfill gas. Tungsten may be nearing the end of the line unless a breakthrough is achieved. The worldwide movement to ban the bulb has abated slightly, but don't plan on being able to buy them 10 years from now.

But there are a few applications where tungsten lamps are still king and new products are still emerging. The principal developments are mostly in halogen and halogen IR projector lamps, where reflector design allows lower wattage while maintaining beam candlepower. Across manufacturers, the 45W to 48W PAR30, the 45W to 55W PAR38, and the aluminum-reflector 300W PAR56 and 1000W PAR64 are all examples of meaningful improvements.

COMPACT FLUORESCENT While we wait for sound LED options for incandescent replacement lamps, compact fluorescent lamps (CFLs) are still the cost-effective, energy-efficient alternative for many traditional incandescent applications. A steady flow of innovations continues, with new state-of-the-art products including:

  • Spring-shaped lamps available in both medium screw and GU24 bases that are dimmable and smaller than ever, allowing more lumens in more places;
  • PAR-style, screw-based aluminum reflector lamps suitable for recessed downlight applications;
  • GU24 lamps in more sizes, shapes, and wattages; and
  • Colored screw-based CFLs for use as party lights, bug lights, black lights, and other playful applications.

There is a special family of CFL lamps that uses cold cathode technology. Cold cathode is a type of fluorescent lamp with significantly increased lamp life; the lamps are rated at 25,000 hours. Use them when the design requires sources that last longer and can be easily dimmed or frequently switched, such as in flashing and chasing marquees.
Pin-based CFLsystems have not enjoyed nearly as much innovation, since this market is already established. The most important new products appear to be additions to ballast choices, particularly universal voltage dimming types for both analog and digital control systems. Other improvements include some lamps being rated up to 20,000 hours, including some new triple tube products.

COMMERCIAL AND INDUSTRIAL FLUORESCENT SOURCES Fluorescent lighting is still the most efficient and cost-effective lighting option on the market, and you can bet it will remain this way for a while. As a result, ongoing lamp and ballast improvements have resulted in some important new products.

One trend is lamps with superior life. Most companies offer T8 lamps with a rated life of up to 46,000 hours, equal to or better than the 70 percent lumen maintenance rated life of many LED products. Others have reduced mercury content and/or a number of reduced wattage variations. The most significant new lamp is the reduced wattage T5HO, the latest version needing only 49W to 50W to produce light levels similar to the original 54W lamp. At least one manufacturer now claims their low-mercury T8 lamps need no burn-in time for dimming operation.

Ballasts also continue to evolve and improve. A wide variety of universal voltage ballasts for T5 and T8 lamps are now available, including high-efficiency versions of instant-start and program-start types for one, two, three, and four lamps at high, normal, or low ballast factors. There are high-efficiency ballasts for F86T8HO and other less-popular lamps. A new generation of low-cost, multilevel ballasts use two switches to select off (both switches off), low (one switch off), medium (other switch off), and high (both switches on). Another uses a single switch to toggle between low and high light levels (to meet the EPACT 2005 tax deduction requirement in existing buildings with single switches). Among dimming ballasts, the latest include “high-efficiency” dimming ballasts that save several watts compared to standard dimming ballasts, and dimming ballasts with both “high-light output” and “low-light output” as well as standard versions. DALI and other digital ballast families also now include more lamp types and operate on all voltages.

INDUCTION LAMPS Now that costs for lamps and exciters are more competitive, there is a minor renaissance in fluorescent induction lamps. Also called electrodeless fluorescent, these lamps use the same principle of mercury discharge and phosphor emission of visible light as other fluorescent lamps, but are excited by radio waves from a transmitter instead of by the electrodes of a ballast. Low-wattage screw-based induction lamps last two to three times longer than regular CFLs, and the higher wattage sources—lamp life of up to 100,000 hours—make these appealing for locations that are hard to maintain. Their primary limitation is large source size, which forces larger luminaires, but nonetheless there are quite a few choices as manufacturers have recently introduced downlights, high-bay area lights, and outdoor luminaires, just to name a few.