The National Electrical Manufacturers Association (NEMA) launched the Premium Ballast program to identify the industry’s most efficient fluorescent fixed-output and dimmable electronic T8 ballasts, thereby providing a mechanism for market recognition and specification of these products.
Ballasts qualifying as NEMA Premium Ballasts are recognizable via a special mark on the label distinguishing these products as the most efficient T8 ballasts on the market.
As of the time of publication, Advance, OSRAM SYLVANIA, Universal Lighting Technologies and GE have achieved NEMA Premium Ballast certification for their high-efficiency products. (September 2008 update: Robertson Worldwide has achived NEMA Premium Ballast certification for its high-efficiency products as well.)
In the past several years, ballast manufacturers have begun offering high-efficiency electronic ballasts that provide the same light output as a standard electronic ballast but do so more efficiently, reducing lighting power by another 2-5W, typically 3W.
However, this definition of “high efficiency” is informal: Some manufacturers have used it to describe the most efficient products, others to describe all electronic ballasts. Lack of recognition and a slightly higher cost have inhibited market adoption, frustrating manufacturers, which worked together through NEMA to overcome these barriers.
The Consortium for Energy Efficiency (CEE) had worked with NEMA to develop a definition of high-efficiency T8 ballasts—using a metric called ballast efficacy factor (BEF), expressed as ballast factor ÷ input watts x 100—which became adopted as NEMA Standard BL 2-2007 covering electronic ballasts for use with 4-ft. T8 lamps. This standard became the threshold to qualify for designation as a NEMA Premium Ballast.
It is believed this will promote the most efficient ballast options to end-users and utility rebate program generic specs, creating pull-through in the marketplace, as occurred earlier with the NEMA Premium program for electric motors. More than 25 utilities, for example, use CEE minimum performance levels in their incentive programs.
High-efficiency T8 electronic ballasts include instant-start, programmed-start and dimmable models; can be specified as low (<0.86), normal (0.86-1) and high (>1) ballast factor; are available with universal voltage; can be specified for operation of one, two, three or four lamps; and may include value-added features such as anti-striation and anti-arcing. They have no limitations compared to standard electronic ballasts.
High-efficiency ballasts can cost 10-20% more than standard electronic ballasts while producing an additional 5-7% energy savings in typical projects (see Table 1).
In an installation with two-ballasted four-lamp fluorescent fixtures on 10×10 centers (100 sq.ft. area), using high-efficiency ballasts can add about $0.03-$0.06 per sq.ft. to the cost of the project—while reducing annual operating costs by about $0.04 per sq.ft., based on an assumption of savings of $2 per ballast (or $1 per lamp) per year.
NEMA advises this simple language for specification for new light fixtures: “Luminaire shall contain a NEMA Premium electronic ballast (do not substitute).” For retrofit or spot replacement, specify: “Ballast shall be a NEMA Premium electronic ballast (do not substitute).” Then specify the starting method, number of lamps and ballast factor.
While the program currently only covers electronic ballasts operating 4-ft. T8 lamps, the NEMA Premium Ballast program may expand in the future to include T4, T5 and HID ballasts and possibly also LED drivers and power supplies.
For more information about the NEMA Premium Ballast program and to access a list of qualifying ballast models, click here (PDF).