Letters
Dedicated fixtures
Readers of our article "Dedicated CFL Fixtures Bring Savings Home ", in the last newsletter (1/95) have asked for more elaboration on how we see the respective roles of screw-based versus pin-based compact fluorescent lamps (CFLs) in the residential market. The following is a continuation of the discussion initiated in the original article.Reply: One of the "curses" of energy efficiency is that it often means increased consumer choice; thus more effort is required in selecting the best technology to do the job at hand. Lighting is an especially impressive example of this phenomenon. Where once a simple bare A-Lamp and switch were used for virtually all applications, today many thousands of combinations of lamps, ballasts, controls, and fixtures are available to consumers. An emerging area of focus is the increasing number of options for applying CFLs.
There are many places in existing homes where a screw-based CFL would be appropriate. Most lighting energy is presently used in existing screw-based fixtures. We also see an emerging niche for hard-wired dedicated fixtures in the new construction and renovation marketplaces and where consumers are purchasing new portable luminaires for existing homes. In the US alone there is a $4 billion/year residential fixture market (165 million fixtures per year). This has become an exciting new target for utility and government energy efficiency programs.
Competing with power plants
To be truly competitive with new power plant construction, conversions to efficient lighting must offer equivalent service levels and be maintained for up to 30 years. And the life-cycle cost of the efficient lighting systems must be equal to or less than the value of the power they save. There will normally be a price premium for hard-wired CFL fixtures, as compared with the standard screw-based version. However, since replacement lamps are less expensive (because the ballast does not need to be repurchased each time), the total lifetime cost could actually be lower than it would be if a series of integral lamps were to be purchased.
Even where straight economics does not prevail, if the quality of the light is better the consumer may still prefer an optimized fixture. After all, energy savings alone are not what motivates many households to spend small fortunes on (pin-based) halogen fixtures. The nearly universal choice of pin-based CFL fixtures in the commercial sector must also be recognized.
The problem is not simply one of pin- versus screw-based systems. Fixture performance must be addressed as a totality. We have measured luminaire efficciencies as poor as 19 lumens/watt for common Western-made lamp-fixture systems that are promoted as achieving 70 lumens/watt. Both lamp and fixture manufacturers can take steps to ensure that this kind of situation is avoided in the future.
Variation in consumer satisfaction
We have noted a wide variation in consumer satisfaction in connection with utility CFL campaigns. In the best cases, consumers claim to be very satisfied and promise to buy replacement CFLs in the future. In other cases the situation is not so good. Market survey statistics have convinced some US utilities to assume only 2/3 of the theoretical savings-this is a blow to their efforts to justify the cost-effectiveness of DSM programs for screw-based CFLs.
In a recent comparison of four US rebate programs, up to 15% of the consumers chose not to install the CFL, and up to 9% removed their lamps early because they were dissatisfied with their performance. The Los Angeles Department of Water and Power found that 45% of all CFLs had been removed within two years! Unfortunately, in many cases it is not known why these consumer-acceptance problems occur-thus, better surveys are needed. In a recent report from Sweden's Uppsala Energy, for example, 80% of the contacted consumers were reported to be satisifed with their CFLs, but only 60% replaced burned out ones with another CFL.
European and US differences
European and US utilities are at "different stages of life" when it comes to residential lighting programs. After about ten years of intense enthusiasm about screw-based CFLs, many major US utilities are shifting their marketing strategy from screw-in to dedicated CFL programs. This marketing strategy is enabling these utilities to achieve more reliable and durable energy savings (for the regulators) and better light quality (for the customers). We are also aware of various stakeholders in the European energy efficiency arena-France, UK, Sweden, Netherlands, Poland-that are now considering strategies for promoting CFL fixtures.
On the other hand, European consumers have had the benefit of more advanced (e.g. smaller) CFLs far longer than have consumers elsewhere in the world, which could partly explain why European customers are reported to be more satisfied with their lamps. As integral CFLs get smaller and smaller, they will compete more and more effectively with pin-based lamps. Continued industry development and improvements of the screw-in lamps are quite welcome!
Consumers want flexibility
We must also keep in mind that some consumers will simply want the flexibility of being able to choose between incandescent and fluorescent light sources in a given fixture. That's one reason why utility and other voluntary incentive approaches are better than standards.
Applications, not technologies
This kind of discussion is not limited to CFLs. The whole energy efficiency movement is learning (sometimes the hard way) that efficient technologies often do not work as expected and that savings do not persist over the "engineering lifetime" of the product. The cutting edge of energy efficiency is no longer technology; it's applications!
To sum up, we believe that screw-in and dedicated fixtures each have a place in the world. In both cases, it is necessary to recognize and remedy the performance problems with many existing fixture-lamp combinations. Utilities and others promoting energy-efficient lighting need to become more aware of the options and be more attentive to the implications of their choices.
For more elaboration on the issues and new implementation strategies, see our article in LD+A (Lighting Design and Application) March 1995), entitled "Dedicated CFL Fixtures for Residential Lighting".
Evan Mills