What about the quality of light? Is it not the case that energy efficient lighting produces poorer quality lighting than traditional bulbs, and that the bulbs flicker?
This is not the case. Good quality energy efficient lights produce the same light output as incandescent lighting. Flickering used to be a problem with traditional fluorescent tubes, but that is not the case with the current generation of CFLs. In addition, Tungsten Halogen bulbs look and function the same as incandescent bulbs.
I have found that the quality measurements being used by government agencies have failed to include measurement of the spectral uniformity. Incandescent lights have a spectral continuity somewhat like that of natural sunlight. CFLs, however, have a spectral continuity similar to conventional fluorescent lights. A lot of the effects of fluorescent lights in the past have been incorrectly attributed to flicker. Instead, the problem in many cases is due to the fact that the spectrum has two or three distinct emission bands.
The human eye does not focus all wavelengths of light at the same time. There is much science of lens design to correct optical devices (cameras, telescopes, microscopes, etc) in this regard. The effect in the human eye is not significant enough for people to notice because the brain does things to compensate. This compensation works best with natural sunlight that has a fairly uniform spectrum.
When viewing black on white text under a single wavelength light, the edges of the letters will be sharp and crisp because the eye can focus exactly as needed. When the light is a broad spectrum like sunlight or incandescent, that focus averages to the center of most of the light, generally slightly to the green side of the yellow wavelengths. The edges will effectively be soft in the blue and far red portions of the spectrum. But this doesn't affect the ability to read the text and is generally not seen by most people. People using corrective lenses could see a greater effect because these lens make it a bit worse.
Under most fluorescent and most LED lighting, the spectrum has two or three distinct bands or peaks of emission. The human eye has more difficulty focusing on this kind of light. In particular, the focus tends to wander or shift back and forth between the red peak and the green peak. The brain continues to hide this. However, it creates a level of stress in the brain as well as in the eye muscles.
I have personally found that I cannot read a newspaper (black text on white) under fluorescent light for more than about 15 minutes before stress becomes noticeable. By 25 to 40 minutes it can become a genuine headache. This effect happens from both fluorescent tubes as well as CFLs. Any kind of task involving this kind of light I generally find to be time limiting due to the headaches that can happen. The tasks that can be affected include non-reading work in the kitchen and shop areas. I am affected by this more than the average person. But I believe a significant portion (15% estimated) of the population could be severely affected. Most would not understand why.
I have also found that some halogen lights (a form of incandescent) have this effect. It appears the effect may be due to prismatic effects of the reflectors, lenses, or dichroic coatings, that many of these bulbs and fixtures include. When encased in diffusing fixtures, the effect is diminished.
Count me in as one of the stockpilers of incandescent bulbs.
What about price?
Will the public end up spending more on lighting?
They will actually be spending less. While energy-efficient alternatives are more expensive to buy initially, they save money in the long run. Good quality CFL bulbs can last ten times as long as ordinary incandescent tungsten filament bulbs. In addition, they use just one fifth of the electricity used to power an incandescent bulb.
Unfortunately, a great volume of CFL stock available at discount retailers is not the "good quality" that would make a CFL last ten times as long as ordinary incandescent bulbs. I have incandescent bulbs running well beyond 8 years. Few ever burn out in less than 3 years and almost all of them are the low wattage bulbs, particularly 4 or 7 watt bulbs (C7 socket, generally used as nightlights). The lower wattage bulbs have thinner and longer filaments, and thus are weaker. Bulbs intended for the 230 volt markets such as Ireland will be inherintly weaker than the same wattage bulbs for the 120 volt markets.
What about medical conditions? Is it true that some energy efficient lighting has negative effects on people suffering from conditions such as epilepsy, lupus or migraine?
Again, this is an area covered by this consultation process, to establish if this is the case, and if any special measures are needed to cater for this. However, as per above, Tungsten Halogen Bulbs would seem to provide the answer if this is the case.
Halogen bulbs can be used, but must be carefully selected and properly installed to eliminate the spectral effects, where this issue is what affects the people involved.
The hum of some fluorescent lights can also affect people. These people could in turn be affected by the hum of the transformer stepping line voltage down to the typical 12 volts used by halogen lights. Locating the transformer at some distance can resolve this issue. This rules out integrated halogen units that work directly from line voltage and include a small step down transformer.
Is it true that CFL bulbs do not work with dimmer switches?
The Department understands that there is an issue in relation to dimming in the case of some CFL\u2019s. Tungsten Halogen bulbs are fully dimmable.
This is misleading. While it is true you get a smoothly reduced light when dimming a halogen light, the lower temperature involved can disrupt the halogen vapor cycling that extends the life of the high temperature filament. The problem with dimming a halogen light is it can severely reduce the life of the bulb.
Additionally, many dimmers can cause severe heating of the step down transformers used to reduce line voltage to the halogen operating voltage. Dimming of halogen lights that have integrated transformers (intended to be used in line voltage sockets) could, in addition to a shortened life, be a fire hazard.
