Energy efficient lights, such as “compact fluorescent lights” (CFLs), are all the rage. In fact, many jurisdictions have already banned old-style incandescent light bulbs (ILBs), with others soon to follow. Is this good or bad?
History Thomas Edison, in 1879, perfected the earlier invention of the incandescent light bulb with a graphite-based filament. In 1910, William David Coolidge (1873-1975) devised a tungsten-based filament, which was and still is in widespread use throughout the world. However, in recent years, many “green” advocates and politicians have increasingly promoted compact fluorescent lamps. Some jurisdictions have already mandated their use and the replacement of incandescent bulbs with them. These compact fluorescent lamps are supposed to reduce your home’s electricity use and are good for the environment.
light output Let’s look at ILBs first. They convert about 5% of the energy (electricity) consumed into light, and the other 95% simply turns into heat. By contrast, compact fluorescent lamps emit more than 50% of the energy consumed as light. Therefore, in terms of light output per unit of power consumed, CFLs are far superior to ILBs. So what could be the problem with compact fluorescent lamps?
small letter What is little known to many people is the “fine print” that comes with CFLs. Few people notice it, especially since it is printed on the inside of some packages. However, if you read it, you will find two statements that may encourage you to think again about his decision to “go green” and save electricity:
(i) CFLs are only supposed to be used in lighting fixtures that point them upwards. Often this would mean replacing many of your lamps. Other requirements state that they should not be used with dimmer switches, light sensors, electric timers, and for outdoor use, they need special weather-protected accessories.
(ii) Compact fluorescent lamps contain elemental mercury. Upon breaking, the mercury is released, mainly in the form of mercury vapor, into the surrounding air. Some of it can become small droplets that fall to the floor and embed themselves in carpets, cracks and the like. As liquid mercury slowly volatilizes at room temperature, this elemental mercury constantly produces mercury vapor.
Other costs The basic concern of regulatory agencies is solely the energy consumed per light output. However, electricity is not the only cost incurred by the user of the CFLs. For starters, CFLs are significantly more expensive than ILBs. To appear cost-competitive, several jurisdictions addicted to “green energy” are subsidizing their purchase with taxpayer money—in other words, their money. Second, the light output of CFLs decreases over time. Third, CFLs take about a minute to reach full light output. CFLs also fail more easily with (relatively) frequent switching on/off. More importantly, they also have potential health and cleaning costs associated with them, as described below.
Effects on health and cleanliness Compact fluorescent lamps contain mercury. It is well known that prolonged exposure to mercury vapor causes serious effects in humans, such as tremors, etc. So the question is: how safe are compact fluorescent lamps? As long as they don’t suddenly break or burn out due to the failure of the built-in ballasts, there shouldn’t be any health concerns with their use. However, upon breaking, the mercury is likely to be released into the surrounding area with its potential long-term hazards. That is also the reason why these things are supposed to be disposed of in so-called hazardous materials landfills where most of them are crushed and the mercury is volatilized from there. Fortunately, the US Environmental Protection Agency provides detailed instructions for cleaning up mercury spills from broken CFLs. This is available on the EPA website [1].
In summary So, overall, for many situations, the benefits of CFLs are less and their actual and potential drawbacks are greater. But remember, it’s for the good of the environment, at least the EPA thinks so.