Q: Besides their goofy shape, what makes compact fluorescent light bulbs different from regular ones? Why are they supposedly so good for the environment?
A: With Earth Week crawling ever closer, your question couldn't be timelier. Essentially, CFL bulbs are simply more efficient, because they use less energy to illuminate the same amount as regular bulbs.
This difference results from the different ways the two kinds of bulbs work. The old kind, technically called incandescent light bulbs, work by passing electricity through a thin piece of metal called the filament. The electricity makes the filament heat up, and soon enough it becomes white-hot, bright enough to illuminate the bulb's surroundings.
All this happens inside the familiar glass bulb, which keeps a vacuum (no air) around the filament. This serves to prevent oxygen in the air outside the bulb from getting to and oxidizing (burning up) that super-hot filament.
CFL bulbs, however, are just like regular fluorescent bulbs, only smaller and more compact. Perhaps most familiar to us as the long tube lamps found in office buildings and lecture halls, fluorescent bulbs produce light totally differently.
Instead of heating up a piece of metal until it shines, fluorescent bulbs use electricity to excite mercury vapor, which emits invisible ultraviolet light. A coating of phosphor on the inside of the bulb then absorbs this light and emits the bright light we see. This process is called fluorescence. Since the light we see comes from the phosphor coating, the more surface area the bulbs have, the brighter they become.
Although it may seem odd that the flickering, soulless lights of government buildings may be the future of household lighting, it's really just putting an entirely different kind of light to good use.
Fluorescence gives the neon lights of the big city their striking glow and doesn't create nearly as much heat as their incandescent equivalents. CFLs are merely these efficient fluorescent tubes folded and spiraled up (to keep surface area, and thus efficiency, high) and made compatible with regular incandescent sockets.
This efficiency makes them the greener alternative. When you screw in a CFL where you once had an incandescent bulb you use between one third and one fifth the power for the same amount of brightness and illumination, according to General Electric.
Plus, according to the National Energy Foundation, your new CFL bulb will last between eight and 15 times as long as its incandescent predecessor. So, combining the longer lifespan with the difference in energy use, Energy Star calculates you'd save around $30 per CFL bulb you use.
Of course, nothing's perfect. For instance, CFL bulbs are more expensive than their incandescent counterparts. Even though the increased efficiency would more than make up for the difference in cost, many are hesitant to make this initial investment - it's hard to value long-term savings over the short-term cost, especially with the current economy.
Also, the mercury in CFLs makes getting rid of them a bit of an issue. Used or broken bulbs have to be disposed of very carefully at specific recycling locations, and few people do so. And yet, in places powered by coal, CFLs still decrease mercury emissions over incandescent bulbs, since it would have taken more coal (which releases mercury) to power the less-efficient bulbs.
So, funny-looking though they may be, CFL bulbs really are the most efficient, cleanest and most economical alternative. Their shape and higher price may take some getting used to, but by almost any measure it's a change you'd be wise to make.
So, funny looking though they may be, CFL bulbs really are the efficient, cleanest and most economical alternative. Their shape and higher price may take some getting used to, but by almost any measure it's a change you'd be wise to make.
