I shudder every time I flip the light switch in our shed, powering up two 200-watt incandescent light bulbs. Nearly every other light bulb around our home are either energy-saving compact fluorescent light (CFL) or the hot (actually cool) newest product, the light emitting diode (LED).
The first LEDs I replaced were outdoor flood lights that are motion-activated, and now I don't worry as much about "wasting electricity" when a critter walks by or a strong wind blows a branch or unknown object within range of the sensors. Soon, it may be the shed lights.
Most of us reading this newspaper are old enough to relate brightness of light given by a bulb to watts. Over time, it became almost by instinct that we purchased the size bulb needed by its wattage. For reading, I would generally choose a 60-watt bulb, but not anymore. When I learned that I could get the same brightness from a 15-watt CFL, I switched and delighted in saving 45 watts in energy usage. Just recently, I began replacing these with LEDs, but I wait for promotions and sales.
These energy-saving CFL and LED bulbs come with a Lighting Facts panel similar to the Nutrition Facts panel on most packaged grocery items, but instead of listing facts like calories, carbohydrates, protein and ingredients, the panel on bulbs lists brightness (lumens) estimated yearly energy cost, life, light appearance (from warm to cool) and energy used (watts). It took me a while to automatically choose a 24-watt CFL (16- to 20-watt LED) to replace a 100-watt incandescent bulb, or a 15-watt CFL to replace a 60-watt incandescent (6- to 8-watt LED) each providing approximately the same brightness or lumens.
I imagine LEDs will soon replace CFL in many applications, especially as prices drop. LEDs do cost more, but last much longer, and prices are coming down. They do not contain toxic mercury, are more stable, not sensitive to cold temperatures and produce very little heat. For instance, an incandescent bulb that emits 85 BTUs may be compared to a LED's 3.4 BTUs or a CFL's 30 BTUs.
I have always been concerned with breakage and disposal of CFL bulbs that contain 1 to 5 mg of toxic mercury and must not be disposed of with rubbish, but recycled or disposed of with regular fluorescent bulbs. I am especially concerned with CFLs used on table lamps in households with rambunctious youngsters. And the other downside of CFLs is they may (although rarely) smoke or catch fire.