There has been much talk in the news lately of the advantages of compact fluorescent light bulbs (CFLs) versus traditional incandescent lights. They draw far less power, emit the same amount (or more) of light, and last ten times longer. In terms of energy efficiency, it's almost a gimme; your energy bills are lower, and you don't have to replace them nearly as often. California Gov. Arnold Schwarzenegger (it's never gets less surreal the more I type that phrase) has even contemplated banning incandescents in his state and switching everyone over to CFLs.

However, what many of these reports haven't focused on are the environmental impacts of CFLs. It's true that they save a lot of energy, which means we don't have to expend as much fossil fuel to generate the power to light them, but mercury, a toxic substance, is used in its manufacture. From Wikipedia:

Fluorescent lamps (light bulbs) work by passing electricity through mercury vapor, which in turn produces ultraviolet light. The ultraviolet light is then absorbed by a phosphorus coating inside the lamp, causing it to glow, or fluoresce. While the heat generated by fluorescent lamps is much less than its incandescent counterpart, efficiencies are still lost in generating the ultraviolet light and converting this light into visible light. In addition, mercury is detrimental to health, and should the lamp break, exposure to the substance can be hazardous.

As Janet sez: "One compact florescent bulb contains about 4 mg of mercury. [...] Half a gram of mercury (the amount in a traditional thermometer) in a 10-acre lake would warrant a fish advisory. One gram in a 20-acre lake will render all its fish unsafe for consumption for a year."

Now, this doesn't mean that we should abandon CFLs altogether, but that we must be mindful of how we dispose of them. You shouldn't just toss them in the trash, because when they reach landfills or dumps, the glass will shatter and contaminate the area with mercury. One CFL bulb may not do a lot of damage, but if everyone starts using them, all that accumulated mercury could absorb into the soil or the groundwater (or vaporize into the air) and cause both environmental and human health problems.

Wikipedia again:

Mercury damages the central nervous system, endocrine system, kidneys, and other organs, and adversely affects the mouth, gums, and teeth. Exposure over long periods of time or heavy exposure to mercury vapor can result in brain damage and ultimately death. Mercury and its compounds are particularly toxic to fetuses and infants. Women who have been exposed to mercury in pregnancy have sometimes given birth to children with serious birth defects (see Minamata disease).

Some of the toxic effects of mercury are reversible, either through specific therapy or through natural elimination of the metal after exposure has been discontinued. However, heavy or prolonged exposure can do irreversible damage, particularly in fetuses, infants, and young children. Exposure to certain highly toxic compounds of mercury such as dimethylmercury can be fatal within hours or less.

So proper disposal is incredibly important. Here's what the EPA recommends (PDF):

Like paint, batteries, thermostats, and other hazardous household items, CFLs should be disposed of properly. Do not throw CFLs away in your household garbage if better disposal options exist. To find out what to do, first check Earth911.org, where you can find disposal options by using your zip code or by calling 1-877-EARTH911 for local disposal options. Another option is to check directly with your local waste management agency for recycling options and disposal guidelines in your community. Additional information is available at LampRecycle.org. Finally, IKEA stores take back used CFLs, and other retailers are currently exploring take-back programs.

If your local waste management agency offers no other disposal options except your household garbage, place the CFL in a plastic bag and seal it before putting it in the trash. If your waste agency incinerates its garbage, you should search a wider geographic area for proper disposal options. Never send a CFL or other mercury-containing product to an incinerator.

ENERGY STAR qualified CFLs have a two-year warranty. If the bulb fails within the warranty period, return it to your retailer.

Now, that may seem like an awful lot of work, especially if you're a lazy bastard like me. So what do you do? If you want to do the environmentally right thing, and also save money, what's your option?

Enter the LED light bulb.

It's true that LED bulbs are expensive right now (just as CFLs were when they first came on the market), but the following is a good cost analysis between a 60-watt incandescent bulb (what most of us are using now) and a 2-watt LED bulb, both of which put out approximately the same amount of lumens (figures provided by C. Crane):

Life Span (how long will the light bulb last?)
Incan.: 1,000 hours (41 days)
LED: up to 60,000 hours (2500 days, or 6.8 years)

Number of bulbs used over 60,000 hour period
Incan.: 60
LED: 1

Bulb Cost (per 60,000 hours)
Incan.: $40.20 (60 bulbs at 67¢ each)
LED: $34.95

Electricity Usage (kWh of electricity used over 60,000 hours)
Incan.: 3600 kW
LED: 120 kWh

Cost of Electricity (60,000 hours at 10¢ per kWh)
Incan.: $360.00
LED: $12.00

Total Cost (after 60,000 hours)
Incan.: $400.20
LED: $46.95

Money saved by installing one LED Light Bulb: $353.25

This is a no-brainer, folks.

The up-front cost is admittedly more expensive, but you save a mighty pantload of money after that. You're using far less energy, and the bulb lasts 60 times longer (other sources indicate that it may be as much as 100 times longer). Even comparing LEDs to CFLs, you've a six to ten times more efficient light source, and you don't even have to worry about dealing with the mercury in CFL bulbs.

We really need to start pushing LED bulbs more, and pressuring the media to take a bigger look at the technology. Earlier in the year, I reported that Mayor Charles Meeker of my hometown of Raleigh, NC has announced plans to slowly replace incandescent bulbs across the city with LEDs after a pilot project in a downtown parking garage resulted in a 40% reduction of power (via Boing Boing). With Raleigh as a model, we can soon light the entire country in LEDs, and do much to save the environment in the process.