2012 update - from CFLs to LED

In the last few years LED technology has developed dramatically and has become a good alternative to compact fluorescent lighting discussed in these pages. Their prices have come down, the quality of light has improved significantly and they are now available in several different models and sockets for almost all kinds of fixtures. Compared to CFL's LED has many advantages: they are even more energy efficient, they last even longer, they don't break as easily and they don't contain toxic mercury. For these reasons we now recommend trying to see if you can use LED technology and only use CFLs if LEDs don't do the job properly.

The following information is still valid for CFLs and can be helpful if you a) can't find a suitable LED b) need to dispose an old CFL and want to know how and where you can do that.

Energy efficient lighting

Using energy efficient lighting is in fact quite simple and these two pages will give you all the information you really need to use energy efficient lighting effectively. We will discuss how to choose the energy efficient light bulbs, how to handle them, where to use them and where and how to dispose them. Even though energy efficient light bulbs can seem expensive at first, they will in fact save you money when used properly. First we will discuss using ordinary energy efficient "compact fluorescent light bulbs" for general lighting and later take a look at some other energy efficient lighting solutions for reading and working.

Here is a quick comparison:

Pros - Energy efficient compact florescent light bulbs:
+ save energy (using only about 25-35% electricity)
+ last longer (about 10 times longer)
+ do not need to be replaced as often
+ generate less heat
+ in the long run save money

Cons:
- are more fragile (especially when hot)
- the quality of light is not always quite as good (still ok for general lighting)
- the price of a light bulb is higher, but is more than compensated with the longer life and the energy saved
- contain small amounts of mercury and used CFL bulbs therefore need to be disposed of properly

Save energy - save money

The price of a cheap energy efficient light bulb is usually between five to ten times higher than an ordinary incandescent light bulb. If you use them correctly they will last about eight to ten times longer making the price the same - if not cheaper. The power consumption on the other hand is only about 25-35% compared to standard incandescent light bulbs. As the price of the bulb is practically the same, all the energy saved will save you money. Even if you bought a really expensive model, you would still end up saving money.

Let's do the math...

A compact fluorescent light bulb lasts about 10,000 hours. Let's say you replace one standard 60W light bulb with a 15W energy efficient light bulb. This way you will save 0.045 kWh's of electricity per hour (60W-15W = 45W = 0.045kW). So in the life time of the energy efficient light bulb you will save 450 kWh's of energy. If you pay $0.083 per KWH (average) that makes a total saving of $37! Not bad for replacing one light bulb.

Of course to get that kind of a saving the energy efficient light bulb must really last for the expected 10,000 hours. But even if you only got 5,000 hours, that would still save you enough money to buy a new one. Below I will give some guidelines on how to use and handle energy efficient light bulbs so that they will last as long as possible.

• If every household in the U.S. replaced one light bulb with an ENERGY STAR qualified compact fluorescent light bulb (CFL), it would prevent enough pollution to equal removing one million cars from the road. Source: http://www.energystar.gov

Where and when to use energy efficient lighting

Even the cheapest compact fluorescent light bulbs are good for general lighting. With the cheap models the quality of the light is not always quite as good as with ordinary light bulbs, but this is still just fine for general purpose lighting. For reading and other tasks where you require good lighting conditions I recommend a little more expensive energy saving alternatives which will be discussed later.

Compact fluorescent light bulbs are more fragile than ordinary ones. Especially when hot they can break quite easily. Therefore it is not a good idea to use them on lamps which you will move or you might accidentally hit. On the other hand, the longer life makes them ideal for places where the lamp is difficult to reach.

Switching the light on and of will make the bulb wear out faster than having it on continuously. Therefore I don't recommended using compact fluorescent light bulbs when they will only be used for short periods at a time. As the lights are not used for long, the energy savings are not that big either, so you can just as well use ordinary light bulbs. In addition, compact fluorescent light bulbs are more efficient when they operate for several hours at a time (2 hours or more).

This article from Treehugger.com addresses the issue of when to turn lights off and when it is better to leave them on. Here's the short version:

"The rule of thumb for optimizing the in-use versus turn-on power is:

• Standard incandescent: turn off even if you leave the room for just seconds.
• Compact fluorescent: turn off if you leave the room for 3 minutes.
• Standard fluorescent: turn off if you leave the room for 15 minutes."

Source: http://www.treehugger.com/files/2005/06/user_tips_for_c.php

Most energy efficient lights bulbs should only be used in moderate temperatures indoors. If you wish to use energy efficient lighting outdoors, make sure you buy light bulbs that have been made for outdoor use. Similarly, most compact fluorescent bulbs are not dimmable - if you are using a fixture with a dimmer, make sure you buy one that has been designed for that.

Energy efficient light bulbs are really handy if you want to get more light from your lamp, but have reached the maximum wattage allowed. Say you have a fixture that allows a 60W max light bulb. Instead of using a regular 60W incandescent lamp, try using a 20W or 23W compact fluorescent. You will be nowhere near the 60W maximum, but still get significantly more light than with the 60W incandescent.

Handling compact fluorescent light bulbs

You should avoid contact with the tubes and always handle the bulb from the base only. If you can't avoid touching the tube, use soft gloves. Using gloves is not as critical as with halogen lamps where oils from your hands can dramatically reduce the life of the bulb (something to remember when changing the headlights of your car for example). With some fixtures it is difficult to avoid touching the tube when replacing the bulb, so I usually use gloves just in case. Even if you use gloves, you should still avoid contact with the tube because it is really quite fragile.

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