The technology is mature – and beautiful! LED lighting has improved greatly from only a few years ago. The current offerings give a warm light, most are dimmable, they last incredibly long, and the price has come way down. LEDs are now available to replace nearly any bulb type, from the classic “60 Watt light bulb”, to halogen spotlights, floodlights and little halogen or Xenon bulbs. If you remember the Compact Florescent (CFL, the curly bulbs), or the early LEDs, as having a sickly or harsh color, delaying when they turn on, not working with dimmers, or generally being less attractive than the old incandescents – take another look!
Lots of advantages — LED bulbs not only use the least energy to give us light, saving so much money they can pay for themselves in a year or two, but they also run cooler (so they don’t heat your space in the summer, don’t bake the fixtures and wiring). They have no mercury, aren’t fragile, and don’t require disposal as toxic waste -as the CFLs do. They’re simple internally, being low-voltage direct current, so they don’t create radio interference and they don’t blink like fluorescents. We can get creative! LED lighting opens up many possibilities for directional or all-around lighting, a warm room light or a bright task light, and new shapes and possibilities to play with. Without question LEDs are the future.
Types of Lighting:
For indoor use, the earliest type of electric light was the incandescent, which was invented by Thomas Edison and simply heats a wire so hot that it glows. It served us well for many decades, but unfortunately produces a lot more heat than it does light and is easily broken.
Next came the fluorescent, in which a glass tube containing a gas (including mercury) was given a high voltage causing it to glow; then a phosphor coating on the inside of the glass absorbed this light and re-emitted it in the visible range. Fluorescents are more efficient than incandescents and are widely used in office and retail spaces.
In response to the need to conserve energy in households, the Compact Fluorescent Lamp (CFL) was developed by curling the glass tube and making the electronics that are needed to generate the high voltage small enough to fit in the base. This was a heroic bit of engineering, but to this day CFLs are still visibly unpleasant, easily breakable and contain mercury.
Enter the Light Emitting Diode (LED), which actually produces light directly using a tiny chip. It’s a solid-state device with no gases, no glass, and running on low voltage. It also has a phosphor material to make it visibly appealing.
We buy a light bulb to produce light, which is measured in lumens. For example, the light produced by an old 60-watt incandescent is 850 lumens. The energy used by a light bulb is not what we buy it for and therefore want to minimize. That energy is measured in watts – so with LEDs the same 850 lumens might use 9 watts.
We also like to choose either a “warm” color for lighting our homes pleasantly, or a “cooler” color for task lighting. This is called the color temperature, and is described in Kelvin (for reasons a physicist can explain). Bulbs are all labeled with not only their lumens output and the wattage they use, but also the color temperature. 2700K is a warm light, most likely what you’d want for your home and something like 4000K would be closer to daylight for a bright shop light.
LED lights will often work well with dimmers, and will say so on the package. The dimmable ones will work better with certain dimmers. Lutron dimmers are one that work very well with LEDs, and Lutron even offers a version specifically for them that allows the bottom of the dimming range to be adjusted.
Why lighting is especially important:
Switching to LED lighting is low-hanging fruit: they work great, are often more beautiful than any other option, and they’ll save money due to their energy savings and their long life. Here in California we’re getting more and more of our energy from solar, but we typically use lighting when the sun isn’t shining, so reducing our lighting load is especially helpful to help us as we transition quickly away from needing fossil fueled power plants and develop storage for the grid.
Looks like a win all the way around! Remember, it’s about the energy savings and other advantages, not about the light bulb – so don’t wait till your old energy-guzzling light bulbs burn out, upgrade to LEDs right away!
DIMMERS: As referenced in the essay above, some dimmers work very well with LED bulbs. One brand, Lutron, has really focused on LED's and in my experience has been a great choice.
WHERE TO BUY: Locally, LED bulb selection has grown tremendously. Find a wide assortment at Fairfax Lumber, Home Depot and Target.