July, 2008

Energy Efficient Lights

These lights save energy and money, which makes them a very green choice.

By Steve Easley

I’ve been asked often recently about energy codes that now require more energy efficient lighting. I have a few thoughts about lighting technologies for homes.

Lighting in general accounts for 8% to 10% of a home’s energy bills, so switching to the newer technologies can save both energy and money.

Many of the new lighting products available pay for themselves in a very short time, making them cost-effective investments. Since energy-efficient lights are also longer-lasting, they are considered greener products than standard incandescent light bulbs. (Every KWH of electricity we use results in a pound of greenhouse gases being released into the atmosphere from our power plants.)

In the U.S., Americans go through about 1 billion standard light bulbs a year. It takes a lot of energy to manufacture those light bulbs, because making glass requires a lot of heat, not to mention the energy needs to transport those bulbs to and from stores, to our homes, and to the landfill when they burn out. These bulbs rarely get recycled.

The technology for incandescent lights has been around since the late 1870s and hasn’t evolved much since. About 90% to 95% of all the energy that is used to power an incandescent bulb is converted to heat as opposed to light. Because of its low efficiency, an incandescent bulb is a significant contributor to global climate change. In fact, many countries have a timetable to ban the sale and use of these bulbs.

If every American home replaced just one light bulb with an Energy Star-qualified bulb, we would save enough energy about the same size as a standard light bulb; use about one-fourth the energy of an incandescent, and last eight to 10 times as long. The downside is that they contain mercury, which is not good for the environment when the bulbs are disposed of improperly. (Newer models have less mercury, however. An old-style thermometer has about 100 times more mercury than a new compact fluorescent.)

Also, many CFLs do not work with traditional dimmers, so if you want a dimmable light, the bulb has to be designed for use with dimmers.

When buying lights, always look for the Energy Star label.

LED Lights

LED lights are sometimes called solidstate lighting or SSLs. These are amazing because they are very energy efficient and long-lasting, and contain no mercury, which makes them a very green product.

LEDs are the most efficient of the lights commonly available. I’ve been particularly impressed with one product made by LED Lighting Fixtures Inc., also known as CREE LLS Lighting Solutions.

The company won the grand prize for their can/down light insert in the 2007 Lighting for Tomorrow solid-state lighting competition, organized by the American Lighting Association, the U.S. Department of Energy (represented by Pacific Northwest National Laboratory), and the Consortium of Energy Efficiency. The company also won the United States Green Building Council’s (USGBC) product of the year.

LEDs are also dimmable using standard dimmers, and can have outstanding color rendition. Under normal use, some models can last 20 years or 50,000 hours! (Can you imagine installing a light when your child is born and not replacing it until they go to college!)

Another advantage to LEDs is that they are very easy to retrofit into existing can lights; they generate very little heat, and they are also great for hard-to-reach places like high ceilings.

STEVE EASLEY is president of Steve Easley & Associates, which consults and trains on building science issues. His seminar topics include reducing call backs, high-performance building envelopes, and cost-effective strategies for green building. For more information, visit www.codecollegenetwork.com.