More expensive lightbulbs save you money in long run

This weekend, spend a couple of hours walking through a local building-supply or hardware store, and check out all the inexpensive energy-saving products on the shelves, such as the efficient light bulbs.

You may be surprised to find that the prices of energy-efficient lights have dropped. Long-lasting compact fluorescent bulbs come in a variety of sizes and shapes to fit just about any lighting fixture, and at prices that make them inexpensive over their lifetime. You’ll be amazed at some of the lighting products in the stores.

Compact fluorescents are four times more efficient in producing light for a given amount of energy than are incandescent bulbs. They also produce less heat than the incandescents and last up to 10 times longer.

You’re thinking, “Sure, these bulbs sound nice, but lighting is such a small part of my monthly energy costs. Why should I spend more for these bulbs if I really won’t save that much?”

Yes, lighting accounts for only about 10 percent of the energy you use in your house. If last month’s utility bill was $100, about $10 of that covered your home’s lighting. But even the smallest areas of savings still add up.

Consider a study researchers at the Florida Solar Energy Center conducted several years ago on a house in Miami that had extensive use of interior lighting.

With 40 lamps or bulbs in the home — almost double the number in the typical home — the owners also had relatively high utility bills.

The researchers put data loggers on all of the home’s appliances and on each lighting fixture to determine energy use. In this case, the home’s occupants liked a lot of lighting, and research showed that it accounted for nearly 23 percent of their total annual energy consumption.

The biggest user of electricity for lighting was for outdoor light fixtures, followed by the kitchen, garage and study. Just these areas accounted for 80 percent of the home’s total lighting use.

The researchers substituted 27 different types of compact fluorescent bulbs and other efficient lighting sources in the home in place of incandescents, and installed motion sensor controls for the exterior lighting, at a total cost of $400.

Monitoring the home for six months after these changes showed a reduction in household lighting energy use of 61 percent. The researchers also estimated the savings more conservatively by multiplying the per-fixture light usage in hours by the changed lamp wattage, and calculated a 47 percent savings this way. They did not include the savings from the outdoor lighting system improvements.

Even though the purpose of this study was to achieve the maximum lighting energy savings possible instead of just seeking the most economic savings levels, the savings of between 47 percent and 61 percent have an annual value of $150 to $200 at current utility rates.

The payback for the improvements would be just two to three years (not counting the extended lifetime of the more efficient lights for the projected lives of the incandescent bulbs or the lower cooling bills from the reduced heat output of the better lamps).

If just saving money had been the goal of the study, the researchers concluded that concentrating on the outdoor and kitchen lighting and other heavily used fixtures would have given a 30 percent savings for an investment of only $170.