A whole new light
By Nancy S. Grant from July 2014 Issue
Credit: Tim Webb
Hi-tech bulbs get better and better
The first two LED light sources I bought years ago still work—and yet they're not quite right. My clip-on LED book light is good enough for reading a few pages in a darkened room, but pretty soon the glare makes me squint. And although the little LED flashlight is bright enough to find cat toys under the bed, I wouldn't want to use it for much else. To my eyes, those old LEDs look like some kind of weird moonlight instead of the sunshiny, candlelight gleam of the incandescent bulbs I've always known.
Of course it's not fair to prejudge today's LED products based on old battery-powered devices. The newest LED lights for use in light fixtures in homes and outdoors are supposed to be a big improvement. They cost more, but they use only a tiny bit of electricity from the power grid, a fraction of what incandescents use, and they last a really long time. But will I like them?
I went shopping to find out.
What is an LED light?
LED stands for Light Emitting Diode, a fancy way of saying a tiny solid-state device that glows when electricity passes through it. You're most familiar with them as the numbers on digital clocks. LED lights offer many advantages—they use very little electricity, they don't get hot, they come on instantly, and they can be dimmed. A single LED, however, produces only a small amount of light in one direction. To make them more useful and attractive, they are often grouped into arrays, with reflectors or diffusers added.
Joe Rey-Barreau, lighting design professor at the University of Kentucky, says, "In the last four years, LED has become a mainstream lighting technology not only because the cost has come down, but also because the performance has improved. And that's mostly about the color. The quality of the light, the color of it, is equal to or better than incandescent."
But today's LEDs involve a lot more than getting the color of the light right. A single LED is only about a sixteenth of an inch square, smaller than a pencil eraser. Rey-Barreau says, "You have to use multiple LEDs to create light that is usable."
I was looking for a light to use in a brass table lamp in my living room. I wanted a familiar size, shape, pattern of light spread, and the same kind of base as the old bulb.
Making a product like that has been a big challenge for LED manufacturers. Different companies have solved the problem in different ways, using unique arrays of LEDs in the upper section (the "bulb" area) to create a product that looks and performs a lot like the old incandescents. I bought a high-tech LED that uses only 18 watts of electricity—but should give off the same amount of light as my old 100-watt bulb.
If I wanted to buy a new lamp, I could try something trendy. On their own, individual LEDs don't need a socket or base—they can be used anywhere, connected directly to the electricity supply by nothing more complicated than a very thin wire.
Rey-Barreau says, "LEDs are not really a light bulb in the traditional sense. Designers can create innovative light fixtures where the LED is integrated into the shape of the design." Their tiny size and cool operating temperature offer opportunities to completely rethink lighting. Instead of being grouped tightly together, LEDs can be scattered around and used anywhere in a fixture to create an artistic effect.
Lighting the outdoors
I only turn the living room lamp on for a few hours each evening, so I probably won't notice much difference in my monthly electric bill by changing just one bulb. But the energy savings are obvious for an outdoor light that's on every night from sunset to sunrise.
Mike Benson, director of Sales and Marketing at United Utility Supply Cooperative, which provides devices and services to more than 200 electric cooperatives in 17 states, says, "We're selling outdoor LED lights to local co-ops to install at their members' sites on the basis of their low maintenance and great energy savings to operate. Compared to the old sodium lights, a 60-watt LED takes half the energy, but the light is just as strong and of a pleasing color. LEDs can last 20 years or longer. That means fewer service runs by the local co-op—and that saves everybody time and money."
In Kentucky, all 24 local distribution electric cooperatives have installed at least one LED outdoor light for observation and evaluation. As time and service crews are available, many have already begun replacing their members' old outdoor lighting with the new LED style.
John Wheeler, vice president of Engineering at Pennyrile Electric co-op in Hopkinsville, says, "We have about 13,000 outdoor area lights in our system for yards and around barns. We're replacing about 450 lights each month. We've had no complaints—people like the color of the light better."
Good quality light, long life, and fewer maintenance runs make LEDs an attractive choice for public roadway lighting, too. Pennyrile Electric is planning several replacement projects with cities in their service territory eager to save money and time by installing energy-efficient LED lights on their streets.
Energy journalist NANCY GRANT is a member of the Cooperative Communicators Association and the American Society of Journalists and Authors.