The little red light has grown up, and a new
generation is on the horizon.
That tiny red bulb you’ve seen for years on transformers,
camcorders and electronic devices — the LED — is about to revolutionize the
way we light our homes and businesses.
That little red light is no longer just red. Or little.
LEDs, or light-emitting diodes, now come in every color in the rainbow — and
some that are not even visible to the human eye. More importantly, LEDs have
grown brighter, they are proving to last a long time — a very long time —
and they are stingy in how they use electricity.
That last quality, the efficiency of the LED, happens to
be extremely important right now. Although it wasn’t particularly noticed at
the time, federal legislation in 2007 set new and much tighter efficiency
standards for light bulbs.
“This legislation is going to essentially begin to remove
incandescent bulbs from the market,” explains Catherine Powers, vice
president of forecasting & member services for Old Dominion Electric
Cooperative (ODEC). “The bulbs we’ve known for a hundred years are going to
start disappearing from store shelves.”
These new rules, which will begin phasing in next year,
don’t explicitly ban any particular type of bulbs. However, the very nature
of incandescent light bulbs means it will be almost impossible for
manufacturers to make them efficient enough to meet the new standards.
Most experts believe Americans will have to start turning
to more efficient alternatives — compact fluorescent lamps (CFLs) and LEDs.
CFLs, the compact fluorescent bulbs that already crowd store shelves, will
generally meet the new standards and will last several times longer than
traditional bulbs, but they are not without a few issues of their own. Many
CFLs emit a light that is bluer, or “colder,” than people are used to, and
the safe disposal of these bulbs has raised some concerns. Most CFLs contain
trace amounts of mercury.
LEDs, on the other hand, are not only safe to discard,
they last so long that throwing them away simply does not occur that often.
And they are efficient, far more efficient than incandescent bulbs. Many are
significantly more efficient than CFL bulbs.
“It’s really pretty simple,” reports Erin Puryear, ODEC’s
manager of energy innovation planning. “LEDs are extremely energy efficient,
extremely long lasting, and extremely versatile. We think they’ll play a
huge role in how we light homes and businesses in the future, and how we
Traditional incandescent lights, the kind we’ve used for
more than a century, force electricity through a small wire, or filament.
The filament gets white hot and emits light — and a lot of heat. In fact,
most of the electricity used by an incandescent bulb is actually given off
The LED is different. In reality it is a tiny bit of a
semiconductor material — the kind of material in computer chips, mixed with
specific chemicals. Just a little electricity causes the LED to glow in a
process called electroluminescence. Since little heat is produced, LEDs
produce a lot more light for each unit of electricity — they are much more
LEDs have enormous potential, according to the U.S.
Department of Energy. The DOE projects that the use of LED lighting alone in
2030 will lower U.S. energy demand by 194 billion kilowatt-hours, or by the
total annual power output of more than 28 generating stations the size of
ODEC’s 850-megawatt Clover Power Station. The energy cost savings in that
year alone will be $15 billion, DOE says.
How can the tiny little LED account for such gigantic
savings? “The technology ...” responds Robert Kirkland, utility relations
manager at General Electric. “We think the technology is fantastic.”
Kirkland speaks with a bit of pride because the first visible-light LED was
created by a GE engineer in 1962.
That first LED was red, the ubiquitous glowing red dot
that began to appear on electronic devices more than 30 years ago to
indicate their status — and even popped up in a grid-like arrangement as the
numeric display on early electronic calculators. Eventually, other colors
were developed, and LEDs became brighter. In the 1990s the technology began
an explosive growth that still continues. DOE says research firms and
manufacturers announce a major new generation of LED technologies almost
every six months, new technologies that make LEDs even more powerful, and
James Broderick, lighting program manager for the DOE
Building Technologies Program, recalls, “Just five years ago, the best
white-light LED was running 20 lumens per watt; now it’s 100 per watt. The
efficiency has increased enormously, and we expect that to continue.” The
lumen is a measure of light. A 100-watt incandescent bulb is rated at only
17.5 lumens per watt, or five times less efficient.
These new semiconductor lights are not only more
efficient than incandescent and fluorescent bulbs, they are also much less
subject to being damaged by vibration or dropping, and they last a very long
time. While most major lighting manufacturers currently expect their LED
bulbs to last at least 25,000 hours — or about 25 times as long as
traditional incandescent bulbs — some project these new bulbs may last
50,000 hours or more. In addition, while typical incandescent and CFL bulbs
dim significantly as they grow older, LEDs do not.
Experts are calling LEDs a “generational” bulb.
Theoretically, if you buy a bulb for your new child’s room, it will still be
there and working when that child graduates from college. It can be said to
last an entire generation.
Yet LEDs are not a perfect solution for all lighting
needs. Kirkland says, “The LED is a great solution, but it’s not the only
solution. It doesn’t work in all applications.” He notes that efficient
halogen bulbs, or CFLs may be better in certain specific uses.
An LED is directional — it produces light that goes in
one direction. Traditional bulbs emit light in all directions. Most of the
LED bulbs that first appeared on store shelves looked like traditional
bulbs, but really threw light only in one direction, like a floodlight.
However, manufacturers are now producing bulbs that use many LEDs pointing
in many directions — along with reflectors and diffusers — to match the
all-around lighting of conventional incandescent bulbs.
And LEDs can’t use the kind of alternating current in
most homes and businesses. LED bulbs that fit regular bulb sockets must
contain small electronic devices to convert the electricity. Such devices
are not a technical problem, but they do raise the cost of these bulbs.
Lisa McLeer, GE Lighting’s marketing manager, reports her
company began to manufacture and sell its first omni-directional LED bulb
late last year, a 40-watt bulb that uses only 9 watts — but costs $50. Other
LED bulbs are now selling for from $19 to $90 each.
While that cost seems high, when you sit down and
actually compare different bulbs — how long they last and how much energy
they use — LEDs are far less expensive than incandescent and even CFL bulbs.
For example, you would have to buy from 20 to 60 traditional incandescent
bulbs — or up to 6 CFLs — to have them last as long a one LED bulb.
But the real savings with LED bulbs lies in their energy
efficiency. A 40-watt traditional bulb burning 4 hours a day would use
almost 60 kwh in a year. At about 12 cents per kwh — an average figure for
mid-Atlantic electric customers — that would be about $7 a year. An LED bulb
that gives off the same light would use 9 watts, just over 13 kwh or $1.60 a
year — a $5 annual savings. The savings would pay for the higher cost of the
LED bulb in less than 10 years, yet the bulb would last 30 years. For
consumers, LEDs should be a slam dunk.
However, ODEC’s Powers explains the acceptance of LED
bulbs by consumers will take work. “LEDs offer a huge potential to save
energy and money, but they also present a big customer education challenge.”
She notes that LEDs save energy, last decades, and are highly shock
resistant, “but this is a whole new technology for us and for our
Powers notes that CFLs presented the same kind of
challenge a decade ago as customers learned what to look for in a new
technology, and how to best use it. She urges co-op customers to learn about
the new LED lights in the same way, to look for bulbs by major
manufacturers, and those with the ENERGY STAR rating.
“We’re going to continue to work with manufacturers to
keep up with this growing technology, and to share what we learn with
customers,” Powers says. She also indicates cooperatives may offer customer
incentives to keep costs down.
“LEDs offer an exciting technology, and are part of a
whole new way of looking at lighting. I expect we will be discovering new
LED capabilities and benefits for years to come.”