In this installment of 10 Questions for . . . , Associate Editor Kimberly Janeway speaks with Ed Hammer about his 1975 invention, the compact fluorescent lightbulb, and why it took so long for this innovation to reach the marketplace. Hammer (shown with the first CFL) has worked in the lighting industry for 50 years and holds more than 40 patents.
How do you feel about being called the father of the CFL? And does Edison inspire or haunt you?
"Father of the CFL" is a nice title—I'm fine with that. I wasn't haunted by Edison. I wanted to make the world a better place; it's still my goal.
What led to your invention?
I was a senior physicist at GE Lighting in Cleveland and was working in fluorescent lighting in 1973, when we had the energy crisis in this country. As a result, we designed a bulb commonly called the F-40 Watt-Miser, the first energy-efficient linear fluorescent lamp. That said, I thought we might as well get a replacement for the 100-watt incandescent lamp. That type of lighting is very, very inefficient.
What did you envision as a replacement for incandescent bulbs?
I thought if we could get a fluorescent replacement, we'd get more efficient lighting. I was also thinking compact and to get it to look like an incandescent I would make it spiral and bend it with certain geometry, but it wouldn't be easy. My colleagues gave me many reasons why it wouldn't work.
From conception to prototype took up to two years, and my first compact fluorescent lightbulb was good. It's on display at the Smithsonian National Museum of American History in Washington, D.C. Today's spirals look very similar to the first one.
You invented the CFL in 1975. Why did it take so long for it to reach stores?
A number of reasons. There wasn't enough money for GE to do the CFL. It got delayed. Time goes on and there were other projects. In 1985 we tried to do the CFL, but bending it was very difficult because there wasn't automated equipment. GE thought the CFL was a good bulb but too expensive to make. The bending was done manually and the other parts were automated. The only place in the world where CFLs could be made and sold at a reasonable price was China. In the end, GE wasn't the first to bring CFLs to market.
Were there any problems with the first CFLs?
One big problem was that they operated with a high-frequency electronic ballast. People complained they were having problems with their TVs and they'd take them back to the store. The output frequency of the CFLs was the same as the frequency from the televisions and was causing interference. Once we identified the frequencies being used, the remote-control people designed around it. Interference is no longer a problem, but that slowed down sales of CFLs.
Are spiral CFLs still bent by hand?
TCP, a big lighting manufacturer for which I consult, recently automated the bending of the glass, so now it's very profitable. TCP makes something like 1.5 million CFLs a day.
What do you think of today's CFLs?
There are no major problems. The only issue is to continue to make them better. The color, per se, is not a major problem. There can be problems if there are quality-processing concerns, but it's not design problem.
Isn't mercury a concern when a CFL breaks?
The Environmental Protection Agency has put fear into people that these bulbs are toxic and you should cut out your rug if one breaks. In my experience, it's not a problem. The biggest hazard is the broken glass. We're looking for scientific data that backs up that they're hazardous but we haven't found it. Mercury can be a neurotoxin if used incorrectly. If it gets into your system in a quantity and over prolonged time, then it's a problem. But every element is a problem if used incorrectly.
Why did you use mercury in your CFL?
Mercury is by far the best way to excite the phosphorous that ignites the light. In the first bulb I probably put in a lot, about 20 milligrams. (Ed: Today's Energy Star-qualified bulbs have less than 5 milligrams each.)
Are CFLs here to stay, or are LEDs the future?
There's a lot of progress being made with LED lighting. But for general lighting, CFLs will be here for a long time. In order for the LEDs to be good as CFLs, there still have to be major breakthroughs.