40 years later: Fluorescents are catching on

Inventive minds worked over and over for the past 200 years to produce incandescent and  fluorescent electric light bulbs. Fluorescent will overtake incandescent in time.

It was five years ago when I hired a painter to paint the outside walls of our house. He recommended that I go to Great Barrington and visit an area hardware store where the paints he needed were sold. I looked around in the hardware store and suddenly saw a batch of shelves with fluorescent lamps that were on sale for only 50 cents a bulb. I remembered seeing these bulbs before in various hardware stores, but the prices were much higher, around $3 to $4 a bulb.

I decided to buy a few and took six fluorescent bulbs home with me. I replaced six incandescent bulbs with these new ones and was very pleased with how they worked. The 60-watt fluorescent bulb used only 15 watts of electric power. It saved money. And even better, it had a life of 10,000 hours compared with the life of 1,500 to 2,000 hours for the incandescent bulb.

I returned to the hardware store and bought 30 fluorescent bulbs at that sale price to replace all of the incandescent ones in our house. And it caused me to devote some time to research about light bulbs, both incandescent and fluorescent.

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The incandescent light bulb used now in just about every house and factory and store and train was first invented back in 1802 by Humphrey Davy. While the original bulb was not very good, it was the basis for 22 other inventors to improve over a period of 75 years. Then came inventor Joseph Wilson Swan and especially Thomas Edison. Edison started his research for developing a practical incandescent.  He filed his first patent application in this field, titled “Improvement of Electric Lights,â€� in 1878.

After many experiments with platinum and other metal filaments, Edison returned to using a carbon filament and his first successful test was done in October 1879. He continued to improve this design and then filed a new patent application for an electric lamp using “a carbon filament wire.� Several months after this patent was granted, Edison discovered that such a filament could last more than 1,200 hours, an enormous improvement over all earlier inventions.

There was a series of fights between Edison and Swan, but ultimately Swan decided to turn over to Edison all the rights to create and sell these incandescent lamps. In 1881, the Savoy theater became the first public building in the world to be lit entirely by these electric incandescent lights. But things started changing a number of years ago.

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Alexander Becquerel, a French physicist, is believed to have started investigating what he called fluorescence and phosphorescence as the source of light in bulbs back in 1857. He thought about building fluorescent light bulbs. They were similar to what are being built and used today. Then, in 1901, Peter Hewitt received a patent for his invention of the fluorescent lamp. No filaments are used as in the incandescent lamp. The two wires connected to the AC power line transmit power into the fluorescent bulb and heat up the mercury and an inert gas, usually argon. The bulbs also contain a phosphor powder coating on the inside of the glass bulb.

When you turn on the power, the energy within the tube causes the mercury to change from a liquid to a gas, and it lights up in the ultraviolet wavelength range. Since we cannot see this frequency of light, the phosphor power on the inner surface of the bulb converts that to bright visible light. Phosphors are substances that give off light when they are re-exposed to energy as in the fluorescent bulb.

The life of the fluorescent bulb is indeed 10,000 hours, five to six times longer than the life of the incandescent bulb. What a difference! And, when you compare power used to produce light, 60 watts in the incandescent bulb, compared with the same light coming out of the fluorescent bulb, the fluorescent bulb uses only 15 watts of power to produce the same light intensity as the 60 watt incandescent bulb. What a saving! Only one-fourth the power delivers the same brightness of light. These two factors, power used and life span, make the fluorescent light bulb the one to install, as soon as possible.

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There are two other differences between these two types of bulbs. Most fluorescent bulbs are spiral in shape. And the cost of a 60-watt fluorescent bulb is usually about two or three times the cost of a 60-watt incandescent bulb. Even with that difference in price the fluorescent bulb makes more sense to use than the incandescent bulb. But it is taking time, even though the fluorescent bulb has been on the market for more than 40 years.

Part of the problem for consumers could be the cost of compact fluorescent bulbs compared to the traditional incandescent. In doing a survey of hardware stores in our Tri-state region as to the pricing on 60-watt compact fluorescent spiral bulbs, the prices ranged in general from $1.99 each all the way up to $8.99 each.

However, there are energy-efficient lighting sales sponsored by Connecticut Light and Power (CL&P) such as the one held at Noble Horizons in Salisbury July 8, where bulbs cost only around a dollar each. And, the standout in locally owned retailers was Aubuchon Hardware in Great Barrington, where 60-watt fluorescent bulbs have been priced at 50 cents per bulb to 90 cents per bulb for the past five years. The cost there this week: One make is 79 cents, one make is 99 cents per bulb.  

I am, as you can tell, a big supporter of using compact fluorescent bulbs as opposed to incandescents. As I have thought about the savings in power and cost over the years, I have shared with several of my friends the best pricing I could find for these bulbs and encouraged them to switch to compact fluorescent lighting. Now, they have all stocked up on fluorescent light bulbs, just as I have done. The best part: In the past five years, not one single fluorescent bulb has gone sour and they all continue to provide bright light.

Sidney X. Shore is a scientist, inventor and educator who lives in Sharon and holds more than 30 U.S. patents.