Invented and patented by Thomas Edison in 1879, the incandescent bulb comprises of a wired filament placed inside a glass bulb (“The History”). When electricity is provided to the filament, it heats up thereby making the bulb glow and emit light (“Incandescent, LED”). The wired filament of the incandescent bulb was initially made using carbon obtained from a cotton thread that was uncoated. This filament gave the bulb a lifespan of just 14.5 hours. Later, the carbon filament was made using bamboo, which gave the bulb a longer lifespan of up to 1200 hours (“The History”). Much later, in the year 1904, European researchers made the filament using tungsten and filled the glass bulb with nitrogen, an inert gas, to increase the efficiency of the light source. This is the composition of the modern incandescent bulb (“The History”).
Even so, only approximately 10% of the energy produced by the incandescent bulb is light, the rest being heat that increases electricity consumption of this light source. As a result, incandescent bulbs, which produce only 10-15 lumens of light per watt (Anderson) are considered as inefficient sources of light. Such bulbs normally have a lifespan of just between 750 and 1000 hours, with some long-lasting ones glowing for a maximum of 2500 hours. Incandescent bulbs are not very environment-friendly as their energy requirements are high, which indirectly leads to more mercury and greenhouse gases being released in the atmosphere. Also, these bulbs cannot be recycled, which increases material usage for their production (Verhaar).
Halogen Bulbs
In the 1950s, led by Alton Foote, researchers Elmer Fridrich, Emmett Wiley, Edward Zubler, and Frederick Mosby replaced the glass bulb of the incandescent bulb with fused quartz that was heat-resistant, used the tungsten filament for generating light, and added iodine, a halogen gas to increase the efficiency of the bulb. Thus, the halogen bulb, which is a version of the incandescent bulb, was born (“Inventing Six”). Modern halogen bulbs are made up of capsules that contain tungsten filament and halogen gas. Frequently, these bulbs also feature a special coating inside that recycles the heat generated by the bulbs to improve their efficiency (“Incandescent”), and an aluminized reflector that enhances the ability of the bulb to focus light (“Incandescent, LED”). Halogen bulbs generate 15 lumens of light per watt (Elliott), can last between 2250 and 3500 hours, are slightly more efficient than incandescent bulbs, and emit white and bright light that does not fade with time. However, they generate a lot of heat, and the higher-wattage halogen lamps can pose a fire hazard (“Incandescent, LED”). Since halogen bulbs are similar to their incandescent counterparts in design, they are not very energy-efficient, cannot be recycled, and are not very environment-friendly (Elliott).
Compact Fluorescent Light Bulbs
Invented first in the 19th century by Heinrich Giessler and Julius Plucker, the Compact Fluorescent Light (CFL) bulbs were initially called as Giessler tubes and consisted of glass tubes with vacuum through which electricity was passed to generate light. This design was improved by Edward Hammer in 1976 to create the modern CFL bulb that comprises of a spiral fluorescent tube (“The History”). The CFLs of today are made of glass tubes bent into compact, spiral shapes. The tubes are coated with phosphor, and filled with argon, an inert gas and mercury in small amounts. These bulbs are controlled by ballasts that alter the electricity flowing through the tubes, activate the gases within, and make them glow (“Incandescent, LED”). The CFL bulbs are extremely efficient, consume approximately 70% less energy as compared to incandescent bulbs (“Learn About”), and generate 65 to 70 lumens of light per watt (Anderson). They can also last up to 10000 hours and are therefore more cost-effective in the long run.
Since CFL bulbs are highly energy-efficient, their usage reduces energy consumption thereby decreasing greenhouse gas emission. Thus, the CFL lamps are environment-friendly. Although the mercury present in small amounts in these bulbs is a cause for concern, the ability to recycle these bulbs does away with this apprehension to a great extent (Verhaar). CFL bulbs are processed by separating the phosphor, mercury, and glass and metal components in special machines at low pressure to prevent mercury from entering the atmosphere. Each of these parts is then re-used to make more CFL lamps (“Recycling Lamps”).
Works Cited
“Incandescent Lighting.” Energy.gov. U.S. Department of Energy, n.d. Web. 25 Apr. 2016. <http://energy.gov/energysaver/incandescent-lighting >.
“Incandescent, LED, Fluorescent, Compact Fluorescent and Halogen Bulbs.” Consumerenergycenter.org. California Energy Commission, n.d. Web. 25 Apr. 2016. <http://www.consumerenergycenter.org/lighting/bulbs.html >.
“Inventing Six Modern Electric Lamps.” Americanhistory.si.edu. Smithsonian National Museum of American History, n.d. Web. 25 Apr. 2016. <http://americanhistory.si.edu/lighting/20thcent/invent20.htm >.
“Learn About CFLs.” Energystar.gov. Energy Star, n.d. Web. 25 Apr. 2016. <https://www.energystar.gov/products/lighting_fans/light_bulbs/learn_about_cfls >.
“Recycling Lamps.” Aircycle.com. Air Cycle Corporation, n.d. Web. 25 Apr. 2016. <http://www.aircycle.com/recycling/recycling-process/ >.
“The History of Light Bulb.” Energy.gov. U.S. Department of Energy, 22 Nov. 2013. Web. 25 Apr. 206. <http://energy.gov/articles/history-light-bulb>.
Anderson, Jessica C. “This Lightbulb Guide Will Finally Tell You the Difference Between CFLs, LEDs, and Halogens.” The Huffington Post. The HuffingtonPost.com, Inc, 12 May 2014. Web. 25 Apr. 2016. <http://www.huffingtonpost.com/entry/lightbulb-guide_n_5268642.html?section=india >
Elliot, Tim. “Halogen Lights Look Good But Can Cost the Earth.” The Sydney Morning Herald. Fairfax Media, 26 June 2007. Web. 25 Apr. 2016. <http://www.smh.com.au/news/environment/halogen-lights-look-good-but-can-cost-the-earth/2007/06/25/1182623820498.html >.
Verhaar, Harry. “Why We Need to Get Rid of Incandescent Bulbs.” Eceee.org. European Council for an Energy Efficient Economy, Dec. 2007. Web. 25 Apr. 2016. <http://www.eceee.org/all-news/columnists/Harry_Verhaar/Bulbs>.
