Faculty Publications

A Student Research Project - Myth And Facts On Inrush Power Consumption And Mercury Content Of Incandescent Versus Compact Fluorescent Lights

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Journal/Book/Conference Title

ASEE Annual Conference and Exposition, Conference Proceedings


Green is now a new buzz word for many industries as well as on university campuses. The right amount and quality of light needed for the application is the first consideration in any lighting project. For over thirty years that authors know of, there have been stories - possibly "urban legends" - that someone has calculated that fluorescent lights consume more power in start-up than it takes to run them for up to an hour. For one able to understand the implications of these statements, they are absurd. However the stories and myths have circulated for many years. One way to combat these stories is to conduct a well-constructed experimental study to measure and compare the actual power consumed during the starting phase of these devices compared to steady state operation after the inrush has occurred, then publish the results appropriately. The power consumed should be compared for incandescent bulbs, compact fluorescent bulbs, T8 fluorescent tubes and possibly comparable (Light Emitting Diode) LED devices. Voltage and current, and thus power, would be measured during starting and running phases for each type of device. From that data, the time that it is more economical to leave the lights on or turn them off can be calculated to a fraction of a second for each type of device. A research team consisting of graduate and undergraduate students has investigated power consumption amount for incandescent and compact fluorescent bulbs during the inrush operation. This paper reports a number of case studies on inrush power consumption of incandescent and compact fluorescent bulbs. It also includes a brief study of another misconception - mercury content and environmental impacts. The United States Environmental Protection Agency (EPA) concludes that a typical compact fluorescent light (CFL) over the course of its life will put less mercury in to the environment than using incandescent light to produce equivalent lighting. Since coal is currently a major source of energy and a byproduct of its burning is mercury, therefore by requiring more energy to operate use of incandescent bulbs, is actually responsible for releasing more mercury into the environment than using CFL bulbs. It is expected that this student project results may help to clear the misconceptions about using more CFLs in our daily lives of residential and commercial lighting needs. This specific student project is adopted as a laboratory activity for 330:166g Advanced Electrical Power Systems class in the EET program. © American Society for Engineering Education, 2009.


Department of Industrial Technology

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