Sunday, March 7, 2010

LCDs LEDs and CRTs

How LCD Monitors have helped reduce carbon emissions

In the past decade LCD monitors have gone from an expensive option to becoming the most common technology used for personal computers. Cathode Ray Tube (CRT) monitors have virtually disappeared from stores and are almost nonexistent in offices and homes in the developed economies. LCD Monitors were adopted after their price became competitive because they take up less space, offer an improved image, and last just about forever. I have a 19 inch LCD monitor I bought nine years ago and it still operates perfectly and looks just as modern as the LCD monitors that are sold today. Last night my wife and I watched a pay per view movie called The Informant. The movie was made in 2009 but was set in the early 1990s. There are many office scenes in the movie and the desk top computers have CRT monitors that now look as old as a Remington Type Writer. In a future blog I will opine about Lysine and Archer Daniel Midland, (ADM) the company that was the focus of the movie. Yeah ADM is also the villain that visited Bio-Ethanol on us in a big way.

Back to the blog about LCD technology and its energy savings and therefore lowered carbon footprint. A 19 inch LCD monitor uses approximately 50 watts of electric power. The same size CRT monitor uses 100 watts of power. Hence the resulting power savings of approximately 50 watts. The typical usage of the monitor is eight hours a day. This means each and every day the LCD monitor saves the user 400 watt hours of purchased electricity. Since their introduction just over a decade ago more than one billion LCD monitors have been sold and perhaps as many as 90% of these monitors still are in operation. In 2009 176 million LCD monitors were sold worldwide up from 170 million in 2008. For the example of the amount of energy saved in a year I will use one billion monitors running 8 hours a day and saving 50 watts of power each. This equates to 400 million kilowatt hours of saved electricity worldwide a day. The average power generation station in the world emits approximately 1.5 pounds of carbon dioxide for each kilowatt hour that is generated. Therefore some 600 million pounds a day of carbon dioxide emissions are eliminated through the substitution of LCD monitors for CRT monitors. This equals over 109 million metric tons a year of lowered carbon dioxide emissions. This is approximately the yearly emissions from either Belgium or Vietnam. This link provides the listing of the emissions form all countries

Belgium is a developed economy with a population of 10.7 million people. Vietnam is a developing economy with a population of 80 million people. The LCD computer monitor has therefore been very effective in reducing carbon dioxide emissions. Another way of comparing this information is that the introduction of LCD computer monitors reduced carbon dioxide emissions equal to the removal of 18 million mid sized cars that have a fuel economy of 20 miles per US gallon and travel 12,000 miles a year. Older LCD monitors had a fluorescent backlight that are now being replaced with light emitting diode (LED) back lights. These LED lit LCD monitors are even more energy efficient. Some 50 LEDs are used to back light a 19 inch LCD monitor. LEDs will prevail as the technology for lighting monitors, TVs, homes, streets, offices, stores, and vehicles. In 2009 some 63 billion LEDs were sold worldwide. This increased from 57 billion units in 2008. LED back lit LCDs are a technology that the Green Machine applauds.