One of the features of the most recently developed flat panel TVs is the rather large amount of electrical power they demand. Some of it goes to produce the gorgeous picture you crave, but most of it is either radiated out the front, convected out the top or blown out the back.
For instance a very popular LCD flat panel pulls almost 300 watts, and if you want to go to a large screen, LCD, you should be prepared to enjoy over
500 watts of comfy cozy warmth. Some of the Plasma panels approaching 60" pull over 700 watts. Plasma is particularly hoggish compared size to size against LCD.
If you are thinking of replacing a 5-year-old big screen, or moving up in screen size to something where you can sit back and enjoy the superb detail, and want to keep your power demand down around 120 watts, you might just look into LCD DLP. Your air conditioner and particularly your wallet will thank you.