On average a traditional cathode ray tube (CRT) television set uses 100 watts of power when in use and about two watts on standby.
Newer LCD and plasma screens are higher users of energy, with the largest models consuming up to 400 watts when in use and about four watts on standby
Never Keep your televison on Standby mode when you are not waching switch off It from Source and make it a habbit.
DLP projection televisions are considered better at energy saving than LCD and Plasma TV.
Don't place your TV near the AC/ AC thermostat. The heat generated by the television, sensed by the thermostat, might cause the air-conditioning unit to run longer than necessary…and you know how A/Cs Consume so much power.
Lower your TV's brightness setting.
Look out for brands and manufacturers that seem to have the power bill-conscious consumers in mind.
Source : http://www.power-saver.blogspot.com/