How much 450 watts bulb take?

A 450-watt bulb consumes 450 watts of electrical power when it is turned on. If it operates for one hour, it will use 0.45 kilowatt-hours (kWh) of energy. The cost of running the bulb will depend on your local electricity rates, which are typically charged per kWh. For example, if the rate is $0.12 per kWh, running the bulb for one hour would cost about $0.054.