Work out light bulb replacement savings instantly with clear inputs, formula shown and shareable results.
Replacing a 60 W incandescent with an 8 W LED saves 52 W for every hour it burns. Across fifteen bulbs at four hours a day that is 1,139 kWh a year — well over three hundred pounds — with a payback measured in weeks rather than years.
Lighting saving
saved kWh = (old W - new W) x bulbs x hours x 365 / 1000; payback = bulb cost / annual saving
The ones on longest: kitchen, living room and hallway. A bulb used ten minutes a day saves almost nothing however inefficient it is.
The LED itself often does, but the driver electronics frequently fail sooner, especially in enclosed fittings where heat builds up.