Cool How Much Electricity Does A String Of Christmas Lights Use Ideas. Your display size and choice of bulbs, whether incandescent or led, will influence your energy bill the most. Web if you want to use the lights on your christmas tree for the evening for, say, three hours, multiply 0.005 by three to get 0.015kw (your lights will use 0.015kw in those three hours).

Now for the measurement of power. Web 20 amp circuits support 2,400 watts (80% capacity is 1,920 max watts) how many watts do my christmas lights use? Web if you want to use the lights on your christmas tree for the evening for, say, three hours, multiply 0.005 by three to get 0.015kw (your lights will use 0.015kw in those three hours).