If I have 2 42w cfls and 2 20w cfls. and they run 12/12 how much would that draw on a bill.... Because my roommate is trying to say I ran the bill up 50 bucks in a like half month.... With that and one air pump a small one at that for a dwc bucket... So hes trying to make me pay 50bucks for a month where I ran the setup for half the month. So I pretty much pulled my whole setup at my house and move it all back to my old spot. How can I calculate the watts? I dont know what my rate per w is tho... I live in the southeast in that helps.
Electrical usage is figured in KWs (kilowatt hours). Go to your power bill and find out how much you pay per kilowatt hour. However, you are correct--those light will not increase your bill $50. The wattage of the air pump is probably inconsequental, probably about 3 watts or so. Here is the math: 2 42W and 2 20W gives you 124 watts per hour. Multiplying this times 12 hours a day gives you 1488 watts a day. Dividing this by 1000 to find your daily kilowatt usage-1.488 kilowatts a day. Multiplying this by 30 will give you your kilowatt per month-44.64 kilowatts a month. I pay about $0.07 per kilowatt. So, your lights would cost me about $3.12 a month to run. If your electricity bill is excessive, it is not because of your CFLs.