Roughly, how much does it cost to have a lightbulb lit for 24 hours?

ask your service provider co.

they can identify these questions that need answers

Here is the formula-

wattage of bulb x local rates (check your bill)

__________________ = cost per hour

1,000

My rate is .06 per kw hour so a 75 watt bulb would cost me about .108 cents (11 cents) to run for 24 hours

around 20 cents

Watt is the whattage?..............errrrrr, sorry. What is the Wattage? (and which power company are you with? and on what sort of plan do you have with them?)