# How much does it cost to leave a light on for a week?

The average light bulb uses about 60 watts of electricity. So, if you use a 60-watt light bulb and leave it on for one hour, it will use 0.06 kilowatts of energy. If you leave the light on for one day, it will use 1.44 kilowatts of energy. If you leave the light on for one week, it will use 10.08 kilowatts of energy.

At the current rate of \$0.11 per kilowatt hour, it will cost you \$1.12 to leave a 60-watt light bulb on for one week.

However, the cost of electricity is not the only factor to consider when deciding whether or not to leave a light on. There is also the cost of the light bulb itself. A 60-watt incandescent light bulb will last about 1,000 hours before it needs to be replaced. So, if you leave the light on for one week, you will use up one-seventh of the life of the light bulb.

Assuming that you replace the light bulb when it burns out, the cost of the light bulb is \$0.01. So, the total cost of leaving a 60-watt light bulb on for one week is \$1.13.

Of course, the cost of electricity and the cost of the light bulb are not the only costs to consider. There is also the opportunity cost of using the electricity to power the light bulb. For example, if you use the electricity to power the light bulb, you cannot use it to power a television.

The opportunity cost of using the electricity to power the light bulb is the cost of the next best alternative use of the electricity. In this case, the opportunity cost is the cost of powering a television. The average television uses about 100 watts of electricity. So, if you use 100 watts of electricity to power a television for one hour, it will cost you \$0.11.

If you leave the light on for one week, it will cost you \$1.13 to leave the light on. If you use the electricity to power a television for one week, it will cost you \$2.20. Therefore, the opportunity cost of leaving the light on is \$2.20.