Small signs can add up to big energy use.

If it seems like there are exit signs everywhere, it's because there's an estimated 100 million exit signs in the United States consuming between 30 and 35 BILLION kWh of energy each year. Most use incandescent bulbs, which use large amounts of energy and require more maintenance.

The typical exit sign with incandescent bulbs uses 2 - 20 watt bulbs. The signs are lit 24 hours a day and 365 days a year. Let's do the math for a single sign.

2 X 20 watts = 40 watts X 24 hours = 960 watt hours

960 X 365 days per year = 350,400 watt hours

Electricity is billed by the amount of kilowatt hours (kWh) used and the national average cost is $0.08 per kWh (adjust this cost for your school/business)

To convert watt hours to kilowatt hours (kWh), divide watt hours by 1,000.

350,400 watt hours divided by 1,000 = 350.4kWh X $0.08 per kWh = $28.03

Now let's look at the other costs.

The incandescent bulbs cost approximately $3.00 each and the sign has 2 bulbs. 2 X $3 = $6
The bulbs have to be replaced an average of 3 times each year. 3 X $6 = $18

The bulbs don't replace themselves so we have to add the labor cost.
Figure 1/2 hour per change or $10 labor per change X 3 = $30

Our annual total cost now includes

How many signs are in your school?

If these signs were replaced with energy efficient signs which use light-emitting diodes (LED), the energy savings will pay-back the replacement costs many, many times over.

A typical LED exit sign operates using 5 watts or less. The life expectancy of an LED sign is more than 80 years.

LED Costs:

Electricity: 5 watts X 24 = 120

120 X 365 = 43,800 watt hours or 43.8kWh X $0.08 per kWh = $3.50

The US Postal Service has announced that it plans to replace 15,000 exit signs in post
offices across the country with new energy-efficient exit signs that use less than 2 watts and last over 20 years.

"These exit signs meet the Energy Star specifications for energy efficiency and will save the Postal Service over $300,000 in energy costs annually, said Charles Bravo, manager, USPS Environmental Management Policy. Additional savings will result in maintenance work hours in lamp replacement.

"The Postal Service is pleased to embark on this energy-saving initiative which is visibly supported by both the Department of Energy (DOE) and the Environmental Protection Agency (EPA)," said Bravo. "The use of these energy efficient LED exit signs is good for our business, our customers, our employees, and our environment."

YOUR School

Why not start an inventory of exit signs in your school? Enlist the help of your school custodian in determining bulb types and watts used. If other schools will cooperate you could survey the entire district.

Now What?

The results of your inventory should provide you with information on potential energy savings that should be of interest to your local School Board. Why not develop a short, concise presentation on energy efficiency

For more information, check out the Energy Star Exit Sign Program. The web site includes a energy calculator to help you estimate energy use, costs and savings. It also lists Energy Star Exit Sign Manufacturers.

Your Home

While at the Energy Star web site you can also check out the information on Energy Star appliances, electronics, lighting, windows and more.