LED Bulbs for EXIT Signs

In February 2011, the Green EDGE Fund purchased 100 LED light bulb kits, to be installed in EXIT signs on campus that use incandescent bulbs.

round premise:

An audit of every building on campus revealed that all of the EXIT signs remaining using incandescent bulbs could be converted to more efficient LED bulbs with 100 kits. Each EXIT sign is comprised of one kit, which contains two bulbs. Combined, the two LED bulbs use 2.8 Watts, compared to 50 Watts for incandescent bulbs. As EXIT signs are on for 24 hours a day and seven days a week, this project will have a timely payback period, which is a requirement of Efficiency Loans.

Cost-benefit estimation:
The EDGE Fund purchased 100 LED kits, which cost $14 each. Assuming that electricity costs $0.10 per kWh, the electricity savings for 65 signs will be $2687 annually. Assuming that 1.8 pounds of CO2 are emitted for each kWh used in Ohio, the carbon savings for 65 signs will be 13193 pounds of carbon annually. As the new bulbs are supposed to last for 50,000 hours, the life expectancy of the project is about 5.7 years. The lifetime monetary savings of this project are thus $15,319.

Additional benefits:
In addition to the annual monetary and carbon savings this project brings, LED bulbs last ten times longer than the incandescent bulbs. This means that they will have to be replaced less frequently, saving labor costs.