LED Bulbs on Campus Stand to Save Electricity and Money

As part of a college-wide effort to replace most lightbulbs on campus with efficient LED bulbs, in August a team of community members led by head electrician K.P. Peterson replaced the halogen bulbs in Ragle Hall with significant results. Early data analysis comparing the first two weeks of October in 2018 and 2019 reveals an average drop of 47.4 kilowatt-hours (kWh) a day of usage for that period which, if this is typical for the year, could lead to a savings of more than $2000 a year.

“We replaced about 50 bulbs in all, which might not seem like a very big job, but it turns out that ceilings can be quite high,” said Matt Ollis, math professor and one of the bulb-changing team, who analyzed the data. “Atempting hypothesis is that the changes between October 2018 and October 2019 are completely driven by the bulb project, and who can resist a tempting hypothesis?”

At face value, the energy required to run the new bulbs at full power should be a significant decrease, from around 8kW to 1kW—so if the lights are on for a full hour the college saves 7kWh. Another explanation for the observed change could be changes in usage patterns from one year to the next, and further analysis with a larger data set will be necessary to confirm these early findings. The story is further complicated by the fact that Ragle Hall accounts for only a fraction of the total electricity usage in the Serkin Center, so variations from other parts of the building could contribute to variations from one year to the next.

“Serkin is just one building, so we hope that our continuing efforts at changing to LED bulbs yields similar results in other buildings across campus,” said Jenny Ramstetter, biology professor and chair of the Environmental Advisory Committee, which has helped implement the project. “We are currently offering LED lightbulbs to all students for desk lamps in their dorm rooms, and looking into replacing the house lights in Whittemore Theater.”