Frigid Ithaca means expensive heating bills. Based on the results of a recent study by energy efficiency specialist Mark Pierce, an extension associate in the College of Human Ecology, Ithaca residents battling the cold would save money using their central heating system instead of electric space heaters.

To determine which resulted in lower costs, Pierce compared the effects of the two heating systems on the same house. He found that, contrary to popular belief, home heating systems are more efficient than electric heaters.

First, Pierce calculated the cost of maintaining a 1,200-square-foot, three-bedroom house at 70 degrees for three hours. He then reduced the heat of the same house to 60 degrees, while warming one of the bedrooms to 70 degrees with a space heater.

Although decreasing the temperature by 10 degrees resulted in a savings of 50 to 80 cents, turning on the electric heater raised the cost by 52 cents. The electric heater thus negated any savings provided by lowering the heat in the house.

Pierce said that electricity accounted for the additional cost, as it is about twice as expensive as the fossil fuels that power central heating.

Pierce said he decided to conduct the study after being unable to answer a question he was frequently asked: “Can I save money if I turn my central heating system down and use a space heater?”

“You can go online and there is some sort of basic advice from the Department of Energy and those kinds of things, but I couldn’t find any analysis that had been done,” Pierce said. 

Pierce decided to fine concrete results. His goal was to create a model to simulate the living situations of most New Yorkers, who pay about 17 cents per kilowatt-hour for heating in houses that are “relatively poorly insulated.”

Pierce said his mother’s home was designated as an appropriate site of the experiment because its structure is very common. Using particularly low insulation levels made his analysis all the more persuasive, Pierce said, because “the better insulated the house and the more efficient it is, the less likely it is that turning your heating system down and using a space heater would be effective.” 

Since Pierce had performed several tests prior to the study, he said the rest of the procedure involved merely plugging in the data using computer modeling and mathematical models and calculations.

For the past seven years, Pierce and his colleague, Prof. Joseph Laquatra, design and environmental analysis, have worked on the Consumer Program for Residential Energy Efficiency, a partnership between Cornell and the New York State Research and Development Authority designed to educate homeowners about energy efficiency. The program also helps homeowners find ways to reduce energy consumption costs. 

“We work with homeowners, tenants, builders, real estate brokers and others to broaden people’s understanding about energy use in homes,” Laquatra said. 

Like Pierce, Laquatra said that electric heaters are not the optimal choice in terms of efficient heating. 

“You really should look at what is inefficient about your central heating system,” Pierce said. “If your central heating system is operating at peak efficiency, space heaters shouldn’t be necessary.”