Shedding light on true cost of bulbs

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Bargain shoppers beware: The savings energy-efficient light bulbs offer won't be found at checkout.

Despite the overall savings that energy-efficient light bulbs offer, human brains are programmed to favor immediate costs over long-term savings. Consumers will be more likely to finally make the switch to more expensive energy-efficient light bulbs, such as LEDs and CFLs, if they know these bulbs cost less to operate per year, according to a study published last month by a team of Carnegie Mellon University researchers.

"We found the bulbs had a better fighting chance if consumers were aware of savings during buying," said Jeremy Michalek, CMU associate professor of mechanical engineering and of engineering and public policy as well as director of the CMU Vehicle Electrification Group.

Energy-efficiency standards for light bulbs were established by federal law in 2007. More efficient 40- and 60-watt bulbs are mandated starting this year, meaning traditional incandescents that give off most of their energy in heat will no longer be produced.

The aim is to drastically reduce the "energy gap" -- the difference between the energy being consumed today and the amount of energy that would be consumed if energy-efficient technologies were adopted. Researcher Ines Azevedo, assistant professor of engineering and public policy, said she wanted to investigate the gap and what behavioral and policy reasons explain it. She is also co-director of CMU's Center for Climate and Energy Decision-Making.

She questioned why consumers often don't buy more energy-efficient bulbs.

The two higher-efficiency types of bulbs are comparable in their lifetime cost. CFLs (compact fluorescent lamps) cost less than $10 to purchase, while LEDs can be more than $30 upfront, but the lifetime of LEDs, which cost less to operate annually, is estimated to be more than 10 years longer than CFLs.

A 2010 study by the Department of Energy found that the residential sector accounts for 25 percent of the country's lighting energy consumption and was the least energy-efficient because of continued use of incandescent bulbs.

"There's a critically large discussion about the potential in technologies and why people aren't taking this opportunity," Ms. Azevedo said.

The team of CMU professors -- Ms. Azevedo, Mr. Michalek and Wandi Bruine de Bruine -- and doctoral student Jihoon Min designed an experiment to study the factors that were hindering the switch to more efficient lighting and better understand how consumers make their choices.

The experiment's subjects were asked to choose light bulbs from different types, prices, brightness, power, colors and lifetimes. The first phase offered hypothetical options on a screen, and the second phase allowed the subjects to select from actual light bulb packages. When subjects were provided with operating costs, the researchers found them more likely to choose the energy-efficient bulbs.

Renters and low-income consumers are two groups who are more reluctant to adopt the new technology, according to the study. Renters whose landlords pay utilities have a lower incentive to pay attention to energy consumption and don't have a financial reason to pursue long-term savings. Low-income consumers are more interested in the timing of savings. High-income consumers are willing to invest more at the time of purchase in order to save in the future.

The results of the study don't indicate that attitudes by some consumers can't change, Ms. Azevedo said, adding that they confirm the potential capability of new lighting policies.

The Federal Trade Commission required new labels on light bulb packages at the beginning of 2012. The design includes the estimated annual energy cost of the bulb, which the study found to be beneficial.

Lighting accounts for one-fifth of the electricity consumption in the United States, so converting to the new technology is a "major step in using the energy we have more efficiently," Mr. Michalek said.

The transformation in the United States is slowly starting. People are beginning to "trade off" initial savings to help themselves and society in the future when they choose energy-efficient bulbs, according to Mr. Michalek.

"We know they are definitely willing to pay more to help the environment, but how much more?" he said.

In Ms. Azevedo's native country of Portugal, "almost every bulb is CFL." Household incomes are lower, and electricity costs more than in the United States, she said.

"They really have a reason to make a switch."

Sara Payne:

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