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Authors reprise 2010 paper showing increased productivity from more efficient lighting

Jeff Tsao

JEFF TSAO (1120, above) and colleagues have published a follow-up paper in the journal Energy Policy regarding the productivity gains to be realized with LED lighting. The paper came after an initial article published in 2010 was misinterpreted in some media sources. (Photo by Randy Montoya)

In an unusual follow-up to the publication of a scientific paper, two researchers have reprised in the journal

Energy Policy

their groundbreaking finding that improvements in lighting — from candles to gas lamps to electric bulbs — historically have led to increased light consumption rather than lower overall energy use by society.

The same unexpected result they predicted in 2010, might also apply to light-emitting diodes (LEDs), poised to take over from the Edison light bulb as the next, more efficient light source of choice.

Increased light equals increased productivity

But the main point of Jeff Tsao (1120) and Harry Saunders (The Breakthrough Institute in Oakland, Calif.) was that, as three centuries have shown, increased light availability leads to increased productivity. Workers are no longer forced to stop shortly after nightfall, as they had in primitive, candle illuminated huts, but instead could continue producing through the night in homes, offices, factories, and even at outdoor locations not serviced by power lines.

Thus, the original paper drew attention to the increased productivity made possible by better lighting, rather than societal energy-savings mistakenly cited as a feature of improved lighting technologies.

But misinterpretations of the original paper by the widely read Economist magazine and the New York Times led to the confusion that Tsao’s team had shown that lighting efficiency improvements were not improvements at all. This is because no reductions in overall energy usage or overall lighting costs would occur.

The researchers’ upcoming article, titled “Rebound Effects for Lighting,” opens, “Our 2010 article on solid-state lighting in the Journal of Physics with several colleagues (Tsao et al, 2010) has generated considerable interest (and confusion, unfortunately) in the popular press and in the blogosphere. This communication seeks to clarify some of this confusion for the particular benefit of energy economists and energy policy specialists.”

The original article was titled “Solid-state Lighting: an Energy-Economics Perspective.”

The new article appears under “Articles in Press” on the Energy Policy website.

“We were motivated to publish something, even if short, in Energy Policy, because that journal serves a community very different from that served by the Journal of Physics, where our original article was published,” Jeff says.

“We thought that many in the energy economics community were still unaware of the work, and of the benefit — even when there is no direct energy-use savings — of energy efficiency and other welfare-enhancing technologies.”

Other authors of the 2010 article included Mike Coltrin, Jerry Simmons and Randy Creighton (retired). Harry Saunders is also associated with Decision Processes Inc. in Danville, Calif.

The work was supported by Sandia’s Solid-State Lighting Science Energy Frontier Research Center, which is funded by DOE’s Office of Basic Energy Sciences.