Demise of Incandescent Light Bulbs May Increase Energy Use

“A light bulb factory closes in Virginia as mandated fluorescents are made in China. It’s now a crime to make or ship for sale 75-watt incandescent bulbs in the European Union…. The General Electric light bulb factory in Winchester, Va., closed this month, a victim, along with its 200 employees, of a 2007 energy conservation measure passed by Congress that set standards essentially banning ordinary incandescents by 2014.” notes Investor’s Business Daily.

Incandescent light bulbs waste much electricity by producing heat. Many governments have or are about to phase out incandescent light bulbs under the belief that other, more energy efficient lighting technology will reduce energy use.

Currently, artificial lighting uses 6.5% of the world’s primary energy, which translates into about 16% of world electrical generation, and it consumes about 0.72% of global GDP.

A new study conducted by Sandia National Laboratories, and funded by the U.S. Department of Energy, takes exception to the assumption that newer technology will mean lower energy consumption.

The study authors note that “Lighting technology is evolving rapidly. Filament-based incandescent lighting is giving way to gas-plasma-based fluorescent and high-intensity discharge technology, and over the next 10- to 20 years, may give way to solid-state technology.”

It has been assumed “that consumption of light is relatively insensitive to the cost of light, and that evolution of lighting technology resulting in an increase in efficiency and a decrease in cost

leads to a decrease in the consumption of energy rather than an increase in the consumption of light.” The authors of the new study, however, reject that assumption and instead assume “a sensitivity consistent with simple extrapolations of past behavior into the future.” They also analyze the interplay between lighting, human productivity, and energy consumption.

The paper concludes: “A principal conclusion is that there is a massive potential for growth in the consumption of light if new lighting technologies are developed with higher luminous efficacies and lower cost of light. A secondary conclusion is that this increased consumption of light has the potential to increase both human productivity and the consumption of energy associated with that productivity.”

If this analysis is correct, then government policy to phase out incandescent light bulbs will have the unintended consequence of increasing energy use, just the opposite of what was intended.

Citation: J. Y. Tsao et al, 2010, Solid-state lighting: an energy-economics perspective, J. Phys. D: Appl. Phys. 43 354001; doi: 10.1088/0022-3727/43/35/354001

The paper is highly mathematical in justifying its conclusions, but if you are game, you can read the paper here.