"Energy Efficiency is at the heart of energy affordability." Tony Earley, Chairman, CEO and President of PG&E Corporation


Research Confirms Advantages of LED Lights

By Jonathan Marshall

The official verdict is in: Light-emitting diodes (LEDs) are not only the most energy efficient source of artificial illumination but the most environmentally benign as well.

That’s according to a new study released by the Department of Energy, which examined all the steps needed to fabricate, ship, operate, and dispose of LEDs, compact fluorescent lights (CFLs), and traditional incandescent lighting.

The Renwick Gallery Grand Salon in the Smithsonian American Art Museum used LED replacement lamps in approximately one-third of the display track lighting located near the simulated skylight. (Photo by Scott Rosenfeld – Department of Energy.)

A previous DOE assessment of relative energy use, including manufacturing and transport, showed LEDs leading the pack by just a hair. Ever-so-closely behind were CFLs, followed as a distant third by incandescents, which hog nearly four times as much energy over their total life-cycle. Not only do incandescent bulbs require much more energy per lumen-hour (a measure of light output over time), it takes 22 of them to last as long as one LED.

Learn more about the California model for energy efficiency

The new environmental study gives LEDs a clear lead over CFLs on almost every measure, including toxicity, ecosystem damage, global warming, and ozone depletion. LEDs lag only slightly on landfill waste because of the large aluminum heat sinks needed to cool them.

And the performance gap is only going to get wider. At the pace manufacturers are improving their products, LEDs are projected to use only half as much energy by 2015 as they did in 2011, making them the uncontested efficiency leaders.  By 2017, their environmental footprint is likely to be 70 percent smaller than today’s CFLs.

“Environmental impact reductions on the order of 3 to 10 times are possible across the indicators through transitioning the market to these new, more efficacious light sources,” the DOE report notes.

To demonstrate the merits of LED lighting, DOE has been sponsoring retrofit projects around the country. One highly successful project at the Smithsonian American Art Museum paid for itself through energy savings in only 16 month. Energy use in one typical gallery plummeted by about 73 percent.

Art museums, like discerning businesses and homeowners, also appreciate the naturalism of light from LEDs. Humans apparently aren’t alone in that preference. In the weird-but-apparently-true category,researchers at Oklahoma State University have found that dairy cows produce 6 percent more milk with LED lighting than with harsher CFLs.

Rapid improvements in solid-state lighting technology are galvanizing PG&E’s energy efficiency program experts to help customers become more aware of the benefits of LED lighting as the high cost begins to come down.

On the residential side, PG&E now provides instant rebates of up to $10 for directional LED reflector bulbs (PAR20, PAR30 and PAR38) at retailers such as Home Depot, Lowe’s, Orchard Supply, and Costco.

Another DOE project tested LED streetlights along Franklin D. Roosevelt Drive in New York. (Photo by Ryan Pyle – Department of Energy.)

For commercial customers, PG&E offers rebates for LED downlight fixtures and retrofits, and LED exit signs. The utility also partners with distributors to promote LED refrigerated case lighting and LED exterior letter signage.

PG&E also has a highly successful LED Street Light Turnkey Replacement Service. Since the program began in 2009, PG&E has helped more than 60 cities convert more than 20,270 streetlights to LED lights, saving more than 8,500,000 kilowatt-hours every year and earning the cities rebates totaling $1,643,200.

In all, PG&E’s LED programs have helped cut power demand by 7 megawatts and reduced energy consumption by 56,000,000 kilowatt-hours over the period 2010-11.

Want to know more about choosing affordable, energy-efficient lighting for your home? Check out two new informative PG&E videos on YouTube here and here.

Email Jonathan Marshall at jonathan.marshall@pge.com.

This story originally appeared on pgecurrents.com.