For Energy Savings, LEDs Outshine Solar Panels

A new report finds that replacing old lightbulbs with light-emitting diodes offers more energy savings than installing photovoltaics

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Homeowners looking to save electricity costs should replace all their incandescent light bulbs with LED-based lights instead of installing a small solar photovoltaic system, a report by J.P. Morgan shows.

Light-emitting diodes, or LEDs, will become mainstream over the next 12 months as improving technology and performance and higher subsidies lead to a rapid drop in costs, according to the report.

"The residential user still uses a lot of incandescent bulbs and has the greatest opportunity to reduce electricity costs and consumption," said Christopher Blansett, an analyst at J.P. Morgan.


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Both LEDs and solar photovoltaic systems would cut electricity consumption and monthly expenses as well as lower the impact of home lighting on the environment. But LEDs would pay back the investment much faster.

For a Northern California household in a region served by the Pacific Gas & Electric utility, a one-time investment of $1,150 for 30 LED-based light bulbs of 60 watts at a cost of $35 each would pay itself back within two and a half years even if the bulbs operate only three hours per day on average, the J.P. Morgan report says. This is much faster than some lighting experts' projections of payback ranging from five to 10 years.

Meanwhile, a small 2.5-kilowatt residential solar system would cost about $15,000 even after subsidies. That's 13 times more than the LED solution, and it would pay off in about 10 to 12 years, the report says.

"Although commercial, municipal and industrial users have generally made the transition to energy-efficient lighting, many residential users have not, usually citing poor lighting quality, low reliability and slow startup times that are associated with fluorescent technology," Blansett said. "Quality LED-based lighting has warm, rich color, is instant on and is indistinguishable from incandescent light by most users."

The power and reach of the 60-watt incandescent bulb
About 20 percent of carbon dioxide emissions associated with buildings in the United States are related to indoor lighting. Nearly 50 percent of all the lighting in the United States comes from 60-watt incandescent bulbs, with 425 million sold each year.

If all those lamps were LED equivalents, enough power would be saved to light 17.4 million American households and cut carbon emissions by 5.6 million metric tons annually, according to the Energy Department. New energy standards that go into effect in 2012 would effectively outlaw today's incandescent bulb.

LEDs are more than twice as efficient as compact fluorescent bulbs, currently the standard for greener lighting. They are made by companies with a long history of manufacturing incandescent lights, such as General Electric Co. and Philips, which are now promoting the new technology. A 12.5-watt LED bulb can illuminate as much as a 60-watt incandescent bulb and have a lifetime of as much as 30,000 hours. An additional advantage is that LEDs don't emit ultraviolet light, so they don't attract bugs.

So far, LEDs have been used predominantly outdoors. Cities like Ann Arbor, Mich.; Raleigh, N.C.; and Los Angeles, San Francisco and San Jose, Calif., are using LEDs for some street and parking garage lighting.

Along with residential use, higher-end retail and tourism sectors that continue to use incandescent lighting are prime targets for switching to LEDs due to high daily usage and obvious potential for savings.

Increasing utility subsidies for LED-based lighting will be a major factor in reducing the initial cost to the residential user and boosting acceptance for the technology, Blansett said. Typical incentives range today from $5 to $20 per LED light, but are still scarce, he said. "We believe as much as 40 percent of the LED lights sold in 2012 are likely to have some form of utility subsidy associated with them, helping to drive adoption in the residential sector."

Energy Star certification is typically required to qualify for a utility-related subsidy. "The list of LEd-based lighting products receiving Energy Star certification is growing rapidly," Blansett said.

Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC. www.eenews.net, 202-628-6500

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