LED vs. CFL: Life-Cycle Study Shows a Close Race, but LED Likely to Take the Lead

led vs cfl lightbulbs photo

"Only 2% of total energy consumed by LED-based lamps is used in their production."
When trying to determine the greenest option among products, it is important to take into account the whole life-cycle of the thing; the manufacturing process, how it is used, and the disposal at the end of its life. The U.S. Department of Energy has already released a few life-cycle assessments (LCA) of LED lights (see here and here for a Carnegie Mellon study), and LED maker Osram has just released a new LCA study conducted by the Siemens Corporate Technology Centre for Eco Innovations. Their conclusions are pretty interesting...
Osram LCA led cfl bulbs image

It takes 25 incandescent lightbulbs, 2.5 CFLs and 1 LED lamp to reach the 25,000 hours benchmark.
LED Lights LCA Studies
Both the Carnegie Mellon and Osram studies found that production is a relatively small portion of the total life-cycle impact of the different lightbulb technologies. From the Osram study: "[with LEDs and CFLs] over 98% of the energy used is consumed to generate light. Less than two percent is allocated to production. This dismisses any concern that manufacturing of LED particularly might be very energy-intensive."

When comparing LEDs that produce about 30 lumens/watt to CFLs, the results are very close, and for all practical purposes, we can say that LEDs are as energy efficient as CFLs. But LEDs are still improving and they do not contain mercury, which makes their disposal less hazardous than CFLs. The Carnegie Mellon study predicts that efficiencies of 150 lumens/watt are possible for LEDs:

led cfls carnegie mellon lca image

led cfls carnegie mellon lca image

This would make LEDs take a significant lead and assure their dominance over CFLs, as long as prices can be brought down. Even if 150 lumens/watt isn't attainable in the near future, a doubling to 60 lumens/watt would leave CFLs in the dust.

led lightbulb photo

Conclusion: LEDs are Competitive, Likely to Get Better
So for now, the conclusion is that based on life-cycle assessments, LEDs are about as energy efficient as CFLs when you take into account their whole life-cycle. But that seems likely to change since LED lighting technology is still maturing and improving quite fast and fluorescent technology is unlikely to improve enough to catch up.

Via Bits, PRNEwsWire
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