An LED lighting revolution is underway. LED light bulbs are rapidly increasing in performance capability and decreasing in price. Last year, A19 format LED light bulbs, the common household format, sold in the range of $20 to $60. There was a strong correlation between price and quality. This year, top-of-the-line bulbs, such as the LG bulb, can be purchased for $10.
LED light bulbs have about the same efficacy as compact fluorescent light bulbs (CFLs), 50 to 60 lumens/watt. However, LEDs keep getting better while CFL technology has plateaued. The 7.5W LG bulb emits 485 lumens. This corresponds to 65 lm/W. It’s a 40W equivalent. At the same 485 lumens, the old fashioned 40 W light bulb would offer only 12 lm/W, five times less.
The LG 7.5W LED A19 Light Bulb LB08D830L0A.E50JWU0 in and out of its
packaging (click on image to enlarge).
The quoted lifetimes are PREDICTED reliability based on specific temperatures, perfect construction with no flaws, and no temperature cycling. The usual bathtub curve applies: some will fail very soon (infant mortality) due to poor construction.
If LED bulbs really last as long as is claimed, then they're actually not more expensive in time-averaged price than CCFLs.
A few years ago, I replaced all my incandescents with CCFLs, all of which claim to have 10,000 hours life. At first I bought brand name expensive ones, but after replacing a few of those after just a year or so, I started buying the cheap no-brand made in China CCFLs, which are now only $2-$3 each. They seem to also only last a year or so, which is no worse than the expensive ones.
The no-brand LED bulbs seem to go for about $20 for a 60W equivalent light output, and they claim 25,000 hours life.
It all comes down to the claim vs. the reality.
How about we all stop using science to drive polotical agenda. This technology is wonderful, but the promises of savings to the consumer are absolute BS. see:
Good stuff. The CFLs are great because they produce more light then heat -efficiency! The LEDs will produce heat but seam to have the efficiency. I found it easy to replace all of my incandesent lights with CFLs and only wish they were US made. I will try a few of the LEDs as the CFL's fail. New formats like overhead lighting or panels may come with time. Remember tube circuits and how the tubes were replaceable and now we had solid state and we no longer expect to replace active circuits.
David Patterson, known for his pioneering research that led to RAID, clusters and more, is part of a team at UC Berkeley that recently made its RISC-V processor architecture an open source hardware offering. We talk with Patterson and one of his colleagues behind the effort about the opportunities they see, what new kinds of designs they hope to enable and what it means for today’s commercial processor giants such as Intel, ARM and Imagination Technologies.