SAN FRANCISCO—Claiming a breakthrough in light-emitting diode (LED) technology, Cree Inc. Tuesday (Feb. 7) announced a new product that the company claims delivers twice the lumens per dollar of conventional LEDs and offers the highest performance in the industry.
Based on a new silicon carbide technology platform, the Cree's XT-E LED and the recently released XB-D LED addresses the largest obstacle to mass LED lighting adoption, initial cost, according to Cree (Durham, N.C.).
Cree maintains that the XT-E LED more than doubles the lumens per watt (LPW) of its XLamp XP-E LED family—providing up to 148 LPW at 85°C (or up to 162 LPW at 25°C) at 350mA. The XT-E LED delivers exceptional performance in the 3.45mm x 3.45mm XP footprint and can be used for almost all lighting applications, according to Cree.
Because the XT-E White LED is a successor product to XP-E High Efficiency LED, customers who incorporate it into lighting systems require only 3,000 hours of XT–E LED LM-80 data to achieve Energy Star qualification, as opposed to the normal 6,000 hours, Cree said.
Mike Watson, Cree's senior director marketing for LED components, said through a statement that Cree's XB-D LED "changed the game," introducing a better price-performance curve. "Now, with the XT-E LED, Cree continues to break barriers and extend its leadership on this new trajectory, delivering products that accelerate LED adoption," Watson said.
The XT-E White LED delivers up to 148 lumens and 148 LPW in cool white (6000 K) or up to 114 lumens and 114 LPW in warm white (3000 K), both at 350 mA, 85°C, according to Cree. Samples of the product are available immediately and production volumes are available with standard lead times, Cree said. More information about the XT-E White LED is available on Cree's website.
The decision to go AC vs DC was made a long time ago. Of course, we would not go DC over the distribution network. However, we COULD have a low voltage supply and wire the light switches with a smaller guage wire, needing less robust switches. Perhaps a not trivial reduction in wiring costs, as copper has gone up dramatically.
We would still have the AC for appliances and such.
It would not be a big deal for new houses.
This would mean 2 types of bulbs- DC for new, AC for old. This could be a show stopper due to manufacturers probable unwillingness to have 2 types. But, if LED is the way of the future, why not use it as close to the "raw" state as possible? Cheaper for product, less manufacturing cost, less copper cost, less wiring installation cost. And, less high voltage AC in the walls
(BTW, I previously said DC for doorbell, incorrect. It is 12VAC, I think)
??? Wouldn't it be infinitely less disruptive (and I mean that pejoratively) to stick diodes in the CFL instead, if they prefer DC?
DC house current would mean that any appliance that doesn't require strictly 115 V would have to have a switching power supply. Not to mention, the electric utilities would have to co-locate gymongous rectifying circuits where they now have the final distribution transformers that go to 230 VAC. Which means, huge changes all over the distribution network.
Not a trivial change.
I have had somewhat the same results as DrQuine with CFL failures at home. In 2 years, I have replaces maybe 1/2 dozen bulbs out of the 30 or so that I have in service.
If one researches, it appears that the failures are due to the electronics associated with start-up.
In order to eliminate these issues, is there any effort to start wiring houses with DC for lighting? We already have DC for doorbells. This would be an easy extension, and would eliminate the cost of the start-up circuitry, and the associated failures.
We haven't anything remotely close to that. The CFL brands we buy are Sylvania or UtiliTech, which are sold at Best Buy. We've had much better luck than what you describe.
Basically, one failure that was premature, within maybe less than a year, one failure in a couple of years (which is also premature, in my book), and the rest keep soldiering on for many years.
As to going to laser lights, interesting concept. I wonder if the coherent nature of laser won't create some weird phenomena?
Our electric utility companies distributed many CFL bulbs for free, or at greatly reduced cost when they first came out. The fact that each CFL contains a small amount of mercury makes them much less desirable than LED's when you take into account the disposal cost.
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.