Given the cost of the bulbs, the savings can accrue over time but with the limited lifetimes (power electronics typically) I am not sure the bulbs will ever pay for themselves based on electrical usage. I do know that in a number of applications they are very nice - quick to start and energy efficient (more for the PR and customer experience than real savings). Some companies will want to jump on the bandwagon just for the green-ness of the bulbs, again maybe more PR than anything else.
I think they do pay for themselves even at the current prices. I replaced 3 50W halogen bulbs on my kitchen hood with 8W LED lamps which are brighter which means I can operate them at a lower dimmer setting. Bulbs were $20 each.
savings per year at 5hrs a day for 360 days at 11c per kWh = $7. so return is in 3 years approx.
This is conservative since we now keeps the main kitchen lights off most of the time since all we need is lights over the stove at least in the daytime. Earlier, we had to turn all the lights on for an extra 65W for 5x13W CFLs.
I don't think that SiC semiconductors are anything particularly new. And, according to
when applied to LEDs, SiC seminconductors are used to create blue LEDs. That yellow colored phosphor is what changes to light to white.
Here are the types of semicondictors used to create different colors, according to that URL:
"Silicon carbide (SiC),
indium gallium nitride (InGaN), and zinc selenide
(ZnSe) produce blue LEDís.
(GaP), and gallium nitride (GaN) produce green
"Gallium arsenide/phosphide (GaAsP) produce
red, orange and yellow LEDís.
arsenide (AlGaAs) produces red and infrared."
It goes on to say that white light can be made by combining red, green, and blue, although I'm pretty sure that's the more expensive way of making a white LED. The cheaper approach is just to use a blue plus a phosphor.
I think that having any new appliance that requires LESS power than what it replaces, for a change, can only be beneficial overall. That in itself is worth money.
Obviously, this can be taken to extremes, but it seems to me that it's wrong to dismiss these improvements, only on the basis that overall acquisition and operating costs are perhaps not quite low enough. Would anyone be so cost-obsessive, say, about their food? Never mind clothing?
Think of it this way. Flat panel TVs, especially plasmas, require considerably more power than the CRTs they replaced. Thank goodness we have LED lighting just around the corner that can actually compensate for this.
This is a good advancement. The move to LED lighting will happen once it is better (cheaper) than what is available. The price of LED bulbs will continue to come down as the volume increases and the advancements in the science continue. I look forward to moving to that technology.
The LEDs are supposed to have a life of 25 years. If the associated electronics also lasts that long then LEDs will become a good lifetime investment for lighting and saving a huge amount of energy cost over their lifetime
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