I went looking for a small 40W incandescent appliance bulb for the fridge this morning and while the local hardware store did not have such a thing (the dollar store did, though) I saw something else of interest: A supposedly 40W equivalent LED "bulb" that uses only 1.5 Watts. And while the price was not as low as incandescent, or even CFL, it was about what CFLs were not all that long ago. I splurged and bought one.
Why buy a $10 bulb? Lifespan, heat, efficiency, and just plain curiosity. I'm expecting another CFL to fail in the office light fixture (four bulbs and a fan) and it's tiresome. Mainly because I have to store the defunct CFLs until sometime in October when the folks that deal with fluorescents are in town again. So now it's three CFLs and one LED bulb which has pre-emptively replaced a CFL, which is now a spare.
Here are my initial impressions:
The good: It works. If you like full instant-on, this does it. The light is diffuse enough that in a typical non-horizontal reflector fixture it doesn't seem like a spotlight. It runs relatively cool. The current limiter gets warm, but one can grasp the envelope and unscrew it even after it's been on for some time. I haven't noticed any flicker, something one might expect with AC-powered LEDs. No mercury. And hopefully a really long service life.
The bad: The price is a bit high. This isn't something I'd re-lamp the whole house with, at least not yet, but the next CFL that goes out in the office* will get replaced with LED. It looks like this would not be a good replacement for a horizontally mounted bulb. Also, 40 Watt is the highest wattage equivalency I've seen for sale in person yet. If there were a 100 Watt equivalent at about the same price, the kitchen light would likely be up for replacement. Also, there's no Energy Star logo on the packaging that the local electric service requires for a rebate of some of the cost, but then the rebate is (so far) only for CFL.
The... not ugly: The LED looks bluish when you look at it, even compared to the "natural white" CFLs which are certainly whiter or bluer than the "soft white" yellowish CFLs. The LED bulb doesn't seem as bright or perhaps just not as dazzling, but working under it doesn't seem dim or lacking at all. Checking back, it should seem dimmer as the CFLs are 60 Watt equivalent, not 40 Watt equivalent.
The bulb is a clear plastic globe envelope with 20 individual LEDs near the base. They appear to be indium phosphide with fluorescent powder. When switched off, the internal surface of the diodes glow for a while. The glow is enough to be seen, but not enough to really see by. In a desk lamp fixture, the bulb does not protrude from the reflector at all and even it did, the LEDs would not. Between that and the narrower beam width of LEDs the result is that the light doesn't flood as much of a room as the equivalent incandescent - I checked. The beam width isn't overly narrow, however. It's just more like what you might expect or hope for from a shield or reflector.
Before we converted away from incandescent, the office light fixture had four of them, at 40 Watts. That was 160 Watts total. The CFLs (60 W equivalent) use 13 Watts each, for a total of 52 Watts. The LED uses a mere 1.5, so
if when we convert the office fully to LED, the lighting will use all of 6 Watts - one Watt less than an incandescent nightlight.
* Or one like the ones in the office, then one in the office gets moved and replaced by LED.