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Screw-in LED Floodlights
Anonymous Coward writes "This company claims to have the first LED flood lights that you simply screw in as a replacement for your old bulb. enluxled.com are also claiming it's cool enough to handle, more damage resistant, longer lasting (50,000 hours) and only uses 22w to produce twice the light of a 100w bulb." And hideously expensive, but you never have to change them.
I live in the middle of an Amish community. I know that LED has been growing amongst them as a lighting source. An LED table lamp powered by batteries is becoming quite common replacing the hot, noisy and potentially dangerous gas lights that have been used in the past.
They come in 45 watt and 65 watt equivalent bulbs, not twice the output of a 100 watt bulb as stated in the article ;) At this moment a CF bulb can be more efficient than them, pulling as little as 14 watts to produce the same output they do at 22. Tubular fluorescent bulbs are even more efficient.
They do look cool though, and LED's get better and more efficient every year.
At a watt or 2 there is nothing that can touch an LED as far as efficiency, but as soon as you go to higher power levels then even a halogen bulb can be more efficient. In my 1AA flashlights nothing is better than an LED. Plugged into the wall you're better off with a CF bulb.
Reasons for using LED over Flourescent:
1) When a flourescent bulb fails, it stops giving off light completely. Usually and LED light will only have 1 led fail at a time. Given theis, you don't have large areas of darkness and don't have to replace the bulb immediatley when a part fails. LEDs fail gracefully.
2) LEDs are more resistant to damage.
3) The LEDs appear to not need to be replaced as often as Flourescent. The largest "Pain" in lighting is having to replace the bulbs. If these new LEDs last sufficiently longer than Flourescnets, they pay for themselves in labor.
4) I'm not sure about this, but I don't think I've seend flourescent spot lights before. However, the LEDs might be able to put out more light than flourescents.
Fly me to the moon Let me sing among those stars Let me see what spring is like On jupiter and mars
THIS IS NOT TRUE!!
The specs for the light are I beleive 300 lumens. This is more like a 45-60 watt bulb.
A 100 watt bulb might generate 1500+ lumens.
It still is significantly more efficient, and with a SIGNIFICANTLY longer life span, but it is not equal to a 100 watt bulb.
When these first came out (won some awards) I checked them out for this very thing.
They also are not an all around type light a la a lightbulb, more of a spotlight (90 degree beam angle?), so better for flooding a wall or artwork with color / light.
Still super cool. Still a bit expensive.
How does this compare to...Energy saving bulbs we have today?
Power usage for a given amount of light is slightly better (22 vs 26 watts for a 100 watt equivalent).
Life is a lot better. (50,000 hours vs. 6,000, or about 8 1/3 compact fluorescents to match rated lives with one LED lamp.)
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Traffic lights, for example, are owned by a city. The city keeps accurate budget information about how its money is spent. Incandescent traffice lights are typically changed on a yearly basis and require a substantial workforce with trucks and ladders to reach the bulbs. One can usually make a convincing case to a city that using LED traffice lights will save $x per year, and so the city opts to use LED lights.
I personally do not keep track of my light bulb spending, and I imagine most households also do not. Thus the "it saves money in the long run" is a much more difficult argument to make.
Furthermore, making white LEDs is typically done either with a blue LED surrounded by something that will emit yellow (and transmit some of the blue) when the blue LED is lit, or by using a red, green, and blue LED together.
The first style has makes a white light that isn't "nice", because it's creating "white" by only combining two colors in the spectrum (blue and yellow). I can't explain it more than that, perhaps someone more knowledgeable can? This style is great for outdoor lighting (street lamps) where "niceness" doesn't matter so much; people aren't trying to read a newspaper but are merely identifying oncoming traffic.
The second style is great (well, as good as RGB monitors), except for one problem: the different colored LEDs wear out at different rates. Thus the color of the light will drift slowly over time and obtain a green hue (how much time? I don't know... 2 years? 5 years?). So, the LEDs may last forever, but the "whiteness" may not last much longer than a conventional bulb.
An aside: what is really cool about the tri-color LEDs is that you could potentially have dials to adjust the relative intensity of the colors and thus produce any color of the rainbow (or RGB spectrum at least), leading to many decorative and even utilitarian applications (e.g. a light inside a water faucet that lights the water according to its temperature).
It's been a while, but I think most of the numbers are still correct;
Lumens/Watt Light Source
100-190 low pressure Sodium (HID)
(150 90W low pressure sodium lamp, clear)
50-150 High pressure Sodium (HID)
(115 1000W dual arc-tube high pressure sodium lamp, clear)
100 Sylvania 18 watt low pressure sodium
84 32W, 48" MOL, T8 OCTRON fluorescent lamp,
60-65 standard F40T12 cool white fluorescent
64 250W mogul based metal halide lamp, clear
60 150W single ended compact metal halide lamp
48-60 compact fluorescents
45-55 Super bright Red/Orange LED
35-45 Super bright Green LED
17.5 Tungsten Halogen Single-End SUPER-Q Frosted Finish D.C. Bay 100Watt
17.5 100W Incandescent A19 Bulb, softwhite
14.5 60W Incandescent A19 Bulb, softwhite (standard bulb)
6 incandescent night light bulb (7w)
6w incandescent flashlight bulbs
For normal home lighting T8 fluorescents are probably your best bet today.
LEDs are good when you're want colored light, when you want a small amount of light, or when the cost/hassle of replacing the bulb is the major factor.
Cree recently announced a 75 lumens per watt white LED, but AFAIK they aren't available in quantity yet.
There's a lot of hope for the future of LEDs, but they're still a few years off.
-- should you believe authority without question?
Let's bring a bit more factuality to the situation: The parent poster states that heat pumps are cool technology, and that radiant electrical (resistive strip) heating is inefficient.
Guess what? Parent is correct.
Radiant (resistive strip) heating is LESS efficient than a heat pump under many circumstances. "What? No, stupid - radiant strips are 100% efficient! All the power is converted directly to heat!" Yes, it is - but I'm not stupid. Heat pumps are more efficient. Typically, with an outdoor temp of 45F an an indoor temp of 72F, the heat pump moves THREE TIMES as much heat into your fine home as it requires electricity to perform the pumping. IOW, 100W of energy into the heat pump results in 300W of heat into the house. That's three times more efficient than strip heating.
This is not as pronounced at greater temp differentials, and in fact many heat pumps employ supplementary strip heating for really large temp extremes. However, the parent poster's point is well-made and accurate - radiant strip heating IS, in general, less efficient than a heat pump.
I live in Florida - north Florida. It's November 21, and my A/C is on. Every watt I save from running fluourescent or LED lighting is effectively 1.3 to 1.5 watts less electricity used and charged on my power bill. A similar argument can be made for a house using a good heat pump - the extra wattage radiated as heat by an incandescent bulb would provide even more heat if it were used to drive a heat pump instead.
Ce n'est pas un vrai mouvement de robot!