Article: Hella LED Headlamp Study
 

Stumbled upon this article today about LED headlight technology from Hella.

The full article and pictures can be found HERE.


I'm excited by this report because it's showing an interest in viably offering LED headlamps in entry level cars and not just on the High end vehicles.

Using LEDs for every source of light in a vehicle would be able to help increase FE via reduced engine drag from the alternator under electrical load.

Just think if we could get retrofit units for older vehicles, especially ones that don't have power windows or locks. The electrical loads could be greatly reduced on a vehicle since the wattage from lighting would be virtually cut in half. That would mean that the big wattage drains would be from stereo and climate control fans then (excluding power windows and locks). Both the stereo and climate control fans (along with the defroster) could be manually shut off to relieve electrical loads. The ignition system would be one of the harder systems to change the electrical demand on though.

It would definitely help on my mileage. I lose about 2.5 mpg by just having the lights on and I can notice the added alternator load when climbing the mountain up to the NC state line.

I'd imagine that your car is getting down to the point where electrical load is holding you back Mike.

The big setback I can foresee would be price of the headlight units since it's supposed to be using "cutting edge" LED technology. Just like when the LED traffic lights first came out, the cost was almost 10 times the price, but the life expectancy on a unit was more than ten times as long as the incandescent version.

Say Mike - I forgot to ask: Your re-vamped tail/brake lights....are they LED units on the Aerocivic? I know that you could replace all the interior lighting with LED units as well as the OEM brake/turn signals. That way, the big electric drain would only be from the ignition and the headlights.

Too bad the article doesn't give any energy use figures for the same light output compared to halogen.

Anyone know the Lumen number on a head light?
I'm tempted to try out some of these 800 lumen/20watt LED's for my Citicar head lights, and I wonder if useing the frame at the heat sink would work, it's a big chunk of aluminum after all.

Looks like they're getting 20Watts for 800 Lumens and 50Watts for 1700Lumens

http://images.worldcarfans.com/artic...005.Mini3L.jpg

I know that the headlight bulbs that were in my Civic were 55Watts and seemed like only 1000Lumens or less of light, I stepped up to 100Watt bulbs and got maybe 1.5 times brighter, so maybe around 1500Lumens or less out of the bulbs.

Compared to ~1500Lumens @ 100Watts for a filament bulb as compared to 1700Lumens @ 50Watts, it's a good trade off. The only problem would be stepping up the Voltage since the 1700Lumen LED ran on 18-20Volts. It's not too difficult to do so really though, it's just that at nearly $100 per LED array and fabrication time, the LED alternative is quite pricey. :eek:

I might just go with those 800 lumen LEDs then for my citicar if I can get a converter box that will drop the voltage down from the cars 48v battery, and I would be really worried about how bright they are with a 40mph top speed and the car being mostly used in town, and there are street lights most places.
the real draw back is that unlike an incondecent bulb that radiates heat with it's light, the LED produces most of it's heat inside the chip, so a heat sink really is needed, altho this could be a good place for a heat pipe, and i planed out well that heat could be used for things like defrosting your windows!

I work nights (3p -1a).
I use a flashlight often.
I just got a light that uses led tech and is brighter than my older three c cell MagLight.
It faces the led rearward into a highly polished parabolic reflector.
Perhaps you can do that with these LEDs?
Just a thought.
S.

Most of the tail/brake lights are currently incandescent, but I plan to replace the tail light bulbs with LED's, I'm not going to bother LED'ing the brake and turn signal lights since they are so seldom in use. Also plan the replace the dash and dome lights with LED's if I can find them.

I have some LED mag lights, both Mag brand, and Kree, and they are amazing, longer battery life, and much brighter, I can put a clear bright spot of light on stuff over a block away, and can still see the light a quarter mile away, it's the the point were I don't under stand why they still sell krypton bulbs.
I also have a Nite Eyes brand LED, and a home made 3LED cluster from about 8 years ago when white LEDs first came out, both of those are still brighter then the stock mag bulb, but not by much, I think the nite eyes LED is currently in an old crome plated brass flashlight and it's kind of fun, very shiny with pure white light.

Autospeed article on building LED headlight.
http://autospeed.com/cms/A_109714/article.html

Can't you just mod your existing headlamps to use LEDs instead of regular ones? I would think all you would need to do would be to add a resistor or two to the line to lower the voltage a little bit and then pop in between 10 and 20 ultra bright LEDs in each lamp fixture to make it work...seems like it would be simple enough in theory. Then in the back I would wire up a string of LEDs that ran along my bumper as night time rear lights, that way only the break lights are using the regular lamps.

Gotta love instructables.com
http://www.instructables.com/id/DIY-...r-headlights!/

those LED's don't sound so good any more, I just checked the lable on a new 13 watt CF, and it's rated at 800 lumens, so those 800 lumen 20 watt LED's are sounding less great only 40 lumens per watt insted of 61, if only CF bulbs fit in head lights.
found a few more:
50 watt LED (wow) but it's only 1,700 lumens, only 34 lumens per watt.
3 watt, 80 lumen around 26 lumens per watt, and that seems to be pretty standared for something that can run for more then just a minute or two.
but this is the best I've found! 1.3 to 3.7 watt, 107 to 228 lumens (depending on how you regulate them) $9 each $8 if you buy 3 or more, but it also needs a driver that is going to regulate the voltage very carfully to keep it from burning up, but I think if 5 or more of those were mounted in a reflector, with good heat sinks (still like the heat pipe chanaling heat to defrost the windsheild) and had them at full driven power for high beams, and I like them because they give you specs over a wide range of amps going thru them, and if you don't need them as bright they are more efficent!
as for tail lights, I already use LED tail lights, they are brighter and use less power then standard bulbs, I personaly tested them at less then 3 watts each.

hmm i have been considering doing led headlights for a while and think i may get some of those 800 watt "bulbs" sounds like a fun project

I would first try leds as DRL's, sort of a compromise where you can run them on just with the parking lights not consuming a lot of power. In addition depending on the car model, you can remove the drl/marker light and leave the headlight intact, so you have no downtime and don't have to do a rush job in a daily driver. If you get enough brightness in the second housing, you can probably use them solo at night in traffic and only need the real headlights on a dim road.

I too have upgraded led flashlights. One thing ive noticed is you can buy 99 cent store C/D-cells and they'll live forever. The savings are very notable. I have a 3 year old.