The 55W and 100W are easier to do, I just need to stick/screw them to a good heatsink (PC/CPU type works fine). For the 500W I will be buying a high power 24VDC power supply for testing and development (1500Watts). Once I get there I will be taking pictures and video. I really do have to water cool the 500Watt LED, otherwise the 500Watt heatsink is 12" x 14" x 8" thick, and needs two 120mm fans moving 200+ CFM each.
We are also moving this week (we believe) so work will be slow but still happening (need something to do to keep me sane in the wee hours).
Yeah from what I read, a 35Watt automotive HID is about 2900 lumens new, a 55Watt is 4500 lumens new and a 100watt is about 8000 lumens new. The general energy efficiency of HID is about 80 lumens/watt for the automotive type. You can get higher, but the cost goes up and the Chinese don't copy them as well. I'm also staying away from HID conversions on this project since I want full DOT compliance. There are DOT compliant HID conversions, but I'm not familiar with a 55Watt version being compliant.
I'm not judging, I have 35Watt high/low HID aftermarkets in my Toyota Pickup in Cibie ECE housings, but I know I'm not compliant and won't throw a fit if a LEO catches me on it. And some guys think that the color temperature above 6500K is better (I've seen some here in the S.F. Bay Area that look purple) - I'm not in that camp, I run 4300K HID which is somewhere between daylight and incandescent light (a reasonable target window for "white" IMHO).
This issue with DOT regulations is also why I'm not putting these in the headlights - they are for Aux lights, and will be locked out for normal road driving. The LED headlights will be commercial-off-the-shelf J. W. Speaker 8900 Evolution fixtures.
Power white LEDs are anywhere from 50-120 lumens/watt right now, the LEDs I picked are in the 105-110 lumen/watt range with 4300K white, and Chinese for cost. One of the nice things dealing with the Chinese on LEDs is that they remember that I'm the customer, so they give me what I want and ask for (i.e. color temperature, connection topology, power, etc...). I've only found one US LED company that was this accommodating recently, and it was the LED company that sold me the NVIS Green A parts -
Wamco (BTW this is NOT a paid or otherwise compensated recommendation/endorsement, this is my experience on this project and topic I paid for my parts without any request or expectation of endorsement).
The other thing for me was the life - a halogen you get about 1000-2000 hours out of, an HID you get 5000-9000 hours out of, but with an LED you get 50,000-75,000 hours out of before it gets too dim if you drive it correctly - and unlike an HID it doesn't usually take the power supply (ballast) out with it.
[Edit:] For giggles, I'm going to ask the LED company to build me a 32x32 die arrangement LED, which will give me about a 1150Watt LED @ 127,000 lumens with 102 volt drive and 11.25 amps. Just trying to push the technical envelope - four of them would make a great scene light on a mast. This probably won't go on the truck though - separate endeavor of potential interest. [/Edit]