If you’ve been reading my ramblings for awhile, you know I’m really into LED lighting technology. Why?
- LEDs are extremely durable because they are solid state “radiating matter”, no fragile filaments or ballasts
- many options exist for light patterns, as opposed to an HID where the lens/reflector/light are a one piece deal. this allows you to put the light where you want it, lowering the overall luminosity requirement for an application.
- LEDs produce vivid, white light that is especially nice in green underbrush, but works great everywhere I’ve had it so far.
- very lightweight, minimal material requirements.
- LED technology is advancing at a rapid rate while halogen and HID are sittin’ still.
- instant on/off compared to the HID slow ignition.
Putting my $ where my mouth is, I’ve used my homebrew lights this year every time I raced in the dark. For KTR, I used a 2 x luxIII helmet mount (and batteries were on the helmet too). It proved to be great lighting for the conditions. In Steamboat & the first leg of the E100 I used a similar system, and in the Koko record ride and Moab 24 I used my newer K2 lights.
The K2 lights are sick and I’m convinced were the brightest thing going at Moab. They are a LOT brighter than my Niterider HID. That’s a strong statement, considering that by the stats the HID should have been roughly twice as bright – it puts out 2x the lumens. But, luminosity is only part of the story. The color of the light matters, and where it goes matters even more. The Niterider HID pattern is quite wide, so all those lumens end up in places I don’t look. But…I designed the K2 model to put the light where I wanted it, and presto – the death ray is born!
Now let’s consider efficiency. For each watt of power consumed, how many lumens are produced? HID technology has had a stronghold in this arena as far as bicycle lighting is concerned with a typical efficiency of 50-60 lm/w (halogen I think is in the 15 lm/w ballpark). The K2 LED falls somewhere between 25 and 45 lm/w, depending on the current. They (like all LEDs) become less efficient at higher currents.
Enter the Cree XR-E LED. Cree has been supplying cell phone manufacturers with blue LEDs for some time. A relatively new company, they were initially immune to the ups and downs of cell phone sales. But in the past 4 years they have saturated the cell phone backlight market so have been busy looking at other lighting possibilities. Flourescent lighting is very efficient at 70-100 lm/w…but that’s where they want to go. Their new XR-E LED puts out more light than any other commercial LED and is more efficient than any bright LED at 70 lm/w. They are moving at a fast clip too – they’ve got LEDs in R&D right now that are producing 131 lm/w and expect to have a commercial product in ’07 that puts out in excess of 100 lm/w. That’s nearly twice as efficient as HID, and given all the advantages to LED lights…
Just like that, HID technology is so yesterday.
A couple more great things about LEDs: they are plenty bright and most efficient at lower power consumptions. HIDs are not – you gotta run at least 12 W, period. This enables enormous control over runtime capabilities and hence battery requirements…which means these babies are perfect for ultra stuff as well as NASCAR style 24’s. As efficiency increases, we’ll either have lighter batteries or more runtime – or both. It’s only gonna get better for quite some time.
So here’s the deal. While my bones are knitting I need something to think about. I’m after the perfect light design and have a lot of ideas, but if you could share your lighting requirements, especially where ultra events are concerned, that will help steer/form a good design. I think with some swappable parts a single system could work for just about any application…what would you want for your lighting application?
You can put your ideas in the comments section (which requires that you register to the site), or hit me via email at hairball.dh @ gmail.com.
We are not mushrooms…