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LED Headlights in Audi Sports Car

It’s interesting to see that Audi is releasing a car with LEDs for all lights including the headlights. This is being promoted as an environmental benefit, however a quick google search revealed that my Volkswagen Passat apparently takes 55W headlights (giving a total of 110W of electricity used). Even allowing for some inefficiency in the alternator this would make a very small impact on the fuel use of a engine rated at 140KW. The Audi in question is the R8 (wikipedia link because the Audi web site is badly broken) and has a 300KW engine…

A simple implementation of LED headlights will do some good for plug-in hybrid cars and all-electric vehicles where saving power is more important – when the technology filters down to cheaper vehicles. Also one possible use for the technology is to dim the headlights by turning off some of the LEDs in the bank (according to the LED Wikipedia page it is currently impossible to create a single LED that takes more than 1W of power, so a bank of LEDs would be used). Currently you have a choice of using “parking lights” or “head-lights” when driving, and when driving just before sun-set or at night in the city (where the street lights are bright) you need head-lights to allow other drivers to clearly see you but don’t need them as bright as they have to be when driving at night in the country. So a range of levels of luminosity could be effectively used in headlights to increase efficiency in some situations and increase light levels in others.

According to the Luminous efficiency Wikipedia page current LEDs are up to three times as efficient as quartz halogen incandescent globes and future developments are likely to increase that to six times the efficiency. Combine that with more effective use of headlights to provide the light at the location and level that’s needed and the result could be using at little as 10% of the electricity for headlights on average!

Another thing that I would like to see is the Adaptive Headlights feature of the better BMWs (which I referenced in a previous post about the BM 5 and 7 series) implemented in a cheaper and more reliable manner. The feature in question is that the headlights will turn when driving around a corner to show the road ahead instead of just shining off the edge of the corner. Implementing such a feature with incandescent lights is difficult because they have to be physically turned and moving parts tend to break (which increases maintenance costs and decreases the overall reliability of the vehicle). An obvious alternate design is to have a set of LEDs pointing in different directions and which LEDs get power would determine where the light goes (this would also react faster than physically moving a light). Once LED headlights become common the Adaptive Headlights feature could be implemented in the cheapest cars on the road with minimal extra cost – currently it’s a feature that would be expensive to implement and would increase the sale price of a small car and probably the service price too.

7 comments to LED Headlights in Audi Sports Car

  • asdf

    this sounds like musik in the ears of the industry …

  • Peter Nelson

    Good to see the Citroën DS’ steerable headlights from 1967 coming back in fashion, I guess.

    One problem with ‘ultra bright’ LED brake lights is they often flicker. Try concentrating when everybody’s lights do the same.

  • The main advantage of LED over incandescent bulbs is their lifespan. Even if they don’t use as much power, which is still nice, the point is that you don’t have to replace them. And even if one LED in your bank happens to die (which is a rare event indeed), you can afford not to care, since you only lose one percent of your lighting power.

  • Jon KÃ¥re Hellan

    I’m fascinated to see a Green blogging about luxury cars. Myself, I’m a card carrying Conservative who commutes by bike. Do keeep them coming!

  • etbe

    Jon: My response was exactly the same when I first read a report about the LED headlights. But when the potential for the same technology to be used in cars like the Prius was pointed out to me the benefit became apparent.

    I am also strongly in favour of car safety, so anything that improves safety is a good thing even if it’s not so environmentally friendly (look at the amount of high-end safety gear that is in the standard Prius and how much extra is in the i-tech Prius).

    Most of the good stuff in cars starts at the high-end and gets installed in cheaper cars when technological development drives down the construction costs.

    PS You might want to check out the cars category for my post about the Mercedes S class.

  • Echoing Peter Netson’s comment, plus I think that the eerie “tracking” effect of the Citroen’s headlights is good value all by itself. (-:

    With a little practice, I was able to follow pedestrians around with a D-series’ lights (with some encouragement from the recently-deceased VPR) & found it to be quite enjoyable.

    I don’t know whether awareness of such features technically made me a better (more concentration) or a worse (more distractions) driver, but it certainly made the driving more interesting & pleasurable.

  • Carlos

    Hi.
    I want to install the Audi S6 front LEDs on my S4. I was wondering if you guy knew how much it would cost just the lights.
    If you can help me, please send me an e mail. austrayo18@hotmail.com
    Thanks!