Plug
Posts: 259
Joined: Fri Aug 02, 2013 1:17 pm
Location: UK

Adaptive LED headlights

Mon Aug 19, 2013 11:07 pm

I'm close to deciding on my final spec now and should be popping in to my local dealer to place the order later this week. One thing I'm yet to decide on is whether to tick the Adaptive LED Headlights option and I've got a couple of questions,

1. Do LED headlights offer any significant range advantage over the standard lights or is it negligable ? I know this is a hard question to answer but is anyone able to estimate what the difference in range would be if you drove from full charge to zero with the lights on for the two options ?

2. What does the 'Adaptive' bit actually mean ? I presumed just turning into corners (which I'm not that bothered about). If you try google it there is an interesting video on the new adaptive LED lights for the 7 series which are very trick indeed but I'm guessing the i3 LEDs don't do this ?

http://youtu.be/-dvPZ3H1Vm4

AndrewDebbie
Posts: 171
Joined: Sun Aug 04, 2013 10:37 am
Location: Anglesey, Wales, UK

Re: Adaptive LED headlights

Wed Aug 21, 2013 3:30 am

Plug wrote:
1. Do LED headlights offer any significant range advantage over the standard lights or is it negligable ? I know this is a hard question to answer but is anyone able to estimate what the difference in range would be if you drove from full charge to zero with the lights on for the two options ?
I'll take a stab at it.

A standard H7 low beam headlight bulb is 55W. 110W for two. The LED headlamps on Leaf draw 50W for two on low beam. I'm also going to assume the non-led version doesn't use LEDs for any of the front lights. The rears are always LED. Assume LEDs there save another 10W

So the LED headlamp option saves about 70W. Low voltage power for the headlights comes from a DC to DC converter. For this very rough estimate, lets assume that the DC-DC converter operates at 93% efficiency. The real one might be a little better.

Total power savings from the Pack is 75W.


Assume you drive the car for three hours with the lights on and that uses up the entire range. 75W * 3 hours is 225W hours. The usable portion of the battery pack is 18,500 W-hours. Range difference is about 1.2% or about one mile of real range.


If the high beams are LED (they aren't on LEAF) power savings on high beam is about double. The car is probably driving faster so they won't be on for as long. Perhaps 2 hours at the most. Real range difference will be close to the same.
2014 LEAF 24 (gone)
2017 LEAF 30 (gone)
2018 Mazda 2 (Debbie's)
2018 i3s 94Ah Rex

Plug
Posts: 259
Joined: Fri Aug 02, 2013 1:17 pm
Location: UK

Re: Adaptive LED headlights

Wed Aug 21, 2013 4:00 am

Good answer. Thanks a lot for taking the time to go through the numbers.

I asked my local dealer about the 'adaptive' features and he wasn't too sure so I've ping'd BMW an email. I'll post again if I get any useful info back.

lordelectric
Posts: 5
Joined: Mon Aug 12, 2013 5:40 pm

Re: Adaptive LED headlights

Wed Aug 21, 2013 8:47 am

Plug wrote:I'm close to deciding on my final spec now and should be popping in to my local dealer to place the order later this week. One thing I'm yet to decide on is whether to tick the Adaptive LED Headlights option and I've got a couple of questions,

1. Do LED headlights offer any significant range advantage over the standard lights or is it negligable ? I know this is a hard question to answer but is anyone able to estimate what the difference in range would be if you drove from full charge to zero with the lights on for the two options ?

2. What does the 'Adaptive' bit actually mean ? I presumed just turning into corners (which I'm not that bothered about). If you try google it there is an interesting video on the new adaptive LED lights for the 7 series which are very trick indeed but I'm guessing the i3 LEDs don't do this ?

http://youtu.be/-dvPZ3H1Vm4
My opinion get the LED headlights for the i3.
I drove the Leaf before, turning on the fog lamps eats roughly 0.1kw per hr.
You can see an immediate increase on consumption on the display.
Which is why Nissan gave every Leaf LED headlights initially.
Again for most Prius and Lexus hybrids LED headlights are available.

Pt
- Less energy consumption - for each hr of driving in the i3 with non LED headlights on, expect to lose an extra km.
- LED headlights are whiter and illuminate better.
- It should hv be standard on the i3.

My numbers are not too scientific ... but are my actual observations from driving the Leaf.
Hope it helps.
2012 Nissan Leaf
2011 Lexus CT200h
2008 Prius

Plug
Posts: 259
Joined: Fri Aug 02, 2013 1:17 pm
Location: UK

Re: Adaptive LED headlights

Wed Aug 21, 2013 12:55 pm

lordelectric wrote:Hope it helps.
Yes thanks, there's plenty of us who've never owned an EV before so always good to get the opinion/experience of those who have.

Plug
Posts: 259
Joined: Fri Aug 02, 2013 1:17 pm
Location: UK

Re: Adaptive LED headlights

Thu Aug 22, 2013 11:49 pm

Reply from BMW said....
For the option 5A2, Adaptive LED Headlights, the LED lights improve visibility by following steering angle of the front wheels, giving better illumination ahead of the road through corners. The Adaptive headlights are not active when the car is reversing or when the car is stationary and turned to the offside, to avoid dazzling oncoming traffic.

i3andi8
Posts: 3
Joined: Fri Aug 30, 2013 11:33 pm

Re: Adaptive LED headlights

Sat Aug 31, 2013 1:30 am

The adaptive lights would be quite useful if you do a lot of nighttime driving and in darker roads. Where I live, there aren't too many street lights going up the canyon, so these road conditions. Especially if you have wildlife such as deers roaming.

ecoangel
Posts: 203
Joined: Sat Sep 07, 2013 2:50 am
Contact: Website

Re: Adaptive LED headlights

Sat Sep 07, 2013 4:36 am

How do the beams move? With electric motors? So there's more consumption
http://www.fuelly.com/driver/ecoangel/a2
http://www.fuelly.com/driver/ecoangel/a3

Parker
Posts: 334
Joined: Fri Jan 04, 2013 8:45 am
Location: UK, EU

Re: Adaptive LED headlights

Sat Sep 07, 2013 8:40 am

ecoangel wrote:How do the beams move? With electric motors? So there's more consumption
I'm not sure if the i3 is the same as other LED headlamps as I can't find anywhere where it mentions how many LED's the i3 lights use. But normally say there are 7 LED's they are arranged in such a way that when all 7 are on that is Max beam pattern and if something is detected in the road ahead then LED's are switched off so bits of beam are extinguished..... so there aren't any moving parts and the shape of the beam can react very quickly. They can use inputs from all sorts of different sources such as the adaptive cruise control radar and Sat Nav ..... even Google earth!

Atommad
Posts: 76
Joined: Wed Aug 21, 2013 2:38 pm
Location: NW UK

Re: Adaptive LED headlights

Sun Sep 08, 2013 10:22 am

ecoangel wrote:How do the beams move? With electric motors? So there's more consumption
One of the promotional videos shows the light move within the housing.

But more consumption? Well theoretically yes, but come on, you're not serious? :D

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