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Discussion Starter #1 (Edited)
Has anyone spent a lot of time researching or trying out different interior and exterior lights to find the lowest power lighting options.

I'm ready to start looking as LEDs, but I wonder if there is not a lower power solution?

Well this has been easier than I thought....

In general LED lights use 1/10 the power and produce about 50% of the lumens.
All LEDs are easy to find except the head lights...lack of lumens might be the reason.

I'll post my spreadsheet for Fiero Lights to LEDs tomorrow.

Not cheap but a quick and easy way to cut down on power usage.

Very open to any other ideas.
 

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I'm ready to start looking as LEDs, but I wonder if there is not a lower power solution?

Very open to any other ideas.
LEDs are suitable for sidelights, daytime running lights, indicators, brake lights, reversing lights, dashboard illumination and interior lights. You could try some Luxeon Rebels for high brightness lights, but they're not really suitable for driving lights. For low-power, high intensity driving lights, the current trend is switching from incandescent to HID lights. eBay typically has HID kits for most, if not all, vehicles out there.
 

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Has anyone spent a lot of time researching or trying out different interior and exterior lights to find the lowest power lighting options.

All LEDs are easy to find except the head lights...lack of lumens might be the reason.
The low luminosity isn't the real issue it's heat. Yes, LEDs are 10X more efficient than incandescent, but semiconductors (especially surface mount) aren't very good at getting rid of heat. Not a problem for low wattage indicator lights. However, headlamps would need some major airflow and/or other cooling apparatus to dissipate watts needed for headlamps to make them last. Check out the huge cooling fins on current LED substitute lights for 100W household lights.:eek:

HID at 35W vs. the normal 55W-60W headlamp is a reasonable energy savings. Shop around - some HID conversions are quite expensive (multi-$100), but there there are some less expensive options available.
 

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In general LED lights use 1/10 the power and produce about 50% of the lumens.
And all the lights you need in a car consumes just a fraction of the power the motor needs.

I'm not saying that replacing lamps with LED won't conserve energy, but you can probably affect range much more by keeping the brakes in top shape, repacking bearings, reducing wind resistance, keeping the batteries warm if you live in a cold climate etc...
 

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Discussion Starter #5
True but my Aux Batt won't touch my traction batts.
Aux will only be charged via solar... So I want to keep this power consumption as low as possible.

Not designing this for long range so it probably won't matter but might as well make all improvements while I have everything apart.



And all the lights you need in a car consumes just a fraction of the power the motor needs.

I'm not saying that replacing lamps with LED won't conserve energy, but you can probably affect range much more by keeping the brakes in top shape, repacking bearings, reducing wind resistance, keeping the batteries warm if you live in a cold climate etc...
 

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The low luminosity isn't the real issue it's heat. Yes, LEDs are 10X more efficient than incandescent, but semiconductors (especially surface mount) aren't very good at getting rid of heat. Not a problem for low wattage indicator lights. However, headlamps would need some major airflow and/or other cooling apparatus to dissipate watts needed for headlamps to make them last. Check out the huge cooling fins on current LED substitute lights for 100W household lights.:eek:

HID at 35W vs. the normal 55W-60W headlamp is a reasonable energy savings. Shop around - some HID conversions are quite expensive (multi-$100), but there there are some less expensive options available.

no. the fins you mention are for the transformer and other circuitry to covert 120 AC to the appropriate DC voltage and amperage.
 

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Discussion Starter #7
no. the fins you mention are for the transformer and other circuitry to covert 120 AC to the appropriate DC voltage and amperage.
I assumed this as well.. I've not taken a 120 AC LED bulb apart yet. They are higher efficiency meaning the convert more power to light and waste less as heat.

Also there is no PCB area to dissipate the heat in a 120 AC outlet. I've dissipated a lot more than 10 Watts into a multi-layered board, but then again I had a lot of surface area to work with.

From looking over some bright LED specs I noticed they generate less lumans at higher temps.
 

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Discussion Starter #8
but semiconductors (especially surface mount) aren't very good at getting rid of heat.
BTW I am pretty sure this is not correct... I use to design a lot of surface mount D2Ds... A surface mount device with the correct package can dissipate a lot more heat into the board then a thru-hole mount. Heck even a SOT23 with it little legs can transfer a good amount of heat. But there are lots of packages that can do this.

If you are worried about dissipating a lot of heat out both sides of the board... just sink a lot of vias.
 

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Discussion Starter #9 (Edited)
Quick update

1) bright LEDs are very sensitive to temp and degrade rapidly over 20 C. That is another reason for the heat sinks.

2) Think I have found a nice LED or two for front head lights. Need to do a little more research before buying a few but these to look very promising.

a) First one is over kill between 3k and 5K lumen @ 24 V and ~ 1 Amp
http://www.bridgelux.com/assets/files/Bridgelux_RS_Array_Data_Sheet.pdf
About $60/each from Digi-Key. @ close to 2" think these could be worked into a traditional head light housing.

b) Second one is ~12V 880 lumens.. seen in lower right corner of this catelog
http://media.digikey.com/pdf/New Cat Page/US2011/Bridgelux/LED_Arrays.pdf

FYI: If you are not familiar, Digi-key is an expensive source, but a great place to find parts for the hobbyist.


Update: I went ahead and ordered the 880 lumen lights (digi-key part number 976-1028-ND. Also ordered to different reflectors. digi-key part number 711-1082-ND and 711-1083-ND).
Normal current of 1.2 Amps at 13V = 15.6 Watts for 880 lumens not bad.
The regular Fiero head lights are 9004's, 45 Watts and around 760 lumens. About 2.88 x less power and a little (16%) brighter.

Can't wait to get these in and give them a try....
 
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