Can LED Headlights Increase EV Range?

While I was installing a set of LED headlights to replace the 20+ year old halogen headlights in my Ford Ranger Electric, I thought I would discuss just how much range an EV can gain by using LED instead of halogen headlights. The numbers might surprise some people, especially given the overall difference in energy consumed by LED versus halogen headlights.
spoiler It's not much.
The original halogen headlights in the Ranger EV would pull about 60 watts each, while the replacement LED headlights pull about half that. At a constant 45 mph, the Ranger EV will consume about 250 Wh/mi, so after an hour of driving, it will have drawn about 11.25 kWh. If these LEDs pull half the wattage of the halogen bulbs, after that same hour, they will have saved 60 Wh. So the overall difference in consumption will be 11.19 kWh to travel 45 miles, or 248.7 Wh/mi. Basically, the energy consumption difference will be a rounding error.

[@Chris-bg8mk]

One thing I wish you had covered was lenses and reflectors. The direction that the bulb emits light works integrally with the lenses and reflectors. Before I had my Bolt, I had a spark EV, and it came with an HID conversion. That was absolutely awful. I switched it to LEDs and it was still awful. Eventually, after tinkering a lot, switched it back to the stock, halogen bulbs, and all was good again. This was down to the way the light was emitted from the HID bulbs, and the flat chip on board LEDs, versus the somewhat more omnidirectional light emissions of the halogen bulbs that it was originally designed for. Food for thought. Love your videos keep them coming.😊

[@newscoulomb3705]

Thanks! I want to actually get them integrated and use them before I commented more. I've seen a lot of reviews with vastly different results depending on which LED was used (some are real stinkers), so I might not end up sticking with these. I also forgot to mention the other big advantage with LEDs, which is service life. Halogen are measured in hundreds of hours, while LEDs are measured in tens of thousands of hours.

[@maximaalski]

Thanks now I will stick to the default lights on my Bolt EV 😊

[@georgepelton5645]

Eric, Good Luck with your project. When you are done, it would be interesting to see a video summarizing the items you had to fix or replace to get this Ranger EV running again. BTW, good analysis of the magnitude of LED energy savings.

[@W4rH4wkXX]

i can barely see anything at night when i drive a car that has the stock halogen bulbs.... i was shocked how good the HID bulbs were in the 2017 bolt... other than the light color i have zero complains about the HIDs.... i've replaced all of my halogen bulbs in my other cars with LED 6000k-ish color .... sssssssoooooo much better and i can actually see the road 👀

[@ouch1011]

Another way to look at this, assuming the drivetrain is drawing about 9.5kW to drive the vehicle down the road at 45mph (I think that’s what your spreadsheet said), 9.5kW is roughly equivalent to the power draw of 316 of those LED light bulbs (assuming it draws 30w). So, the headlights are really an insignificant draw compared to the drivetrain and the battery size. In addition to that, _most_ people don’t drive with their headlights on at full brightness all the time, so the tiny power savings will only come into play when the headlights are on. Even cars with incandescent daytime running lights typically either use a lower wattage bulb for that purpose or dim the bulb to reduce the power draw. Regarding the headlights themselves, I’m firmly against putting any sort of brighter bulb into a reflector headlight housing designed for incandescent bulbs. It basically always results in offensive, blinding glare. If you’re going to upgrade your headlights, do it properly or leave them alone. Most of the LED bulbs designed to fit in place of halogen bulbs are absolute garbage and the very few out there that can actually work decently in a reflector housing cost $150+. For $45 I can basically guarantee you bought garbage that will blind oncoming drivers and probably put less light on the road than the stock halogen bulbs.

[@newscoulomb3705]

Yes, headlight patterns are something I'm very sensitive to. Even the Bolt EV's stock headlights bother me for that reason (they send a small beam of light into the opposite lane). The LEDs I brought are designed to mimic the halogen filaments and work specifically with this reflector housing, so if installed properly, they should have a very similar beam pattern (though different and more light overall).

[@daves1646]

LED bulb replacements. Increased illumination is worth it, AS LONG AS ….. Focus and Distribution of light is EVERYTHING. There’s a LOT of LED bulb kits that have horrible light output patterns, not limited to poor vertical cutoffs letting light glare upward (into oncoming drivers) AND poor focus of light onto roadway forward. Best to see examples of output pattern from the vehicle headlight or, at least, KNOW the LEDs are centered and at same distance as standard bulb filament from the reflectors.

[@newscoulomb3705]

Yes, that's the reason I got this bulb specifically. The LEDs are in identical position to the halogen filaments, so the light pattern should be identical. There's still margin for error, of course, but these are supposed to be one of the best at maintaining the original reflector headlight's pattern.

[@ab-tf5fl]

Another way to illustrate the math: the two halogen headlights use a combine 120 watts. According to Google, a beginner cyclist can put around 75-100 watts of power into the bike from their own muscles. The difference between halogen headlights vs. LED headlights (60 watts) is less than this. So the added range you get from switching the headlights is roughly equivalent to transferring energy into the truck battery from the driver's leg muscles by way of a pedal-powered generator. And it does not take a rocket scientist to realize that energy from human pedal power is essentially meaningless when it comes to moving at speed something as large as a small truck. The only way human pedal power (and also headlight efficiency) really matters is when the vehicle reaches the efficiency of an electric bicycle, something which even an Aptera comes nowhere close to.

[@usaverageguy]

An illuminating video.

[@mikehedrick6544]

Yes, and with a bright side.

[@rp9674]

Apparently headlights aren't on a canbus system. Canbus messes it up for all the other LED applications. Using a load resistor undermines the point of saving power

[@newscoulomb3705]

The power draw numbers should include the resistor. They do for 120 V socket LEDs. If it losses from the ballast resistor are in addition to energy consumption of the LEDs, then yes, that impacts the energy savings. At that point, it would be back to double the light/visibility for the same power.