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So delighted that I can open the front an/or back windows at road speeds with no buffeting! I realized that I was driving 50 with the windows still down an inch or two from parking and started to grin. I played with them at various speeds and could only get a small amount of discomfort with only back passenger barely open while running AC and fan at max. Yes, most of the time I will still use just AC, but I love knowing I have a choice of putting my windows down!
 

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There are certain combinations of window openings that can cause those unpleasant standing waves but this car is not as extreme as many cars.

It takes really hot weather for me to use AC so I have my windows open a lot. The thing for me is to optimize the ventilation and keeping the noise level as low as possible. Even after a year of ownership, this still takes some experimentation with how much to crack each windo - I'm assuming because of outside wind direction and magnitude.
 

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I have a different take on this.



Having a window open will affect the aerodynamics of the car. If you have air circulating into the car while driving then you will be changing the drag coefficient as air is now taking a different path. This will affect the efficiency that the car will drive at.


In a gasoline-only car, the A/C unit pulls power away from the engine to drive a compressor. This reduction in HP results in the engine requiring to rev higher to produce additional power and in turn uses up more fuel. However, the NIRO does not have the A/C running on a pully off the engine. it is pure electric. An electric motor is 100% efficient compared to the average engine that is more around the 30-35%. So although we in an HEV do use the ICE to supplement drive and recharge the battery, as a whole the A/C is far more efficient in the system as a whole. Compound that with by keeping the windows up, I am also not losing drive efficiency through reduced aerodynamics. I will have windows down when driving in a subdivision at 40-50kph (25-30mph) as the impact of aerodynamics on the car is not as great at these speeds as when you are driving at highway.
 

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If you have a small child, as do I, you know that opening ONE rear window does indeed cause buffeting and it is VERY annoying. Thank goodness for the window lock button!! :)
 

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So although we in an HEV do use the ICE to supplement drive and recharge the battery, as a whole the A/C is far more efficient in the system as a whole. Compound that with by keeping the windows up, I am also not losing drive efficiency through reduced aerodynamics.
As far as I know, this is a complete old wive's tale. I get the logic which no doubt drives this narrative, but it appears to be wrong. In my ICE car, the difference between windows open driving, and windows closed driving was about a 3 mpg hit to efficiency (over 10%). That's my anecdote and certainly the Niro AC is more efficient than that, but here is a test in a Tesla (which also has an electrically driven standard AC (not a heat pump)) by someone who believed the same thing. Bjørn Nyland is a Norway based YouTube star who is all about EV cars. Tends to have very long videos but this one is pretty short. Listen to the first few minutes and the last few if you need to save ten minutes.
 

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From the information I've received over the years, the break-point between windows down and running the A/C is 40-50 MPH. Below that, the aerodynamic change isn't enough to overweigh the MPG hit. Over that speed, then it's more economical with the windows up and the A/C on. Of course, this is all based on a gas-only car.

But for me, it's far more a comfort issue. I hate the noise and buffeting that I get even at speeds of 30 MPH. I have always accepted the slight loss of MPG for a higher level of comfort. As I approach my golden years (actually already residing there!) I place an even higher value on comfort over a slight increase in cost per mile. Driving under EV power, I greatly enjoy the quiet. :)
 

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Yup, that is how old wive's tales work, repeated over many years. Repetition doesn't make it true. Certainly drive your car in a manner suiting yourself for comfort. Comfort is your rationale, not efficiency.
 

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Yup, that is how old wive's tales work, repeated over many years. Repetition doesn't make it true. Certainly drive your car in a manner suiting yourself for comfort. Comfort is your rationale, not efficiency.

Where the test in the video was a part let down was that that the internal temperature inside the car was totally different. So he had the A/C turned on and got the temperature down to 23c where during the other two the temperature is at 28 and 27c. The second the third test was purely rather than having the car cooler, has a higher amount of air moving around inside the car. Now I would like to see if instead of setting the A/C to 20 and it running full time on the compressor and never actually getting down to that desired temp, if he would have done the same run with the A/C set to 26 (as that was the temp he said was comfortable with the fan set to 7 so you get the cooling effect of just air moving past your body. This way the A/C is only maintaining a comfortable temp and not running full time un-needed.




Also.. Please re-read what I posted. Your video linked I believe did show that there was a loss of efficiency between driving with the windows up and the fan blasting away, and driving with the windows rolled down 10cm. So YES you do loose aerodynamic efficiency. As well, I stated that in an ICE ONLY car the A/C is pulling the power off the engine. In the NIRO HEV it is electric so the A/C is more efficient compared to ... the ICE ONLY CAR. So how does what someone testing in a BEV have to do with anything? There is no ICE motor inside that vehicle at all. I bought my Niro Hybrid to replace a Gas Guzzling Crossover car. I didn't buy a Niro PHEV and clearly, I did not buy a Tesla or a Leaf or an E-Pace or any other type of BEV. I got a NIRO HEV.


The video went and tested the temp inside the car and it was a good 4-5deg difference. And he also stated that it was nice and quiet inside the car. Then you get to compare this with a car with windows wound down that is not only hotter (actual temp) but also much noisier. Yes with the setting chosen the A/C did use more power to run but how much more is it inside the Niro HEV?, and compare that to a similar size ICE only vehicle and what impact does that have on the fuel consumption?


I don't have the numbers, but if running the A/C in the Niro reduces my fuel efficiency by <5% I am not going to bat an eyelash at it, as I would rather have actual cool and none of the noise. (Heck, I have about 25-40% fuel efficiency loss running the heater and defogger in winter time for my comfort.) But all this is nothing compared to the on average 20% loss you get running an A/C inside an ICE car that is also multiple times more compounded with the fuel efficiency difference between my Niro Hybrid vs most every other comparable gas engines ICE car.



In your video test, you have a choice of getting 3.4% worse electric economy to get a cooler car with much less noise. I think I will take that any day at highway speeds. But everyones priorities will very depending on their wants.
 

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Not sure of your point here. Yes, Bjørn preferred the AC for comfort as do you. Fine, as I said. No, it is not as efficient as windows open. I also said the Niro has a more efficient AC than most ICE cars, including mine. As far as I can tell, you agree with me, and him.
 

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I had to take some smelly stuff to the garbage transfer station yesterday, so had a window down. I found the buffeting/roaring with a rear window down to be as bad as any other car I've owned, and with a front window down it just wasn't a comfortable drive. And this was never exceeding 45 MPH, and in most cases less than 40. Windows up for me as much as possible. :)
 

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It does take some fiddling with sometimes all four windows to kill the standing waves (perceived as buffeting but very different from buffeting from sticking your head out the window or on a motorcycle), but the extreme is never as bad as it was in my PT Cruiser. Standing waves are very sensitive to both the interior shape and the air flow or feed. In many cars I have been in, the largest source of noise was front passenger window all the way down with no passenger due to wind vibrating the seat belt on that side. Window half way up, noise vastly reduced.

First 30 years I drove, never had a car with AC. So windows or vents were the only cooling available. Used a spring coil seat cover but still baked on I-5. Anyhow, I got used to dealing with window adjustment and now I'm all about efficiency so I still avoid AC. I don't use AC until the outside temp is 87 and the sun is also shining. Then AC is a real luxury!
 

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It does take some fiddling with sometimes all four windows to kill the standing waves (perceived as buffeting but very different from buffeting from sticking your head out the window or on a motorcycle), but the extreme is never as bad as it was in my PT Cruiser. Standing waves are very sensitive to both the interior shape and the air flow or feed. In many cars I have been in, the largest source of noise was front passenger window all the way down with no passenger due to wind vibrating the seat belt on that side. Window half way up, noise vastly reduced.

First 30 years I drove, never had a car with AC. So windows or vents were the only cooling available. Used a spring coil seat cover but still baked on I-5. Anyhow, I got used to dealing with window adjustment and now I'm all about efficiency so I still avoid AC. I don't use AC until the outside temp is 87 and the sun is also shining. Then AC is a real luxury!
yes, I used to avoid a.c. like you but now with my phev and off peak electricity at 3.5 cents I use a.c. liberally. Really quiet and a cool breeze on my face :)

Assuming ac is 500w (I measured it), it costs me less than 2 cents an hour with a 2-3% hit on EV range to use it.

If only Kia had implemented a battery powered heat pump for heat ��. Almost instant heat in winter would be a big seller.
 

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Assuming ac is 500w (I measured it), it costs me less than 2 cents an hour with a 2-3% hit on EV range to use it.
Don't blame you a bit! On the Ioniq forum, most post they don't see a difference with AC use. Of course, that would be in the summertime when efficiency is better, at least for the HEV and PHEV, so it might be difficult to really tell.

How did you measure the AC consumption? Does the AC have its own motor or does it run off the serpentine belt?

Have you also measured the draw for creep at a stop? I saw a post on another forum that said it was 200 watts, and he apparently read on an OBD reader. Needless to say, I put it in neutral at any stop over twenty seconds, no need to be wasteful - would prefer no creep at all.
 

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How did you measure the AC consumption? Does the AC have its own motor or does it run off the serpentine belt?

Yes. The A/C unit on the Niro is 100% electric driven by it's own sealed motor. What makes this far better is that as a sealed unit, the coolent doesn't have any drive line seals to leak out of so it will likely last far beyond the life of the car without loosing coolant where an ICE motor driven one with a serpentine belt has a shaft that has a seal on it that will wear and as such you loose coolant slowly until you A/C works less and less. After ususally 5-6 years the seals are shot and coolent leaks quite quickly so you either need to keep refilling it each year or pay big bucks for a rebuild and hope that you can get 3-4 years more before it fails again.
 

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Don't blame you a bit! On the Ioniq forum, most post they don't see a difference with AC use. Of course, that would be in the summertime when efficiency is better, at least for the HEV and PHEV, so it might be difficult to really tell.

How did you measure the AC consumption? Does the AC have its own motor or does it run off the serpentine belt?

Have you also measured the draw for creep at a stop? I saw a post on another forum that said it was 200 watts, and he apparently read on an OBD reader. Needless to say, I put it in neutral at any stop over twenty seconds, no need to be wasteful - would prefer no creep at all.
The ac compressor motor runs on the high voltage battery.

I measured ac consumption by

1) parking in the garage
2) fully charging the battery
3) un plug the car
4) turn on the car and manual mode ac
5) X hours later turn off the car and ac
6) measure kwhrs required to fully recharge the battery
7) divide #6 by X.

Rough estimate only.
 

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Don't blame you a bit! On the Ioniq forum, most post they don't see a difference with AC use. Of course, that would be in the summertime when efficiency is better, at least for the HEV and PHEV, so it might be difficult to really tell.

How did you measure the AC consumption? Does the AC have its own motor or does it run off the serpentine belt?

Have you also measured the draw for creep at a stop? I saw a post on another forum that said it was 200 watts, and he apparently read on an OBD reader. Needless to say, I put it in neutral at any stop over twenty seconds, no need to be wasteful - would prefer no creep at all.
No. My tools/techniques are pretty basic.
 

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The ac compressor motor runs on the high voltage battery.

I measured ac consumption by

1) parking in the garage
2) fully charging the battery
3) un plug the car
4) turn on the car and manual mode ac
5) X hours later turn off the car and ac
6) measure kwhrs required to fully recharge the battery
7) divide #6 by X.

Rough estimate only.
In sunshine and high ambient when you did this?
 

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Don't blame you a bit! On the Ioniq forum, most post they don't see a difference with AC use. Of course, that would be in the summertime when efficiency is better, at least for the HEV and PHEV, so it might be difficult to really tell.

How did you measure the AC consumption? Does the AC have its own motor or does it run off the serpentine belt?

Have you also measured the draw for creep at a stop? I saw a post on another forum that said it was 200 watts, and he apparently read on an OBD reader. Needless to say, I put it in neutral at any stop over twenty seconds, no need to be wasteful - would prefer no creep at all.
I have a feeling, just from what I can feel at a stop, is that the creep is disabled while the brake is pressed, so no power consumption from creep at that time. Of course, I'd love to confirm or debunk that theory with facts.
 

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atc98092 would the fact that the Niro begins going backwards on an incline after you take you foot off the brake until hill assist kicks in confirm your theory?
 
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