Article on cabin temperature (and traction battery temperature) when parked

This looks about right.

 

Of course, on hot days when the car has been exposed to full sun, I open the windows before I even enter the vehicle, to release the initial heat. After that, once the car is started the engine has to go through its initial start up to preheat the catalectic converter, this is a perfect time to start the A/C as the engine is already running allowing it to start cooling the vehicle before it has a chance to start running on batteries. By the time the engine has shut down the initial start up current has already past. Unless of course you like sucking 120 degree air into your Traction Battery, I don’t.

 

If this is true then you are free to leave your favorite pet or a baby in the car while you go to work, as they will show no ill effects according to your incontrovertible empirical data. What temperature recording system did you use to establish this impressive finding? You should also contact the people responsible for the initial study and explain to them the errors in their methodology. I also look forward to your data being used for the next add campaign for the sun shield and tinting. The cracked windows were the most effective thing that could be done to keep cabin temps down, the problem with this is, of course, the security of your vehicle and is therefore impractical in many locations.

By the way 1 degree Celsius equals 1.8 degrees Fahrenheit. The highest difference found was around 6 degrees C, this equals 10.8 degrees F. Most temperatures varied between 50 and 60 degrees C this equals 122-140 degrees F. Even if you could hold the temp to 110 degrees F, this would certainly be very uncomfortable and dangerous to the elderly, the very young, and pets, it would also still be too hot to adequately cool the Traction Battery. You can always drive with windows down, which should cause little drag at city speeds, however you still can’t bring the cabin temperature below ambient by doing this. If the ambient air temperature is 80 degrees F or below this is probably adequate, as long as the humidity is fairly low. If the ambient temperature is above this with moderate humidity, I would still want to use A/C. It is a lot easier to pay attention to ones driving if one is not constantly wiping sweat from ones brow. The sun beating down on you, causes your body to heat up above ambient air temp as well, so the A/C would be faster at removing that heat. It is also easier to drive when one is not suffering heat stroke.

 

I'm sorry. You must have mistaken me for someone who may have been talking about leaving humans or animals in a parked non-running car. I was discussing fuel economy.

As for the max temp difference, which is it? 10.8 degrees F or 18 degrees F? I didn't go back to re-read the article and was going off memory as I stated. Please clear up this confusion on both your part and mine. It appears the windows up (136.76) vs. windows down (117.68) test came out to a difference of 19.08F avg or 21.78F peak. The sunshade test showed a 4.5F difference in favor of the sunshade. The tint was a mixed bag but since we don't have any real data on ceramics I'll refrain from speculating on the effects. So if you are able to reduce in cabin temps by 20 degrees or more this could have a beneficial effect on fuel efficiency and human comfort when entering the car.

 

I didn’t include the windows down result as someone else complained that their results were flawed because they did such a test. Of course, if you live in an area where no one will steal your car or its belongings if you leave the windows down, then by all means leave them down, as this was the most effective way to reduce cabin air temperatures in full sun. I often do the same when my car is parked where there is no threat of theft. I also seek out shaded parking spots whenever possible as this is far more effective than sun shades and window tinting as well.

You all were bashing the results documented and published by this organization, claiming that their results were somehow in error, and inconclusive. If you read the original reason for this thread it was to draw a correlation between the dangers of high cabin air temperature to living things and the Prius’ Traction Battery, there was no discussion of fuel economy. So here you are complaining about their results and applying them to something that was not part of their research or part of the original thread for that matter. I will gladly sacrifice a couple MPG for the comfort and safety of my car’s occupants, as well as the longevity of my Traction Battery.

It seems to me that the real problem you have with these results is that they show the relative ineffectiveness of the sun shade and window tinting that you purchased, and frankly if you leave your windows down as you suggest, then I would argue that almost all your benefit comes from that fact alone. The one place where the sun shade and window tinting is helpful is in regards to high surface temperatures of the seats and steering wheel, which I acknowledged in my first post. Of course you could throw an old white sheet over them and get the same results. I used to do that in my cars years ago, back before I purchased cars with A/C, but it doesn’t look as COOL, and we all know how important COOL is.

 

The OP made no mention of posting this article in regards to living things. It is clearly stated that the reason for the post is based on cabin temperature and its effects on battery temperature. I was adding opinions on HV battery health and overall fuel efficiency as that is a pretty hot topic during summer months. So unless you care to refute my opinion I don't see where you have anything to argue. Based on your very first thread, however, I can see that you like to argue.

I'm happy with my purchases. I bought the tint to make the car look nicer and darken the interior. I purchased the sunshade to reduce cabin temp and reduce heat soak on the dash. Both purchases have satisfied my desires.With the addition of the solar roof I have a car that is perfectly comfortable to enter despite sitting for hours in 100F+ temps.

Lastly, I did not bash the authors of the study nor their results except that point out that the measurements were taken in Celius and not Fahrenheit.

 

He also appears to carry around multiple chips on his shoulder. I will not be surprised if his nickname is "Dick."

 

Not to mention that if the A/C is in AUTO that it will automatically recycle inside air which will be much hotter than outside air for a while thereby making it less efficient.

 

The living things were mentioned in the study and the correlation with the Traction Battery was the reason for the initial post. In other words the temps that are consistent with human health and comfort are also consistent with proper traction battery temps, why is this so hard to understand?

Now your statements are opinions, which is fine. So long as they are not confused with factual data, I see no reason to refute them.

I don’t necessarily like to argue, but since when is a good debate a bad thing?

I am glad you are happy with your purchases, and that they make your vehicle feel comfortable to you. Just remember, what you consider comfortable, someone else may not.

Your post came across to me like a complaint that the study was done in Celsius; however seeing that it was conducted in Australia I didn’t see why you would have expected any different.

 

You call yourself a sage, which suggests a person of great wisdom, so I find it sad that you would resort to name calling. I have not called anyone that I disagree with, an insulting name.

 

Note that UV cannot pass through glass.

 

Except about 90% of UVA right?

 

This is true.