Solar Roof - Does it work?

i found the solar panel will work in ambient light without direct sun, but not very well. i sat in car about 2 months ago and checked its progress. was about 9.30 PM and had, at best filtered setting sunlight thru trees.

fan on, med low speed (guessing by sound) ran 15 seconds shut off. for about 30-45 seconds, then came back on again. and that is about how it ran.

for comparison. at 2 pm in nearly fun sun, fan would run (granted nowhere near as comfortable so did not check this much) nearly all the time and at probably medium to one notch past half way speed. it did shutdown once but then started back up again after about 10 seconds. after watching it run about 7-8 minutes, i gave up on trying to decide how long it would run again before stopping

 

That's why I simply ordered the Japanese market OEM window rain guards... so I can do my "own" solar roof... leave windows open a crack, heat shield in front window. A lot cheaper.

 

My solor roof does power up the fan, but I dont think it "efficiently" lower the temperture in the interior. I live in CA, so the fan helps a little, but the interior is always hotter than the outside.
I find open the moon roof a little does help the hot air escape from the top.

 

The solar panel does work. I've been comparing temperature readings with solar vent on and off, and with or without a windshield heat shield. I can't open my windows because of dust. When it is very hot and sunny (~100F) the car interior will be about 125 with vent running. Without the solar vent the temp will be over 150F. When the outside temp is ~90 the car interior will be around 105 - 110 (these measurements taken in full sun). In cooler temps the vent is even more effective because it sucks in the cool air from outside and the car interior temp will be closer to "ambient" I've been taking readings without using the remote AC unit because I was interested to see how much difference the solar vent makes. It is actually comfortable when you get in the car and I'd rather use the power stored in the battery to drive the car rather than cool the car down. I've found that just using the solar vent, the car is cool within a couple of minutes of driving. I believe using the remote AC is unnecessary (unless you are entering the car with an infant, etc, or just plain love AC). Finally, in full sun the vent is blasting at high continuously, as somebody noted above. I'm going to edit my first entry in the thread "Solar Roof Temperature Report" so it includes all the data from mulitple temperature readings... that way people don't have to wade through multiple pages to get answers.

 

Bearpaw, I have a Prius IV with Solar Roof; here are my thoughts:

"solar roof cooling system really works." This is a ventilation system, not a cooling system.
"Does it efficiently lower the interior temperature?" If by "efficiently" you mean without draining the cars power, the answer is yes. It efficiently keeps the temperature from rising in the car as high as naturally would without the solar roof. It DOES NOT lower the interior temperature. It circulates the existing air with a ventilation fan to prevent the temperature from rising in the 130 - 150 degree range.

"Is it true that it will only work in direct sunlight or can you park under the shade of a tree and still have it function." My understanding is that this is correct. The solar power collected and converted by the roof panel does not store any energy, it uses the energy it creats to drive the ventilation fan; that's all.

"Finally, how well does the system work in humid climates?" I live in Denver, Colorado. I'm at 5200 feet with very little humidity.

"If you have temperature readings, especially those of you in humid climates, could you post them?" When it is 85 degrees, or so, outside my cabin has been about 105 to 110 degrees. That in direct sunlight at one mile in altitude where the effects of the sun are significantly different then the heat effects of the sun at sea level. My car is noticeably cooler than my previous car when parked outside, even with the windows cracked.


"1. GET A HEATSHIELD! - Definitely
2. Crack all the windows about an inch or so. I can't speak to this, I do not crack my windows and I have appreciated that my car is not broiling hot and I can touch the steering wheel without burning my hands.
3. Use the SR in conjunction with the remote a/c, which is how it is designed to be used. The remote A/C has a limited range and time duration. It won't run the battery so low you can't start the car.
4. Ambient means "close" and that's exactly what happens. Don't expect the same int/ext temp. It's not going to happen." I agree.

Regards, --TK

 

I got a private asking about this, Sigma has them under "Window Visor":

Toyota Prius 2010+ ZVW30 Exterior Accessories :: Sigma Automotive

 

I've heard SR owners say they got SR so they don't have to look for a shade to park under, but they're more likely to end up with faded paint.

 

The Solar Roof (SR) is a great option that really works! It keeps the interior close to ambient temperatures without allowing dust and bugs in. Using a windshield sun shade will also help, but when the the SR is working, the A/C will not have to work as hard cooling the car interior down - it it already cooler than an oven, so you will feel cooler, sooner. I hate cracking the windows since that is an open invitation to thieves.

 

I was thinking you could open the Sun Roof too just to the initial position though. Of course, only if it doesn't rain.

 

It works! Dramatically on a sunny day when the temp is in the low to mid 80's F. Less dramatically in the 90's because you become aware of the actual heat, rather than how hot it could have been. Now when I feel the fan when I get on a hot day in NC, I can't imagine being without it. You don;t need to open windows. The remote a/c is a nice luxury touuch but it ain't really part of it.

 

Okay, I need to defend myself and getting a bashing - my salesman is the one who suggested I crack the windows an inch or so. It wasn't my idea.

I park 100ft. from my car at work (in plain sight) so rain & theft isn't an issue. Otherwise, for goodness close your windows if it works for you. I personally don't care.

I garage my car at home, so all of this is a non-issue for me.

What is the saying, "Whatever floats your boat."

 

I've been cracking my car windows in Florida for over a decade. Never once has a single bug wandered in. I guess the hotter interior is simply not appealing. (90 outside, 100 inside)...

Also, I really don't think anyone will be able to steal the Prius with a window cracked. It's all electronic key ignition. Even gaining access to the lock/unlock switch is a nightmare, easier to jimmy the door. I'd consider it "false security" to assume the window closed all the way in any way prevents those who are determined to get access to your car interior.

 

RickFlashman - YOU ROCK! I couldn't have said it better myself.

After reading my last post, it appears to me that I need to slow down my fingers and let my brain catch up. I'm missing a couple of words. Sorry.

 

I wish I could FIND a Prius with the solar package here in South Texas! :frusty:

I'm thinking of buying one from a California dealer, flying out there, and doing a vacation drive from San Fran back to San Antonio! lane:

I actually had a salesman tell me that he didn't see why anyone would want a sunroof/solar package here in South Texas. I reminded him the solar panel ventelated the interior, and with the remote A/C that comes with the package, I could turn on the A/C BEFORE getting in the car, thereby getting in a cool car. BTW, it was 105 degrees when I explained this to him. Suddenly, I could literally see the light bulb come on inside his little brain.....

Good luck to those of you who HAVE a solar package-equipped Prius!

Joe

 

The primary benefit of the solar roof, I suspect, is improved battery life. Batteries are damaged by heat. If the solar roof keeps the interior of the car warm instead of hot, then the battery will benefit a lot in the long term. I've never seen this as a stated benefit, but I'd love to hear what the engineer-types on this forum think.

 

Bottom line is that the Solar Roof does work and effectively cools down the interior. I think some people expect an ice box from it, but that is not the case. It will simply come close to ambient temperatures.

The real question is wether or not it is worth the price. I like the look and the functionality so I am not upset at the high cost. I do however understand that I paid a premium for new technology.

 

I have seen a difference on real hot days. The air in the car is not stagnant because of the fan.

 

Hang in there - I had to drive to Louisiana to find and pick mine up. Well worth traveling to where ever one might have to go.

--Mickey