[figgy]

Solar Fan update

I was responding to a PM, but it's probably worth just letting everyone know I am still using the solar fans and very happy with them.

It really makes a difference, and I recommend it very much.

I did some specific checks a while ago where the car was in the sun. I had the windows cracked a small amount. When the fans were running from the sun power, the temperature was pretty much stable. As soon as I turned them off, it started to climb.

They are better at maintaining a cool temperature vs. cooling off a super hot car if it really is roasting - but what really does that other than AC?

I believe Mercedes has now included something like this in a 'hot weather package' or something like that, so that's a pretty good endorsement.

The only addition I did to the car I drive the most is to all a 5th fan up at the ceiling level to stir the air around even more. That helps on parked situations to keep the hot air from puddling up at the roof.

 

[Insightful Trekker]

Welcome back Figgy :!:

 

[ChoadNamath]

I hope it's not verboten to bring an old thread back from the grave, but I was wondering if anyone here has any experience with this type of solar exhaust fan setup? I'm looking to do something like this in my new (to me) Insight, and I'd appreciate it if anyone could give me some tips on how to do it best.

I was thinking about using 120mm fans, one on each vent. I was also wondering how people attached the fans to the vent, whether it was with tape/cable ties/staples/etc.

I'm trying to think through how to connect this up electrically... I'm getting one of the VW solar panels that can plug into an OBD-II port to charge the 12V battery, and I was trying to figure out which option would be best. The panel is a 5W panel that supplies a max of 275mA at ~18V. My preliminary thoughts are something along these lines:

1. Connect the fans to the car's 12V supply and keep the solar panel plugged into the OBD-II port to make sure the 12V battery stays charged (this would only be used when parked in bright sunlight). With only the one solar panel, I think this would still be a net drain on the battery, though, since the fans draw 160mA @ 12V.

2. Connect the fans directly to the solar panel without tapping into the car's electrical supply, and run them in series so that they would each have ~9V across them and could still run at their rated current draw even when the panel is outputting less than max power. I know running two fans in series isn't exactly ideal, but this would prevent the battery from being drained and would be easily dismantled if it didn't work out.

Anyone have any thoughts or suggestions? Thanks.

 

[JimIsbell]

The first post asked about getting more air through the vents. I assume this means while running down the road.

I was concerned about that as well because I try to keep the AC of as far into the summer as possible.

I fount that cracking the drivers side window about 3 " will give a greatly improved air flow through the vents because the problem seems to be back pressure in the car. And I can see no difference in mileage with the windows on both sides cracked 3". I got 91 mpg on a 120 mile trip yesterday with the windows cracked and the outside temp at 83F and I was comfortable. At the 120 mile point I had to close the windows and turn on the AC at 85F and the next 100 miles was 82 mpg. The AC cost more than the windows open!!!!

 

[figgy]

Still working fine

I have never had a problem with the solar fan installation so far in either Jane or Edwin, and I just used electrical tape to attach the fans to the vent ports. It has lasted years without a problem - a lot more than I expected. The fans and panels still work fine.

The details on the installation are in the bottom sections of the web page at:

Solar powered venting fans for forced air cooling of Honda Insight

I put a switch so I can power the fans from the battery instead of the sun (if it is super hot and no sun), but I have almost never used this at all as I always have sun if it is hot (here in CA sun is the driver for heat 99% of time).

I used more than one panel, and if you use more than one panel, what I would suggest is having the same switch box but setting A sends all power from the panels to the fans and setting B sends a bit to the battery for trickle charging and the rest to the fans.

If I were to change my setup, that is how I would change it.

Sometimes I got a long time without driving and the 12V can get low. The above would solve it - and maybe I should stop talking and do it!

 

[Varak]

My heat problem isn't from being parked, it is from driving 10+ hours/day in the Arizona sun and trying to avoid using the AC as much as possible to save on MPG.

I have a very high heat tolerance, but once the temp passes 95/100 in the car, I start getting reduced regen which I've read is due to the battery getting overheated. I'm beginning to think I should run the AC as much for the battery as for myself.

Before I do that, though, I'm thinking of using your quadfan installation idea and simply wiring it into the accessory plug so that it will be on whenever I'm driving to help ejecting hot air from the car.

Do you notice a significant reduction in cabin temperature when you run the fans while driving?

 

[satchel]

I'm thinking avoiding use of the battery as much as possible may be your best strategy. Especially when experiencing the hottest temperatures. The Calpod switch mod would let you turn off IMA use or you could consciously try to keep from using any assist(it's about unavoidable in second gear). The Insight is quite capable of getting around on the ICE alone.
I don't think the little computer case fans would do nearly as much while driving as running the dash fans wide open and/or cracking windows open a couple of inches.

 

[JimIsbell]

Yesterday I discovered an interesting "function"...maybe....

I turned on the AC and then hit econ to turn off the compressor. I recycled the compressor on and off as I drove on the highway with the temp set to 60. I do this because I don't like the Insights method of moderating temp (mixing hot air with cold to get the temp right) because it is not an efficient use of energy. So I just tap the ECON button on and off as needed to keep the temp reasonable. I then later turned off the car while in the AC off (NO, not the off switch, just hit ECON) configuration. When I got back in the car there was a substantial flow of air from the vents when moving and none while stopped...so it wasnt the fan, which showed to be off. Then hit the OFF button twice (on and off) and I found I still had a ram air flow. It seems to be more flow than any other position and it was with the windows closed. Maybe the vents are in a different position when left in AC off/Econ mode??

 

[3-Wheeler]

I'm with Satchel on this one. The idea of using the IMA disable switch to effectively reduce assist when the outside air temperature is hot, like 85 and above is exactly the reason that this feature was added to the car.

Wisconsin usually has several weeks where this type of temperature can easily bake the battery pack, and using this switch can keep assist to a minimum and save wear/tear on the battery during this time.

The switch has the further advantage of keeping the battery from depleting itself in heavy stop and go traffic, or traveling up long hills.

Jim.

 

[Varak]

Living in Phoenix, I'm not sure how much of an option that is, though.

I'm a courier driving 200+ miles/day with half freeway and the other half spent stopping and starting in heavy traffic which seems to be the worst possible conditions for the car.

Using the AC is a catch 22, because it ends up requiring more assist in stop and go traffic which just makes thing worse. But when its 100+, without AC, the ambient temperature in the car easily hits 90+ even with the fan going full blast. That probably puts the battery pack at 120-130+.

And once the battery is heated up, it takes forever to cool down even when I'm back on the freeway and the AC is going full blast.

Does a Scangauge (or a laptop running an OBD program) allow monitoring of battery temperature?

 

[JimIsbell]

I'm with Satchel on this one. The idea of using the IMA disable switch to effectively reduce assist when the outside air temperature is hot, like 85 and above is exactly the reason that this feature was added to the car.

Wisconsin usually has several weeks where this type of temperature can easily bake the battery pack, and using this switch can keep assist to a minimum and save wear/tear on the battery during this time.

The switch has the further advantage of keeping the battery from depleting itself in heavy stop and go traffic, or traveling up long hills.

Jim.

WOW, that would kill my IMA from a week ago, about May1st to September 30th That just cant be done down here!!! Thats 6 months out of its life!!!

 

[JimIsbell]

Living in Phoenix, I'm not sure how much of an option that is, though.

I'm a courier driving 200+ miles/day with half freeway and the other half spent stopping and starting in heavy traffic which seems to be the worst possible conditions for the car.

Using the AC is a catch 22, because it ends up requiring more assist in stop and go traffic which just makes thing worse. But when its 100+, without AC, the ambient temperature in the car easily hits 90+ even with the fan going full blast. That probably puts the battery pack at 120-130+.

Have you tried putting the AC in econ mode and then cutting the compressor on and off, depending on your situation, by just a tap on the ECON button?

I set mine to 60 degrees and then ECON. This way it stops when ever the car goes into FAS and restarts when you pull away. I further use the ECON button to shut the compressor off when accelerating or climbing a hill and turning the compressor back on when descending a hill or on a long flat streach with just a tap of the ECON button. Put the fan on 3 boxes this will keep the car cool even when the compressor is off for a short time. It works fine down here in South Texas.

Another method is to leave the compressor off as long as you can stand it then turn it on only till the car gets cold....ALWAYS leave it on 60 otherwise you are mixing hot air with it to maintain the set temperature!!!

 

[3-Wheeler]

Jim,

Yes, I see what you mean regarding the very hot temperatures down there in Texas. Fortunately I can get away with using the IMA disable switch for a short period over the summer.

Up here, we have very cold Wisconsin winter days, when we are scrapping thick layers of ice off our windows and wonder why we don't live in a warmer climate.

But then spring finally arrives and we are content to stay another season, and don't think about those cold days again until late fall.

This is the time of year when I'm glad to be here again!!

Jim.