Cooling Cars with Solar Energy

Arrrghhh....
Sledgehammernut syndrome.
The problem could easilly be designed out by suitable use of materials and not buying a black car.
Go for simplicity not added complication.
If you must add something.
It would be very simple to run the fan if the cabin tempreature exceeds a pr-determined threshold.
Unfortunately car manufaturers would feel obliged to wire this via the ignition switch/imobiliser/seat belt/handbrake/door locks etc to maximise the chance of electronic malfunction.

Del

In order to obtain cooling one has to push heat uphill along a temperature gradient. According to the lays of thermodynamics, energy is needed to do this, and the only place it can come from while the engine is off is the battery. Until it is flat, that is. So, what about the battery sizing? Larger batteries are more weight, and the charging current will require more power, which needs to come from the engine while it is running......

Sledgehammernut indeed.

A while back one of the mass marketers was selling a window mounted solar powered fan. I guess it did not work very well since it was only on those annoying television adverts for a short while.

I have one of those and it actually works. On the days I didn't put it in the window it was very noticable. I got it as a party gift. Thought it was crap until I stopped using it and saw the difference.

I have a solar battery charger, might find a muffle fan around here and make one myself. Just lay the solr panel on the dash...Thanks for the reminder.

Milo

They looked like they might work from what i saw on the television, nice to know they do.

I have a 6 inch computer cooling fan installed in one of the back windows of my Land Rover that I was to suck the hot air out. The only air conditioning I have are the side windows.

Thanks for the reminder. I have one of those window fan things too. They do work quite well. You can buy them at Walamrt or Kmart. Think they cost about $20.

An air-spaced panel above the existing roof (as used in the tropics on some Land Rovers, fuel tankers and other vehicles) makes an enormous difference.

Ah yes, the tropical roof, wish I had one, I really must get my act together and make one for my beast.

If you had a tank of air compressed & attached to a separate tank of water which could be sprayed/or dribbled onto the roof when high temperatures detected you would evaporate a lot of heat that otherwise soaks into the vehicle .

I know you all guys know it but then, just for records, 'leave a small slit open on the windows and you will not find it very hot when you come back'

capri,

'leave a small slit open on the windows and you will not find it very hot when you come back' - You probably will not find your car either .

Regards

Mr. W.A Snow

Did we not visit this topic a couple of years back? My original thoughts were to have a 'spoiler' type arrangement with solar panels charging a separate battery which would then drive a small compressor to feed a vortex tube, the cold end of which would provide a stream of cold air in the cabin. However, the gurus claimed this was far too inefficient, but who cares if the energy is free , the unit is neat, and it does the job (?).

Alternatively see cooling effect in Stirling engines. I believe you can work the magic with no moving parts, apart from a fan to distribute the colder air away, and passive regenerators.

Stirling engines are indeed a good option and it would be possible to drive one via a 12v source powered by solar voltaic array, perhaps mounted on the roof.

My aims to buy a Nano car.