Once again my new car and its differences from the old car spawns another idea. This car is hot and whether I park it in the shade or no, the inside temperature is at the very least in the high 90's during this summer.

So why not add exhaust vents in the roof and intake vents in the floor. The vents can be closed through using a door (such as an exhaust vent in a kitchen) and also will use a screen mesh to keep out bugs. In either the exhaust vent, intake vent, or both there will be a small fan that will be hooked up to a small generator. As the hot air rises out of the car and cool air is drawn in, the fans will move thus creating a current to charge the battery.
-- MrDaliLlama, Aug 28 2004

vent http://www.amerimar...dia=G01094&days=XVQ
look what I found on first try and so cheap too. [dentworth, Oct 04 2004, last modified Oct 05 2004]

Proprietary Thermionic Device http://www.eneco-us...m/news/improves.htm
This may be a better idea... [shapu, Oct 04 2004, last modified Oct 05 2004]

Basics of Thermoelectrics (sorta) http://www.electron.../SEP96/sep96_04.htm
[shapu, Oct 04 2004, last modified Oct 05 2004]

Add a 200 foot chimny, and you'l get some power out of it. Otherwise...
-- my-nep, Aug 28 2004


This idea was posted a few weeks back. I remember annotating about making a whirly-gig generator for your house, but the idea seems to have gone kaplooie.
-- 2 fries shy of a happy meal, Aug 29 2004


I have one of the fans in dentworth's link. I can't say that it works very well.

I can't feel any air movement around the fan. I keep wanting to do a smoke test or something to see if it actually moves any air. Oh and I paid $15
-- swamilad, Aug 30 2004


Actually upon rereading, the original idea is to make a windmill type generator inside the car. Can't picture that happening with a little puff of hot air, [MrDL]
-- dentworth, Aug 30 2004


interesting concept, but with such a short "chimney", you won't have enough pressure differential to do any useful work.
-- Freefall, Aug 30 2004


It might be a better idea to simply find some sort of thermoelectric device and install a series of them in the interior ceiling of a car.

MIT scientists have just built one that works to convert 17% of heat to electricty at 250-300 degrees C. We have some work ahead of us.

See linkies.

So basically, the title of the idea is sound and theoretically possible. Your method of getting there is not.
-- shapu, Aug 30 2004


Nice Idea, but I think this one sort of falls under the category of putting a smokestack over the toaster. Neutal on this one.
-- ye_river_xiv, Feb 01 2007


i know your idea relied on the chimney-like effect, but this might use your same airflow more efficiently.

if you were to insulate the car a little better (for roasting babies and puppies), you might be able to get a temperature differential of 50C on a hot day...

lemme see, if it was 80C in the car, and 30C outside, the most energy you could extract using a perfect heat engine would be about 14% - in reality maybe <5%. That would still be enough for a little LTD Stirling engine to run a small generator and charge your batteries, so + coz it would work... but wouldn't it be easier to just shade the windows with PV panels?
-- TIB, Feb 01 2007



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