Thanks for the explanation. It seems to me you could have as much as a 40-50 degree differential between in-car temp and outdoor temp (say 110 inside in a closed car in the summer vs. 70 outside) and it wouldn’t be that big a problem to engineer something that had the cold side on the outdoor side.
If there were a 40-50 degree F. difference, how much juice could be generated? A practical amount? Again, just curious. After all, this is truly waste heat, and it’s generated all day long while the car is sitting in a parking lot at work. If it worked, people might even start to hoard the sunny spots like they currently do the shady ones.
With current technology, my understanding is that a 40 - 50 degree difference wouldn’t generate much. However, most of today’s devices are geared toward stoves of some type or exhaust pipes, to get 200 or more degrees differential. This is probably due to the limits of current TEG technology. With new materials, a smaller temp differential would produce more, and trickle-charging a big battery over 8 hours or so would likely make a lot of sense. I guess that we simply have to wait for devices to be made to know for certain.
I am, however, much more excited about this technology than solar - you don’t need the sun to shine to have this work, and as time goes on, this appears to have the ability to increase more in efficiency. The devices are also a lot more mobile, due to not needing sunlight or even any light at all (like using the heat from a truck’s or car’s exhaust at night).