MSimon wrote:
I believe for an IC engine 1/3 of the energy is power out. 1/3 goes into the cooling water. 1/3 out the exhaust. Roughly.
But isn't the "cooling water" third there just to remove excess heat from the engine? Why cant we use these systems as a way to extract heat directly from the engine or at the very least run the coolant over the thermoelectric device. This will reduce the wear on the radiator (maybe even permitting a smaller radiator system) and generate extra juice.
So really we are going from 33% to 47%.
The real trick is...will the weight be worth it?
No. Cooling water is not just to remove heat. It is to keep the engine at optimum operating temp. About 110 to 120 C. That limits the amount of energy available. Carnot.
And yeah. Getting the price right will be a while. If ever.
Engineering is the art of making what you want from what you can get at a profit.
I remembered an old article on piezo-converted thermo-electricity, managed to google a reference to the infamous July 1992 feature in Electronics and Wireless World...
If I've understood and/or remembered correctly, the process works in a semi-resonant mode, so power levels and conversion efficiencies are much higher than steady-state. Akin to LC 'tank' feeding useful signal to diode...
Two cautions: Site's old, unmaintained, so there's a bunch of 404 links. Also, one of the authors seems a tad eccentric...
Still, explore and enjoy...
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FWIW, I still giggle every time I see a lab-demo of thermo-electro-magnetism...