There are a few threads on thermoelectrically recovering waste heat from the exhaust, for example
VW Golf with exhaust thermoelectric power: +5% MPG . But maybe putting thermoelectrics on the radiator might be a good idea. I'd think it's at least as hot as the tailpipe. And aspera is right: maybe the best place to recover waste heat from is the turbo or intercooler.
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e·co·mod·ding: the art of turning vehicles into what they should be
What matters is
where you're going, not
how fast.
"... we humans tend to screw up everything that's good enough as it is...or everything that we're attracted to, we love to go and defile it." - Chris Cornell
[Old] Piwoslaw's Peugeot 307sw modding thread