BMW is getting a lot of headlines about putting Thermoelectric Generators in cars.  Rightfully so.  But this headline really caught my attention:

"BMW testing Radioactive Exhaust Energy Generator"

It's not true, of course.  Nobody is putting anything radioactive into cars.

The mixup seems to stem from the purported NASA-connection.  NASA does indeed use radioactive heat sources to power some deep-space missions.  These so-called "Radioisotope Thermoelectric Generators" or "RTG's" utilize heat from radioactive plutonium, which is turned into electrical energy by thermocouples.

For automotive applications, waste heat from the engine and/or exhaust is turned into electrical energy by thermocouples.  Nothing radioactive is involved in these systems at all.

The link above has the worst headline I've seen, but there are several internet postings connected to the BMW R&D in the past week that mangle the radioactive aspect.

Just to be clear let's all say it one more time:  there is nothing radioactive about thermoelectrics in cars.  Sheesh.