If German exhaust system supplier Eberspaecher has its way, some of that currently-wasted heat may go back into powering a steam turbine, that may some day replace the alternator. The concept is simple: water is piped into a housing that surrounds part of the exhaust system. Residual heat from the exhaust vaporizes the water, producing steam that drives a miniature turbine blade. The turbine can then spin a generator, which can either supplement or replace a conventional alternator."
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