Steam engines could be eco hope

The search for a suitable alternative fuel source to hydrocarbons which can cleanly power our vehicles has touched on various different options.
Fuels which do not “rot” the environment usually bring to mind images of gently humming electric cars, clean hydrogen, natural gas, or hithane – a concoction of hydrogen and methane. Steam engine and boy
Steam engines usually conjure up romantic images of days gone by.

BBC