Visiting Australia recently made me think a lot about the dangers of bushfires.
Today’s invention is an attempt to help.
When a fire approaches one of a number of outstations, the temperature difference between the firefront and underground can be used to power eg a Stirling engine.
This could then be used to automatically pump water onto the roof of a building under threat, damping down any windblown sparks and smouldering embers.
I’ve just come across this interesting device which seems to work on a smaller scale: http://www.biolitestove.com/BioLite.html