This week’s video comes from Columbia University where researchers have utilised evaporating water to create a floating, piston-driven engine that generates electricity, and a rotary engine that drives a miniature car.

When energy from evaporation is scaled up, the researchers predict, it could produce electricity from floating power generators, or from rotating machines akin to wind turbines that sit above water, said Ozgur Sahin, Ph.D., an associate professor of biological sciences and physics at Columbia University and lead author of a paper detailing the research in Nature Communications.
This is fantastic and wonderful, and reminds one of the Nitinol alloy engines of years past, that based structure memory on temperature. If you really want to harness large power from evaporation, you must couple that with condensation (using high towers) that produce a complete cycle, and gain energy from both rising vapor and falling water. It takes a combined machine operating all of these principles at once to gain the most.
This is a waste of time and money. This will never have a practical use. Great science, but a total waste of time and money. It amazes me how great minds end up do childish science.
So they’ve re-invented the steam engine and before the nit-pickers tell me it’s not a steam engine but a water vapour engine, may I just mention the precedent set by James Watt who’s water vapour engine was called and is still called a ‘Steam’ engine.
The costs producing commercially practicable implementations of such low temperature ‘steam’ engines must surely outweigh any benefits possible. Consider also the sheer size of such devices if scaled to practicable levels.
Waste of time, but maybe a useful example of ‘Grant grabbing’.
As a lab experiment, this is entertaining and educational. As a source of power on any substantial scale, it is clearly hopeless.
Columbia’s use of spores is curious. There must be numerous polymer compounds and gels that would similarly exhibit expansion and contraction depending on moisture content, and which would be cheaper and easier to work with.
It’s not the first engine to capture energy by evaporation.
Here’s one that was patented in 1946: https://www.youtube.com/watch?v=cwyDsHG-ymQ
It works on a different principle internally, relying on cooling due to evaporation.
To get some real power out, apply concentrated solar heat to drive the evaporation, make steam and run that through a turbine linked to a generator. Lots of examples at https://www.youtube.com/playlist?list=PL8WwWQL2xBdAm81H6EGr9usCYN7aZiUk7
Great idea……good thinking to get inspired by nature. To those people who comment that this kind of research is wate of time I would say…….it’s too early to say its waste of time….and even if it appears later on that it does not work, i am sure there are side effects and inspiration for other new things.
Congratulation and I very much would like to be involved. Please look to our instite http://www.wetsus.nl
May be we can join forces.
Best regards and succes
Gerrit Oudakker
Technology scout