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‘It was an accident’: the scientists who have turned humid air into renewable power
(www.theguardian.com)
This is a most excellent place for technology news and articles.
It won't (my personal totally empty prediction). To get humidity in larger scale it means getting air flow. Air flow in sufficient numbers doesn't come out of no where. Usually with this kind of stuff one quickly finds one needs just insane amount of flow to scale meaning big blower fans and then you find you spend all the energy you produce running the fans and other needed ancillary equipment.
And when you start stacking the layers you need pressure to push the air through the layers and so on meaning, supply fans. Otherwise eventually on big enough system you find.... the system sucks all the moisture out of the air locally and then no more electricity. They aren't pulling energy out of air, but out of humidity . First is plentiful in atmosphere, second is at times very finite quantity locally. Sure on the wider atmosphere the humidity is plentiful, but again how you get that humidity to the device constantly. There needs to be airflow. With small enough device like those micro watts, well the humidity present ambiently is enough, since it consumes next to nothing. Start to scale up and well the ambient humidity is not enough. Not unless you are at windy sea front at which point.... why not just put up a wind turbine and a sea front sea wave power station.
It might find utility as small local power source with not much power required, but grid scale thing it most likely won't be. aka it isn't hog wash, but when they start talking "yeah, but we put 100k of these disks in a stack and it will be this much power" you must start asking "so how many kilogram of H2O is that thing ingesting per minute, is there that much H20 weight in the air in the first place. If not how big fans and turbine you need to drive new moist air to it".
It's possible to use direct mechanical power harvested from renewables to turn the fans, though depending on the effiency it might make more sense to just convert that mechanical power directly into electricity. But, for example, a windmill (as opposed to a wind turbine) could harvest large scale natural air flow and then mechanically leverage that to move humid air at a smaller scale. Same with dams.
Is it possible that this could be included in modern wind turbines to increase efficiency?
Not atleast to the blades, this needs air to flow through it, wind turbines need air flow to push the blades. Exact opposite needs. Any flow through thing like this would cause either loss of power as the blade itself or source of drag as ancillary to the blades.
Like one could put one next to wind turbine, but question is their sense in it. Why not just use the turbines directly and put up extra turbines at expense of this machine.
They would have to have amazing full cycle efficiency to make it work. Not like that doesn't happen at times like heat pump powered by electricity being better than direct electric heating. However as said they would have to show pretty amazing efficiency numbers and at scale. Just because it works in small scale in lab doesn't mean it works at large scale or outside of sterile lab environment.