Take that ammonium, burn it, have heat, power a steam engine, infinite energy?
Where does that energy come from? 1st law of thermodynamics?
replies(6):
Where does that energy come from? 1st law of thermodynamics?
One aspect of these miracle solutions to watch out for: the catalyst is often very expensive and has a finite lifespan.
Edit: actual paper https://www.science.org/doi/full/10.1126/sciadv.ads4443
Edit: got to the bit in the paper where they describe the process; "contact electrification". This appears to be an electrostatic phenomenon like tribocharging (the old "rub a balloon on your hair" trick). Water droplets hitting the catalyst generates enough potential at the surface to trigger a reaction. So I suppose the energy input is actually in the spray+pump of the experiment, or wind in the outdoor example.
The resulting output is extremely dilute. Raising the concentration is likely to consume more energy for generating an actually useful output.
Worse, they seem to be using some chilled object to condense ammonia solution from the air, so you’re also paying the energy cost of keeping it cold, which means you’re paying the full cost of producing a lot of water from atmospheric water vapor. Maybe a future improvement could start with liquid water.