Just after 9/11 there was a total fly-ban in the States. The lack of con-trails gave a significant difference in day/night temperature intervals (3°C IIRC). If we are heading in to a higher cosmic-ray, lower temperature regime, then extra-thick con-trails will be a problem and will reduce the farming yield. Could be a high price to pay for cheap flights.

For ground-based systems, where you can absorb the mist produced and not let it out, this would probably work, and especially for individual-sized generators could be good. Fill the tank with water and get electricity.

I haven’t yet seen replications of that research yet, though, so could be a mistake in measurements. Worth a test.

Some versions of free energy could end up being more costly in other ways.

The problem is getting to over unity, though. I’ll tell you when I’ve got some auspicious figures. At the moment, where I can estimate figures, the result is not even 100% efficient. It seems Papp got a COP of around 80 but no-one knows whether this is really true or was fudged somehow. It’s worth the effort to find out, though, since if it is possible then like LENR it will change the world for the better.

A single double-ended cylinder would give some vibration problems, but put 4 of them together and get the timings right you can get over that. If it can produce more energy than it consumes, then the rest is just engineering and there are a lot of examples of ways people have invented to get round those sorts of problems. Before building an engine to use the effect, it’s a good idea to make sure the effect is well-measured.