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Fascinating history, thanks. I came across two incarnations of the trompe idea on Youtube that might be of interest.

The first was what the author describes as a hybrid of a trompe and a water ram. He used a small stream and 8' of head to accumulate air in a PVC pressure vessel to 60psi.


The 2nd was of a guy who got a grant from US DOI to use a trompe to help cleanup iron polluted water at an old mining site. The compressed air aids in oxidizing the iron to cause it to settle out.


Tyler August


Dr. Millar's HAC Demonstrator is installed in the Big Nickel Mine at Dynamic Earth, a geology-based science centre in Sudbury, Ontario, Canada. Part of the agreement with the science center is that the public has access to view the experimental facility and ask questions of the researchers.

Research is ongoing, so if you're ever in the area, it's worth checking out. One thing they are currently exploring is adding various salts to the water at the HAC demonstrator to reduce gas solubility and increase efficiency even further.

kris de decker


@ akb

Thanks, interesting. George Fleming also wrote me that the trompe could be used to reduce the dead zone in the Gulf of Mexico:

"It could inject air into the water while bringing cold bottom water up to the surface, like a Salter Sink, and producing bubbles at the surface which would increase reflectivity of the water, reducing warming. The compressors could be powered for free by the wind. This would work for any dead zone in any waters".

John Davies


Locomotives running on compressed air have a long history - http://www.douglas-self.com/MUSEUM/LOCOLOCO/airloco/airloco.htm.

Often used for short distances where range wasn't a problem, e.g. shunting, or for environments where a steam engine was hazardous, e.g. underground.

Logan Simmering


"Obviously, compressing the air mechanically only works with windmills and not with solar PV panels, which do not produce mechanical energy"

Solar thermal systems could be used to produce mechanical energy, as seen here




Couldn't return air shafts provide wind tunnels to exploit the air for power?

Charles R. Patton


Mentioned in article:

"Once again, it pays to look to the past for inspiration. Surprisingly, the holy grail of “isothermal” air compression – in which no waste heat is produced at all – was found at least 400 years ago. The hydraulic air compressor – or “trompe”, as it was originally known – was an Italian invention first mentioned by name in 1588, but possibly already known in Antiquity."

A very old 7th century as referenced in:

Roman forge, the "herreria de compludo" in Spain uses (it has been restored) a trompe for pressured air to run the "blast" furnace and various forge charcoal beds around the water wheel powered forge hammers. So it appears that the trompe concept existed at least 1300 years ago. As it was Roman, the concept may have been passed down through the generations as it is very simple and reliable with a good supply of water.

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