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Comment by jmiskovic | Hacker News Reader

This design is among many low-tech alternatives to modern appliances and processes mentioned in book The Knowledge: How to Rebuild Civilization in the Aftermath of a Cataclysm. It was not successful because of already established industry of refrigerators that were good enough. The book is excellent.

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Thanks for the book, I'm adding it to my list

You may also enjoy How To Invent Everything[0], from the creator of SMBC Comics. The frame device is that it's a manual that comes with your time machine, only to be used if you get stranded. I thought it would be a fun flip-through but it's delightfully dense, with fun comments on when, where, and why you'd need want/need to invent something depending on "when" you get stranded in time.

0: https://www.howtoinventeverything.com/

Mild sidenote: How to Invent Everything is by Ryan North, the cat behind Dinosaur Comics; Saturday Morning Breakfast Cereal is done by Zach Weiner, a different person.

Milder sidenote: SMBC was created by Zach Weinersmith. Presumably his ancestors made the weiners.

I believe he changed his name when he married to incorporate his wife Kelly's

That might be the case! I haven't read SMBC regularly for a very long time, so if there was a name change in the past, i dunno, five years or something, I probably wouldn't have noticed!

Oof, you're correct! I totally mixed my comics up. Both are fantastic, pithy creators.

From the order page:

“To ensure that your future self is enjoying this book as we speak, simply click on one or more of the following links:”

Love it!

According to the article the patents were bought by Electrolux. It could be this was just to block this technology from being adopted.

No, it has been actually deployed and is commercially sold as heat recovery chiller.

The problem is an much lower efficiency than compression refrigerators, some of which could be regained by tuning the liquids used in the system. That is not a problem when you're working with waste heat though. (E.g. solar thermal, recovery from solar concentrated, cogeneration, geothermal.) The other problem is that it has to be perfectly leak checked or it does not work at all, where in compression leakage just reduces efficiency - and there's much less piping that has to be pressure sealed.

COP of maybe 1.3 for best designs is available, compared to say 5 of a top of the line screw chiller, 7 of a rotary chiller and 3 of very good heat pump. (Maybe COP could be pushed a bit higher with exotic liquids. But the economics of this endeavor are suspect. Current top efficiency liquids are water-ammonia/lithium bromide-water dual loop. It is not safe compared to HFCs.)

It starts making sense when the installation is building sized, because maintenance is cheap compared to an electric chiller.

I thought this is how RV (propane) refrigerators work? Or, am I confusing this with a different, but similar system?

Absorption refrigerators are commonly used in Recreational Vehicles (RVs), campers, and caravans because they can be powered with propane fuel, rather than electricity.

https://en.wikipedia.org/wiki/Absorption_refrigerator

You mean fridges that use propane as fuel or ones that use it as a freon?

As a fuel. And yes, it's the same principle.

No confusion, that's how the refrigerators work in our '81 VW camper and our much more modern Sprinter RV. Last I was in a position to know such things, many Amish use absorption fridges as well.

The patent is long expired. It has not seen widespread use because the efficiency is far below modern units. It does see some specialized use in situations where you have heat but not electricity--the conversion of heat to electricity is not a very efficient process, this can make it competitive.

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