They're playing fast and loose with physics. Stirling engines produce heat through frictional losses. The only way it's going to produce *cold* is through using that Stirling engine to induce some form of evaporative cooling by compression / expansion, similar to a modern refrigeration system.
While being a very interesting process and making for great little toys, unfortunately the low power output of stirling engines means any real and worthwhile power output would take an impractically sized ( and cost) unit.
Even getting 1 Kw out of these things would take a Very large unit and either a wasteful heat source or a vey big collector of low density heat.
Either way, extremely difficult to make worth while and more importantly, cost effective.
While being a very interesting process and making for great little toys, unfortunately the low power output of stirling engines means any real and worthwhile power output would take an impractically sized ( and cost) unit.
Even getting 1 Kw out of these things would take a Very large unit and either a wasteful heat source or a vey big collector of low density heat.
Either way, extremely difficult to make worth while and more importantly, cost effective.Yes, Stirling machines that use atmosphere-pressure air as the working fluid are large. But, if you use pressurized Hydrogen or Helium as the working fluid, and allow the machine to run fairly fast, they can be quite compact. There is a Stirling solar power station in, i think, Arizona that has 50 KW Stirling engines mounted on each heliostat - by the hundreds. They are quite compact.
Sunpower built some really cutting-edge free-piston Stirling engines in the 1970's that were very compact. But, they didn't deal with the metallurgy properly, their engines had VERY short life.
Jon
On 29 September 2011, Stirling Energy Systems filed for Chapter 7 bankruptcy as the Stirling dish technology could not compete against the falling costs of solar photovoltaics, according to media reports.
Just as 200 years ago Stirling engines lost out to steam and electric motors it appears history repeated itself with Stirling engines once again just not being cost effective enough.
Waffle Waffle Waffle .... With things like sterling engines, once they are installed in working applications ( other than space which is irrelevant) they will just be interesting tech that isn't practical in the modern age.
According to the link you posted the Sterling engines in submarines need a supply of liquid oxygen to work and a large body of water to work. While this might work for submarines wee are not seeing it be used in ships, cars, airplanes or in factories. I don”t think anyone has said Sterling engines do. Not work, we are just saying there are very few applications for them. Clearly you he need for liquid oxygen limits there application.
According to the link you posted the Sterling engines in submarines need a supply of liquid oxygen to work and a large body of water to work. While this might work for submarines wee are not seeing it be used in ships, cars, airplanes or in factories. I don”t think anyone has said Sterling engines do. Not work, we are just saying there are very few applications for them. Clearly you he need for liquid oxygen limits there application.The idea of this submarine is to run underwater with no supply from the surface. So, if you can't suck air from the surface with a snorkel, you have to have a tank of oxidizer to burn your fuel with. That is why they need liquid Oxygen. It is just like a rocket, no air in outer space, so you have to carry some oxidizer in tanks.
No other Stirling engine needs this, they just need a heat source.
Jon
You really are full of something aren't you. You are being negative here and like your climate waffle anti science you spout on the modern use of Stirling Engines denying Science yet again.
Clearly the Swedish should have employed you to tell them where they went wrong on their Submarines https://en.wikipedia.org/wiki/Gotland-class_submarine before they snuck up on the Yanks in war games using your non credible device.
"It takes 100% of stack-emitted waste energy, or solar thermal ... and converts that for 40-50% [efficiency]."
Some more reading here. The Sub in question has a hybrid drive system. The Stirling Engine / Generator set still need Oxygen while submerged to Burn Fuel. The principal advantage of the Stirling design is it doesn't make anywhere near the noise of more conventional Diesel/Electric subs while submerged.
https://en.wikipedia.org/wiki/Air-independent_propulsion
The idea of this submarine is to run underwater with no supply from the surface. So, if you can't suck air from the surface with a snorkel, you have to have a tank of oxidizer to burn your fuel with. That is why they need liquid Oxygen. It is just like a rocket, no air in outer space, so you have to carry some oxidizer in tanks.
No other Stirling engine needs this, they just need a heat source.
Jon
The idea of this submarine is to run underwater with no supply from the surface. So, if you can't suck air from the surface with a snorkel, you have to have a tank of oxidizer to burn your fuel with. That is why they need liquid Oxygen. It is just like a rocket, no air in outer space, so you have to carry some oxidizer in tanks.
No other Stirling engine needs this, they just need a heat source.
JonYup. The goal is to stay under water for a long time so you need to bring with you both oxidiser and fuel. You would need that for a diesel motor as well.
There are defiantly one off unique applications for Sterling engines and this appears to be one of them. I know of a couple of unique novel applications for Sterling engines.
Would it be safe to say the reason Sterling Engines are not is wide spread use is we have found other technologies over the past 150 years which are less expensive and provide far more power?
The idea of this submarine is to run underwater with no supply from the surface. So, if you can't suck air from the surface with a snorkel, you have to have a tank of oxidizer to burn your fuel with. That is why they need liquid Oxygen. It is just like a rocket, no air in outer space, so you have to carry some oxidizer in tanks.
No other Stirling engine needs this, they just need a heat source.
JonYup. The goal is to stay under water for a long time so you need to bring with you both oxidiser and fuel. You would need that for a diesel motor as well.
Correct me if wrong but would just the liquid O2 run the Sterling engine without the need to burn it? Wouldn't the temperature differential between liquid O2 and seawater be enough to power the engine?
It was my understanding the liquid oxygen is used as a coolant for the Sterling Engine. Maybe it is used as both an oxidizer and a coolant?
Guess what I'm not understanding is why an oxidizer is needed with a Sterling engine.
Help me out here, what am I missing.
Correct me if wrong but would just the liquid O2 run the Sterling engine without the need to burn it? Wouldn't the temperature differential between liquid O2 and seawater be enough to power the engine?
In theory at least, but it would be insignificant amount of energy compared to the chemical energy you can get by burning it.