# Sterling engines



## SPS-1 (Oct 21, 2008)

Red Squirrel said:


> Or how about a sterling engine generator?


You mean like this --- http://www.tesserasolar.com/north-america/technology.htm

Thats 25 kW ( when the sun is shining ) I don't see a size on the web site, but it looks pretty big. I don't think they are selling those yet, but it sure looks likes its going to cost a heck of a lot more that a 25 kW Generac generator.


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## Red Squirrel (Jun 29, 2009)

Yeah seen those before, but yeah think they're like half a million each or something. You can have multiple connect to a controller. They move with the sun and all. 

I could see big industrial places using these though.


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## nap (Dec 4, 2007)

Red Squirrel said:


> Yeah seen those before, but yeah think they're like half a million each or something. You can have multiple connect to a controller. They move with the sun and all.
> 
> I could see big industrial places using these though.


there are a couple installations out west with those (or some similar)


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## Daniel Holzman (Mar 10, 2009)

Solar cells range from 10 to 20 percent efficiency. The pictures posted showing parabolic reflectors are not Stirling engines, they are boiling water or pressurized water steam turbines, where the water is heated directly by sunlight. I believe the maximum efficiency on those types of installations is close to 30 percent, however they are complex because you need a mechanical system to force the reflectors to track the sun.

Stirling engines come in a variety of types. and in theory they can be more efficient than internal combustion engines. They have never become popular because you need a large engine to generate a relatively small amount of power, and they are relatively expensive per kilowatt to manufacture. They operate off the Stirling cycle, named after Robert Stirling I believe, inventor of the concept. Internal combustion engines run off the Carnot cycle, and jet engines (steam turbines) run off the Brayton cycle.


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## nap (Dec 4, 2007)

Daniel Holzman said:


> Solar cells range from 10 to 20 percent efficiency. The pictures posted showing parabolic reflectors are not Stirling engines, they are boiling water or pressurized water steam turbines, where the water is heated directly by sunlight. I believe the maximum efficiency on those types of installations is close to 30 percent, however they are complex because you need a mechanical system to force the reflectors to track the sun..


actually, the units I posted are Stirling engines.

http://billbrownclimatesolutions.blogspot.com/2009/01/solar-electric-power-and-renewable.html



> The SES Stirling Energy Systems SunCatcher is a 25-kilowatt (kW) Solar Power System consisting of a 38-foot diameter dish structure that supports 82 curved glass mirrors. The system is also called a heliostat because it tracks the movement of the sun throughout the day. The device labeled "Power Conversion Unit (PCU)" is the Stirling engine and its housing.



There are solar powered steam systems as well but the one I pictured is using Stirling engines.


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