Building a Solar-Powered Stirling Engine

AI Thread Summary
The discussion centers on the feasibility of using solar heat to power a Stirling engine, with a focus on the solar flux of approximately 1350 watts/m2. Participants clarify that this measurement refers to light energy that could be converted to heat at 100% efficiency. The efficiency of traditional solar panels is noted to be around 10%, with some advanced cells achieving up to 15.9%. While Stirling engines are highly efficient heat engines, their practical power output is limited, making them less viable for driving electric generators. Overall, the conversation highlights the challenges and considerations in comparing Stirling engines to solar panels for energy conversion.
RKD89
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Hi Guys
I m trying to make a Stirling engine power by solar heat.
Somewhere I found out that the solar flux available on Earth is abt 1350watts/m2

Is this heat energy only or "heat & light " combined??


I m trying to find out if my soar engine will be better than traditional solar cells??

What is the energy conversion rate for solar panels/m2?
 
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A Stirling engine is one of the most efficient heat engines known. It is doubtful if a solar panel (notoriously inefficient) would be anywhere near as good at converting heat directly into mechanical movement.

On the other hand, if you intend to run (say) an electric generator from your engine, forget it. The power developed by a model Stirling is amazingly low - it can barely keep itself running against friction.

Here's a vid of my own Stirling.

http://www.youtube.com/watch?v=GtTz4X7Mi64"
 
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RKD89 said:
Hi Guys
I m trying to make a Stirling engine power by solar heat.
Somewhere I found out that the solar flux available on Earth is abt 1350watts/m2

Is this heat energy only or "heat & light " combined??


I m trying to find out if my soar engine will be better than traditional solar cells??

What is the energy conversion rate for solar panels/m2?
The 1.35 kW/m2 refers to the light and would produce that thermal power if it could be converted to heat at 100% efficiency.

One could use 10% as a reasonable estimate of the efficiency of PVs.
http://www.examiner.com/green-techn...ic-efficiency-record-using-low-cost-materials

World's Highest Photovoltaic Energy Conversion Efficiency Among Monolithically Integrated Flexible Solar Cells = 15.9 %
http://www.azonano.com/news.asp?newsID=16822

There are apparently more efficient PV cells in the works.
http://www.technologyreview.com/Energy/18910/
 
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