Incredible Stirling Engines VIDEOS

Some can work on very low temperature differences (LTD):

• Making a LTD Stirling Engine (the video shows also how to build it!): here
• This one runs on the heat from a lamp! Here
  

A cruder design: here
Someone is using it to run a fan with the heat of a stove or candle... Refreshing, ah!? :D
But so far this question remains unanswered!

I have to investigate this... with the heat-wave that comes every summer in Europe, it could save quite a few KW/h ;)

The closest so far seems to be this one it should already work with temperature differences of 15 degrees: this means, if I put the bottom of the engine on a window, from inside the house, the difference between the cold air in the house and the hot sun outside (at summer) should be enough to make the fan spin.
And the more it spins the cooler the air around it becomes... damn, it could freeze my house! :}

I have to try!!

• A possible place to buy it is: http://www.stirlingengine.com/ecommerce/product.tcl?product_id=21
• or if you are a hardware nerd use the project in a previous post...
  
• Or a miniature version: here ... "My cold hands will barely run it on a cold day, but my wife, Hazle - the one with the hot hands - can rev it up to over 250 rpm in less than a minute!"
• This is also a good kit
• Here, the last of the page (not too cheap anyway)
• The whole description of how to build it, is here! (free)
• A very nice article is here, at the MAKE magazine, with a lot of links, and simple plans to build a Stirling engine with a few bucks ;)
• These are really cool, totally assembled, but expensive
  

Anoter nice discussion: here (power for a house).

A different kind of Stirling engine, cheap, good for educational purposes mostly: here.
And here, a similar engine, but very simple and DIY :)