In 1975 Wally Minto donated a design to the world. His unpatented wheel worked on a change of temperature as low as 3.5 degrees. Apparently if you handy with a welder you can build one too. You will need a selection of gasproof tanks of the same size and then weld them into a wheel shape. Each tank opposing each other should have a hollow tube connecting them together. Each tank should also have a low boiling point gas in them as well. Arrange on a axle so that only one or two tanks will me immersed in heated water (solar Perhaps) Operation The bottom gas tank is immersed in a tough of water solar heated or otherwise. The gas in the bottom is heated and the gas becomes lighter and flows to opposite tank where it cools down where it becomes heavier again. The heavier gas tank is then drawn down by gravity and the process begins again. The temp wheel rotates at slow speed but has high torque so step up gearing may give a higher speed output
For winter operation, a large heat collector buried under ground will supply the 3 and 1/2 degrees required to make it work during the winter.
In fact a bigger heat collector buried for winter use would be better along with a summer collector.
This Minto's motor will generate lots of power. If you need water or electricity this is the unit that could supply it.
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