Here came up with the idea of a simple heat pump that will automatically start to work at a negative temperature outside the window. Such a pump can produce a little electricity, and then turn it into heat or spend it on some of your needs.
For assembly, you need a minimum amount of materials. Pipes or hoses will be needed, the coolant will be in them. It can be antifreeze, kerosene, gasoline, and generally non-freezing substances.
A hydraulic turbine or any other device that could turn mechanical energy into electrical energy.
You can make a water hammer installation and then connect a membrane with a solenoid and a permanent magnet to it. The membrane will vibrate, vibrations will be transmitted to the core of the solenoid and thus induction currents will occur.
The circuit consists of two coils, one upper and one lower. It can be radiators of batteries, various snakes, however you can make a coil yourself from a pipe or hose.
The lower radiator will be located underground at great depths, best if it is a well with spring water. As you know, the underground temperature is always positive, even in winter. If you look at the springs with spring water, then it does not freeze even on the surface.
An artist out of me, but I think it will be clear)
The upper radiator will be located on the surface of the earth and it is best that a sun dome be placed above it.
Both radiators are interconnected by pipes in a circle.
How does it all work? As soon as winter comes and the temperature drops below -1, fluid begins to circulate in the system. Below it will heat up, expand, become lighter and move up. This is a free energy that can be "removed".
About -1, I said figuratively, formally, if there is +5 underground, and +4 on the surface, the system will also work.Of course, the stronger the difference in temperature, the more energy will be released.
Such systems can be made many or one large. This can significantly reduce heating costs. I will try to assemble such a structure in the village in the spring.