Tesla's Ambient Heat Engine Theory - Right or Wrong ?

[DaS Energy]

Question?  The engine fuel source being compressed air, where does the energy come from to compress the air?

[memoryman]

Question?  The engine fuel source being compressed air, where does the energy come from to compress the air?

Whatever drives the compressor (for example a standard shop air compressor) supplies the energy, usually in mechanical form (electric motor for example).

[Tom Booth]

Tom, compressing gas partially converts energy from the compression process to heat;

I agree, but I don't believe that that is all that happens. That is, not all the heat comes from the energy of the compression process, (work done on the gas). At least some of the heat released is due to the gas being restricted in a smaller space so it gives up some of its internal kinetic energy (heat).

That is just my opinion I suppose but the conclusion seems unavoidable to me.

[Tom Booth]

Question?  The engine fuel source being compressed air, where does the energy come from to compress the air?

If you are referring to Tesla's "Self Acting"engine, the energy to run the engine is derived from ambient heat or indirect Solar Energy.

The fuel source is not compressed air (not the pressure of compressed air) as such but the heat driven off by compressing the air. The fuel is the heat.

But primarily the cold produced by throwing heat away is what creates the temperature difference to run the engine. It is a kind of heat engine. The "fuel" is heat, ambient heat, not compressed air. Compressing the air is just a means of establishing a temperature differential.

You might say then that the fuel is not heat so much as the cold produced by removing the heat which gives the freely available ambient heat something to flow into. once established the engine intercepts that flow.

I look at it more or less like a kind of siphoning action. In this case Heat is being siphoned out of the air not by a heat sink but by converting the heat into electricity which leaves a "cold hole" for more heat to flow into.

[Tom Booth]

In other words, the whole idea is to first establish a "cold hole" for the ambient heat to flow into. As Tesla wrote:

"Could we produce artificially such a "sink" for the energy of the ambient medium to flow in? ... can we produce cold in a given portion of the space and cause the heat to flow in continually?"

Once a flow is established a heat engine can be used to intercept it. Tesla reasoned that since the heat engine converts heat into another form of energy, such as electricity "there will be less to pump out than flows in, or, in other words, less energy will be needed to maintain the initial condition than is developed by the fall, and this is to say that some energy will be gained from the medium." So the excess unconverted heat needs to be dumped somewhere. The ideal place to dump it as far as possible is back into the heat engine thus: "What is not converted in flowing down can just be raised up with its own energy, and what is converted is clear gain."