Energy conversion method and system with enhanced heat engine

A method for converting a low grade energy to a high grade energy, comprising:

• increasing a pressure of a working gas in a cold side of a heat exchanger to a working pressure, wherein the working gas is at a cold side temperature;
• passing a fluid with a hot side temperature greater than the cold side temperature through a hot side of the heat exchanger, wherein the hot side and cold side are in heat transfer contact such that the passing causes a quantity of heat to be transferred to the working gas in the cold side;
• inputting the working gas in the cold side of the heat exchanger into a chamber having a pressure lower than the working pressure and a temperature lower than the cold side temperature;
• expanding the input working gas to convert heat in the input working gas into mechanical energy;
• and
• exporting a portion of the mechanical energy to a load outside the lower pressure, lower temperature chamber.

An energy conversion system, comprising:

• an outer tank defining an inner chamber with a cold side loop of a heat exchanger, wherein the outer tank is sealed to maintain a working gas in the cold side loop at a working pressure and is thermally insulated;
• an expander positioned within the inner chamber with an inlet for receiving the working gas after the working gas travels through the cold side loop, wherein the expander includes an expansion device for converting expansion by the received working gas into mechanical energy;
• a compressor positioned within the inner chamber adjacent the expander with an inlet linked to an outlet of the expander for receiving expanded working gas from the expander, wherein the compressor functions to compress the expanded working gas to about the working pressure and to discharge the compressed working gas into the cold side loop;
• and
• a heat source system having a hot side loop positioned within the cold side loop with a heat transfer device through which a hot fluid flows and having an exterior portion positioned outside the outer tank with means for transferring heat to the hot fluid.

An energy conversion mechanism, comprising:

• means for isolating a set of internal components from external pressures and temperatures;
• means for initially lowering the temperature of the set of internal components to create an artificial cold reservoir in the energy conversion mechanism;
• means for directing a working gas at a temperature higher than the temperature of the artificial cold reservoir through the set of internal component, wherein the working gas performs work on the internal components to produce mechanical energy and to lower the temperature of the working gas;
• means for converting the mechanical energy into an exportable form of energy;
• and
• means for exporting the exportable form of energy from the isolating means.

A method for starting an energy conversion system, comprising:

• providing an energy conversion device including an expander and a compressor, an isolation vessel enclosing the expander and the compressor, and a cold loop of a heat exchanger including an external wall, wherein the external wall is sealed to maintain a working pressure within the cold loop, the isolation vessel is constructed to isolate the expander and compressor from pressure and heat of a working gas in the cold loop;
• injecting a quantity of the working gas into the cold loop to create a starting pressure in the cold loop;
• importing energy into the energy conversion device to cool a chamber in the isolation vessel containing the expander to a cold reservoir temperature lower than the temperature of the working gas in the cold loop;
• operating the expander to receive a portion of the working gas from the cold loop and to allow the working gas to expand to generate mechanical energy;
• and
• using a portion of the generated mechanical energy to maintain the cold reservoir temperature.