High efficiency energy conversion

A method of extracting work from a metastable power cycle comprising:

• applying a source of thermal energy a substantially sealed variable volume container filled with a working fluid;
• allowing the substantially sealed container to dwell at a minimum volume for a time sufficient to convert the working fluid into a one or both of a high-pressure gas and a supercritical fluid via the applied thermal energy;
• expanding the substantially sealed container volume at a rate that outpaces a rate of condensation of the working fluid and in a manner sufficient to create one or more meta-stable thermodynamic states for the working fluid, wherein the expansion operation drives a reciprocating kinematic mechanism connected to the substantially sealed container to extract the work;
• allowing the substantially sealed container to dwell at a maximum volume for a time sufficient to cause the metastable thermodynamic state at the maximum volume to collapse back into an equilibrium thermodynamic state so as to condense a portion of the gas into a liquid phase and reduce pressure within the substantially sealed container;
• and
• compressing the substantially sealed container volume return the substantially sealed container to the minimum volume.

An energy conversion system comprising:

• an energy conversion mechanism that generates power through volumetric expansion of a working fluid substantially sealed within a variable volume container;
• a working fluid stored within the container;
• and
• a kinematic mechanism attached to the energy conversion mechanism and configured to provide volume expansion of the working fluid at a rate that outpaces a rate of condensation of the working fluid and in a manner sufficient to create one or more meta-stable thermodynamic states of the working fluid during an expansion period of a power cycle for the energy conversion system.