Variable buoyancy renewable power generator

A renewable power generating apparatus, comprising:

• a variable buoyancy module, designed to expand and contract as a material contained within the variable buoyancy module evaporates and condenses, displacing atmospheric air and thereby changing the buoyancy of the variable buoyancy module, while preventing leakage of the contained material, allowing efficient heat transfer from the atmosphere to the contained material and maintaining the material's pressure constant;
• the contained material sealed within the variable buoyancy module that is maintained at a constant pressure such that the contained material's boiling point is between the atmospheric temperatures of the lowest altitude at which the variable buoyancy module operates and the highest altitude at which the variable buoyancy module operates, such that heat transfer from the atmosphere evaporates the contained material at the lowest altitude and condenses the contained material at the highest altitude;
• a cable system traversing the highest and lowest altitudes, connected to the variable buoyancy module, counterbalanced such that the variable buoyancy module ascends when the contained material is evaporated and descends when the contained material is condensed;
• a lighter than air balloon connected above the cable system via a tether or directly connected above the variable buoyancy module via a tether;
• a power coupling unit connecting the cable system to an electrical generator such that movement of the cable system causes movement of the electrical generator and power generation;
• the electrical generator connected to the power coupling unit.