A power generation system for generating electricity using a steam turbine engine that yields high-pressure steam has been developed using a preferably non-toxic coolant circulating in a closed loop that passes through a rock and earth aquifer, for directly and/or indirectly condensing the low-pressure steam from the low-pressure side of the steam turbine into a liquid phase for re-circulation to the steam turbine, whereby the coolant acts to dissipate the heat from the low-pressure steam through the aquifer to the rock and earth encasing the aquifer. In one embodiment a containment shroud is employed to recycle condensing water utilized to condense the condensing vapor emitted from a steam condenser. In a second embodiment a sealed steam condenser is utilized through which the low-pressure steam passes, and water (or other suitable fluid) from an enclosed condensing water reservoir, through which the coolant is circulated, is employed to condense the low-pressure steam in the steam condenser. In yet another embodiment, the coolant is introduced directly into the steam condenser. In a further embodiment an intermediate refrigeration system pump is employed together with the coolant, for condensing the low-pressure steam.