A system and process for generation of electrical power is provided. Electrical power is generated by a system including two integrated power cycles, a first power cycle utilizing water/steam as a working fluid and the second power cycle utilizing a fluid selected from the group consisting of molecular nitrogen, argon, a chemical compound having a boiling point of at most 65° C. at 0.101 MPa and a latent heat of vaporization of at least 350 kJ/kg, and a chemical compound having a boiling point of at most 65° C. at 0.101 MPa and a specific heat capacity as a liquid of at least 1.9 kJ/kg-° K as a working fluid. The working fluid of the second power cycle is expanded through a two-phase expander to produce power in the second power cycle, where the expanded working fluid of the second cycle has a temperature of at most 10° C.