A system (10) includes a fluid with components that evaporate at different temperatures, a condenser (12) with an inlet (22) and an outlet (24), a pump (14) with an outlet (28) and with an inlet (26) connected to the outlet (24) of the condenser (12), and an evaporator (16). The evaporator (16) includes an inlet (30) connected to the outlet (28) of the pump (14), an outlet (31), evaporating tubes (38), pool boiling tubes (42), and a fluid distribution system (33) for spraying the fluid over the evaporating tubes (38). The system (10) further includes a turbine (18) with an inlet (44) connected to the outlet (31) of the evaporator (16), an outlet (48) connected to the inlet (22) of the condenser (12), and a drive shaft (46). A generator (20) is connected to the drive shaft (46) of the turbine (18).