Refrigeration systems incorporate an expansion process between the condenser and evaporator. Consider the case where Refrigerant 134a enters an expansion valve as a saturated liquid at 65°C with a mass flow rate of 6 kg/min and is steadily throttled to a pressure of 1 bar.

a. Determine the rate of entropy production for this process (in kW/K)

b. Determine the rate of exergy destruction for this process (kW). The dead state can be taken to be T0 = 25°C.

c. If the valve were replaced by a power-recovery turbine operating at steady state, determine the maximum theoretical power that could be developed (in kW)