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A solar-thermal plant is used to produce power. A molten salttransfers heat to a non-ideal Rankine cycle to produce electricityfrom a turbine. The molten salt has an average temperature of 800oC when transferring heat to the boiler in the Rankine cycle. Thecondenser for the power cycle exchanges heats with water in a riverthat is at 20 oC. The steam flow rate through the cycle is 10 kg/s.The inlet of the boiler is at 9 MPa absolute and steam leaves theboiler at 9 MPa absolute and 600 oC. The exit of the turbineoperates is at 20 kPa absolute and has a quality of 95%. The exitof the condenser is at 20 kPa absolute and is a saturatedliquid.

Draw a diagram of the Rankine cycle. Include all the unitoperations (pieces of equipment). Show the direction of flow andwhere heat and work enters and leaves the cycle. Number the streamsin the cycle. State proper assumptions.

1. What is the power consumption for the pump (in MW), the powerproduced by the turbine (in MW), the thermal efficiency of thecycle?

2. What is the maximum thermal efficiency that a heat engine canhave operating between the temperatures of the heat source moltensalt and heat sink river? Why should the efficiency calculatedwould be less than this maximum? List at least four places in thecycle that contribute to the real plant having a lower thermalefficiency than the maximum.