01 13 06 2022 TEM Exercises solutions

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Department of Energy Politecnico di Milano Author Emanuela Colombo Pag.1 of 18 Date 27/06/2022 Milan, 25th May 2022 Exam –Thermoeconomics and Energy Modelling 13-06-2022 Total score: 21 points (exercise 1 roughly 2/3 of the total) Exercise 1. The concentrated solar power plant depicted in Figure 1 works with a water steam Rankine cycle. This is a regenerative cycle. A portion of the s team exiting from the expansion Turbine enters a regenerative Heat Exchanger (mixing type) which lays in between the two feeding pumps. The solar radiation captured by solar field is equal to 942.1 MWth while the net electric power produced by the plant is equal to 39.1 MWel. The heat released by the condenser is discharged in the environment without any additional cost. FIGURE 1: PLANT SCHEME Table 1 State Description Exergy [MW] 0 Solar radiation 942.1 1 Outlet solar field 109.5 2 Inlet HP turbine 69.9 Whp Power output HP turbine 28.4 3 Outlet HP turbine 41.0 4 Inlet LP turbine 59.9 Wlp Power output LP turbine 39.1 5 Outlet LP turbine 4.7 SOLAR FIELDHeat Exchanger 1 HP turbine LP turbine WHP WLP Feed pump II Feed pump I Condenser 1 3 2 4 5 10 9 8 6 7 Wp1 Wp2 110 Heat Exchanger 2 Department of Energy Politecnico di Milano Author Emanuela Colombo Pag.2 of 18 Date 27/06/2022 6 Outlet condenser 0.1 Wp1 Power supply Feedpump 1 0.1 7 Outlet Feedpump 1 0.1 8 Inlet Feedpump 2 0.9 Wp2 Power supply Feedpump 2 0.8 9 Outlet Feedpump 2 1.5 10 Bleeding 10.6 11 Condenser discharge 0 Consider T 0 and P0 to be respectively 298.15 K and 1 bar and the following table as additional data. With reference to the data provided, it is required to: a. Write the exergy balance computing exergy destruction for the whole plant . Check the result with the summation of the destructions for each component provided in…