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Politecnico di Milano School of Industrial Engineering Course Energy Systems proff. S. Consonni, E. Martelli, M. Romano - Academic Year 2020-21 Written Exam of 15 July 2021 - Problems - Time: 2 hours PLEASE NOTICE 1) Exam is open book, but computers and cell phones are NOT allowed. Talking with colleagues and/or copying will lead to the immediate cancellation of the exam. 2) Answer clearly ONLY to the questions posed by the problem se ts. Even if correct, additional considerations and/or calculations will NOT be considered. 3) Fill this sheet with your name and return it together with your solutions. 4) Mark each sheet of the solution with your name and page number. 5) In addition to the points obtained for the solution of each problem, a bonus of max 3 points may be given based on whether the solution of each problem is complete, with clear details and explanations. Problem data depend on your person code according to the following two variables: X = sum of the numbers of your person code Y = sum of the first 4 numbers * sum of the last 4 numbers of your person code So, for instance, if the person code is 12345678  X = 36  Y = 10*26 = 260 INDICATE ON THE FIRST PAGE THE VALUES OF X AND Y DERIVING FROM YOUR PERSON CODE THAT YOU WILL USE IN THE EXAM Problem 1 (20 points) A steam cycle generates electricity for an industrial site. It features an oil-fired boiler and the following design and operating parameters:  Electric power generated by the steam turbine = X MW  Steam temperature at boiler outlet = 540 °C  Steam pressure at turbine inlet = 50+ Y/10 bar  Steam-side pressure drop of the boiler = 25% of the inlet feedwater pressure  Condensing pressure = 0.1 bar  Pumps hydraulic efficiency = 0.8  Mechanical*Electrical efficiency of the pump drivers (product of…