ES 15 01 2025 theoretical test

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POWER PRODUCTION FROM RENEWABLE ENERGY AY 2023-24 15th January 2025 Prof. Andrea Giostri Time: 1 hour NAME and SURNAME:.................................................................................................................................................. COURSE and CFU:............................................TYPE (Complete or Theory only):................................................. Optional Teamwork grade:..............................Previous Practical text grade(if Theory only) : ........................... Instructions for the examination: 1) Clearly indicate your name on all the sheets you will deliver. 2) Give a synthetic and clear answer to as many questions as possible. The final score will be normalized according to the average results. 3) Talk with colleagues and / or cheating will cause the cancellation of the exam. OPEN QUESTIONS (points 18) 1. For All Students Draw the electric scheme of a PV cell and describe the meaning of each represented component. Draw and explain the Current-Voltage characteristic curve of the cell and define the fill-factor parameter. 2b. For All students Draw the velocity triangles of a blade of a horizontal axis wind turbine (large scale). Show the forces acting on the blade and the projections in the axial and tangential direction. Discuss the characteristics of the blade to maximise its aerodynamic efficiency. MULTIPLE-CHOICE QUESTIONS (points 12) Answer to the following 15 questions. Select the box with correct answer (0.8 points if correct, -0.3 points if wrong). Consider an installed PV module (without shadow): “oc”Open circuit “sc” Short circuit Tamb  Ambient temperature A decrease of solar radiation causes a reduction of Isc and a slight Voc increase A Tamb increase involves a reduction of both power…