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POWER PRODUCTION FROM RENEWABLE ENERGY AY 2015-16 12th February 2016 Prof. Silva and Manzolini Time: 1,5 hours Instructions for the examination: 1) Clearly indicate your name on all the sheets you will deliver. 2) The score refers to exercises done in a comprehensive manner with exact numerical results. Numerical results correct but not accompa- nied by explanations will not be taken into account. The final score will be normalized according to the average results. 3) Answer briefly and clearly only to the asked questions. Calculations and explanations which do not respond to the questions will not be considered for evaluation even if correct. 4) Talking with colleagues and / or cheating will cause the cancellation of the exam. 5) All the needed data for the resolution of exercises lies on this paper. It’s NOT ALLOWED to use material other than this (e.g. books, clip- board etc.) Exercise 1 (16 points) It should be evaluated the installation of a PV plant for residential applications . The PV plant is installed on the roof of a house ( 5 x 7 m), the azimuth of the house is 30° (the azimuth is determined starting from south direction, positive counterclock -wise) and the tilt of the roof is 30° . Assuming the PV module and i nverter characteristics reported in the f ollowing table, determine the nominal power installed (AC), the number of i n- verters discussing the results (it’s not necessary to check the conditions at minimum and maximum te mpera- ture). (5 points) PV modules Inverter Power @STC 320 W Power input in CC 2650 W Open circuit voltage @STC 64.8 V Maximum voltage 600V Short circuit current @STC 6.24 A Power point operating voltage 260-500 V Voltage at MPPT@STC 54.7 V Power output in AC 2500 W Voltage coefficient –176,6 mV / °C Current coefficient 3.5 mA/°C…