Theoretical test 2024119

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SOLAR AND BIOMASS POWER GENERATION AY 2023-24 19th January 2024 Prof. Marco Binotti Time: 40 minutes Instructions for the examination: 1) Clearly indicate your surname and name on all the sheets you will deliver. 2) The final score can be normalized according to the average results. 3) Answer briefly and clearly only to the asked questions. 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) It is NOT ALLOWED to use material other than this (e.g. books, clipboard etc.). Each answer shall fit in one A4 page Question A) PV: Explain the function of the by-pass diodes in a PV panel and show how the I-V curve changes in case of shadowing of one cell (e.g. 50% shadowing) in a panel with and without by-pass diodes. Question B) CSP: Please write and discuss how the optical efficiency of a parabolic trough (PT) collector changes in off-design con- ditions and draw a plot that qualitatively shows the variation of the efficiency as function of the most relevant param- eter. Explain and justify each loss term. Question C) Biomass: Draw the biogas production of a landfill. Discuss the design options of a biogas plant producing electricity using the abovementioned landfill (time of collecting the biogas, number of collecting pipes, internal combustion engine num- bers and size)