16 February 2022 with results

Pagina 1

SOLAR AND BIOMASS POWER GENERATION AY 2021-22 16th February 2022 Prof. Giampaolo Manzolini Time: 100 minutes Instructions for the examination: 1) Clearly indicate your surname and 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 accompanied by expla- nations will not be taken into account. The final score can 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 is NOT ALLOWED to use material other than this (e.g. books, clipboard etc.). 6) Not all the provided inputs are necessary for the problem solving CSP exercise (17 points) Question A (5 points): It is required to size a concentrated solar power plant based on parabolic trough collectors using Molten salts as Heat Transfer Fluid (Tmin 300 - Tmax 565°C) and steam cycle to convert the thermal energy into electricity. The solar plant characteristics are reported in the table below: Power cycle net power output 125 MW Piping thermal losses 4 MW Power cycle second law efficiency 65% Specific solar field thermal losses (power referred to the aperture area) 75 W/m2 Ambient temperature 25 °C Design DNI 950 W/m 2 Solar multiple 2 Mirror Reflectivity 95% Receiver Absorptivity 94% Glass envelope transmissivity 95% Intercept factor 95% Question B (5 points): Determine the yearly energy production and equivalent operating hours considering the assumptions re- ported in the…