Energy, Vol.83, 474-485, 2015
Experimental characterisation of a solar parabolic trough collector used in a micro-CHP (micro-cogeneration) system with direct steam generation
An experimental campaign has been conducted on a solar parabolic trough collector feeding a micro-CHP system (micro-cogeneration). The originality of the solar field is the DSG (direct steam generation) using a two axis tracker and a small size (46.5 m(2)) collector. The first step of the characterisation of the CHP (Combined Heat and Power) system is the study of the solar field under direct steam generation. Thermal performances under sunny and cloudy conditions are presented. On the studied sunny day, the system produces saturated steam during 8 h with a quality higher than 0.6 for a flow rate of 33 kg/h. Thanks to the two axis tracker, the output power and steam production are stable throughout the day. The dynamics of the collectors observed on a cloudy day under two-phase flow, show strong variations of the output power and flow rate that can even cease with clouds. Next, the impact of working and outdoor conditions is presented. Finally, the thermal efficiency of the collector is measured with steam. Reached efficiency is consistent with the literature for small size systems with direct steam generation. The collector performances are suitable for the coupling with the steam engine. Thus, the first results obtained with the engine are presented. (C) 2015 Elsevier Ltd. All rights reserved.
Keywords:Solar thermal energy;Small-scale system;Parabolic trough collector;Direct steam generation;Experimentation