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As the adoption of solar hybrid systems continues to rise due to their potential to compensate for the fluctuation of solar irradiation, it becomes imperative to accurately evaluate their performance, considering the variation of off-design conditions. This paper introduces a detailed analysis method for evaluating the annual performance of a solar-MGT system under transient boundary conditions for a whole-year operation range. A hybrid system of a micro gas turbine, recuperator, and solar dish is considered, and an off-design simulation model is developed and verified with available experimental results. Two different configurations for a recuperated cycle are considered, and simulations are conducted for a test case in Pretoria, SA. The results for Jun.21 and Dec.21 as low and high solar energy days are reported with more details to compare the configurations and demonstrate the effect of ambient temperature on the heat loss of the solar receiver and the overall performance of the system. The alternative configuration reduces heat loss with a lower temperature receiver but has higher fuel consumption compared to the conventional configuration. Operating strategies for different hours of operation from 1 h to 24 h per day are simulated for 365 days, based on real meteorological data, and compared with the operating in solar available hours. It is shown that the whole-year simulation of the system considering the variation of boundary conditions can change the estimation of fuel consumption by 25 %., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Seyedvahid Hosseini reports financial support was provided by 10.13039/501100000780European Commission Marie Sklodowska-Curie Actions. Hossein Madani reports financial support was provided by 10.13039/100014013UK Research and Innovation. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

The mottos of scholars of environmental protection movement have turned to "think globally, act locally". For this reason, environmental non-governmental organizations (ENGOs) that have received significant attention in all societies are operational approaches towards protecting the environment and realizing sustainable development. Analysis of the nature of ENGOs' activities reveals that the main function of ENGOs is "participatory, voluntary and supportive". This function can be facilitated through the development of communication of these organizations with governments for the exchange of ideas in order to improve the implementation of developmental projects and approve new environmental laws. Given the fact that ENGOs act as civil societies in the public domain, it can be said that the operational environment for ENGOs is a special political space that should be provided through governments' assistance and support. That is why the present study investigates the relationship between Iranian ENGOs and government agencies. To this end, in-depth interviews are conducted with environmental experts in environmental protection organization and forests, range and watershed management organization in Iran and members and managers of Iranian ENGOs. Also, a questioner is designed and then, completed by managers of Iranian ENGOs. It is found that there is too little communication between Iranian ENGOs and governmental agencies. ENGOs don't discuss various environmental issues with government as advocators. Finally, the principles governing the relationship between NGOs and government is also discussed. Research findings indicate that the type of regime and maturity of NGOs affect the relationship between ENGOs and government agencies., (© 2019 Published by Elsevier Ltd.)