In Egypt, surveying the industrial sectors revealed that in the last few years the industrial process heat (IPH) consumed more than 60% of the annual industrial energy demand, of which about 50% is in the temperature range from 80 to 150°C. Among different renewable energy resources, it is found that solar thermal technologies, especially parabolic trough concentrators (PTC) are more convenient for the IPH applications. Thus, the present work deals with studying the main design and performance characteristics that enable the local manufacturing of a PTC for IPH applications in the range of 80 to 150°C in Egypt. It includes theoretical and experimental parts. The theoretical part was conducted using a specially developed computer program based on the energy balance equations of each component of PTC. The experimental part was carried out on a test rig designed and constructed using mainly local manufacturing capabilities. Effects of concentration ratio, radiation, inlet temperature and mass flow rate of the heat transfer fluid, glass envelope diameter and top thermal insulation on the theoretical and experimental performance of PTC are graphically reported. Finally, a brief discussion of the local manufacturing possibilities as well as some identified barriers that can hinder promotion of the technology in a very suitable and huge market like Egypt is presented in this paper.
Solar thermal central receivers for industrial process heat generation: user views and recommendations for commercialization
