Tri-generation systems: Energy policies, prime movers, cooling technologies, configurations and operation strategies

The serious energy supply problems along with the conventional resources depletion and the environmental conscience regarding global warming and climate change have urged the need for a complete change in the energy production, supply and consumption patterns. Therefore, the switch towards renewable energy resources including solar, biomass, wind and hydro-power in addition to the development of energy efficient technologies are two key factors to attain a secure and reliable energy sector and to mitigate the global warming problem. Tri-generation is one of the most promising technologies allowing the efficient simultaneous production of heat, coolth and power with potential technical, economic and environmental benefits. This paper provides a comprehensive review of the latest developments in the field of combined cooling, heating and power generation. Recent tri-generation supporting mechanisms, prime movers, cooling technologies, system configurations, fuels and renewable energy resources employed are presented and discussed. As the operation strategy is the critical factor governing the tri-generation system performance, the current work presents the recent strategies developed and implemented to optimize the system performance and improve its overall efficiency. While certain technologies employed in tri-generation systems as internal combustion engines, gas turbines and absorption cooling are well-established and have already found their way to the commercial market, other promising technologies including organic Rankine systems, fuel cells and liquid desiccant cooling, are still in the research and development phase with additional work needed to demonstrate their potential and reach commercialization. Based on the detailed and comprehensive review conducted, a summary with the main conclusions in addition to recommendations for future work are reported.