Energy tri-generation: Combined gas co-generation/solar cooling
Journal of Thermal and Environmental Engineering
The article presents an analysis of a tri-generation system using a solar energy as primary energy to provide a reliable alternative to minimize energy consumption in countries with a large solar field as the MENA region. At the University of Nancy, within the faculty of Sciences and Technologies, we are experimenting energy tri-generation through solar cooling of water for air-conditioning and heat/electricity cogeneration using gas fueled internal combustion engine. The technology used for refrigeration is combined thermal solar-adsorption cooling. The physical principle of an adsorption based refrigerating machine is in some respect similar to the operating principle of a conventional compression based refrigerating machine [1-4]. Both systems rely on a “condenser - expansion valve – evaporator” refrigerant cycle. However, the way the two systems achieve refrigerant’s vapor compression is quite different. While the conventional machine provides a “mechanical” compression of the refrigerant’s vapor (standard refrigerant), the sorption machine achieves rather a “thermal” compression of the refrigerant’s vapor (water) in two steps: in the first stage, the vapor issue from the evaporator is assimilated within a solid adsorbent (silica gel) by rejecting heat; in the second stage, this vapor is restituted back to the system loop at high pressure due to solar heat input through an intermediary fluid (water).