The methods for producing cold utilizing heat source are called thermally activated cooling. They include adsorption1, absorption2 and desiccant cooling (solid desiccant cooling3 and liquid desiccant cooling4)
Absorption and adsorption are both used to provide thermal compression of refrigerant instead of mechanical compression. Some energy demand for refrigeration is thus shifted from electrical to thermal energy, and primary energy consumption is also reduced. Regeneration of sorption material can be achieved by using a low-grade heat source.
Absorption is the process in which a substance in one phase is incorporated into another substance of a different phase. Adsorption refers to the use of a solid for adhering ions and molecules of another substance onto its surface. The main differences between absorption and adsorption are in the nature of the sorbent (liquid/solid) and the sorption cycle (continuous/batch).
Desiccant cooling is another thermally activated technology; it works on the principle of incorporating desiccant dehumidification and the cooling unit, and its unique merit is that the sensible and latent heat can be processed separately. Desiccant cooling can be divided into solid desiccant and liquid desiccant cooling.
Trigeneration or CCHP (Combined Cooling, Heating and Power) is the simultaneous production of mechanical power (electricity), heating and/or cooling from one primary fuel, and is an extension of CHP (Combined Heat and Power, also defined as cogeneration) by coupling with thermally activated cooling technologies.
Within the concept of trigeneration, integrating a thermally driven chiller is necessary to produce cold water activated from ORC condensation heat sources at different temperatures levels, depending on working strategies.
Innovation in this type of system focuses on trigeneration applications within public buildings such as hospitals, office buildings etc.
Within BRICKER, CARTIF aims to select the most appropriate chillers taking into account the heat source levels and the particular boundary and climate conditions in each demo site: cooling demand of the demonstration buildings, the outlet condensation temperature of the cogeneration units, the interaction with solar fields, biomass plants and the existing conventional heat production systems in the buildings. One important point is that traditional cooling towers will not be covered by BRICKER for 2 reasons: health (legionella potential risks) and water savings. Therefore it is necessary to design a new generation of chillers with other condensation options such as dry coolers, adiabatic systems, condensation cascade systems, etc.