Selection of High-Performance Working Fluid for a Solar-Geothermal Absorption Cooling System and Techno-Economic Study in the Northern Mexican Conditions
Abstract
The global energy demand is increasing at alarming rates. This increase is expected to be twice as big in developed countries like Mexico, and until 2040, most of this energy will still be coming from fossil fuels, which generate pollution and global warming, increasing even more the energy demand and creating a vicious circle. Absorption systems represent a possibility to contribute to the reduction of fossil fuels consumption and CO2 emissions. These systems can run on renewable energies like solar energy, however, they possess until now high initial investment costs. Two studied methods to improve these system’s effectiveness are new refrigerants and heat sink sources. The present article proposes the study of a small-capacity geothermally cooled absorption system in the Monterrey city (Mexico) climate conditions comparing the two more conventional working fluids (NH3-H2O and H2O-LiBr) and an innovative working fluid (NH3-LiNO3). The work is divided into three parts: The first section studies the specific climatic conditions of Monterrey and their impact on the operating temperatures in the system. The second section compares the thermodynamic cycles of the three proposed working fluids in these conditions. Finally, the dimensioning of the components of the system and an economic viability study for the three working pairs is presented to see if it is cost-effective.