Working Fluid Selection for Organic Rankine Cycle and Other Related Cycles

• Other Authors: Imre, Attila R. (Editor)
• Format: Electronic Book Chapter
• Language: English
• Published: Basel, Switzerland MDPI - Multidisciplinary Digital Publishing Institute 2020
• Subjects: History of engineering & technology; adiabatic expansion; isentropic expansion; T-s diagram; working fluid classification; optimization; single-screw expander; vapor-liquid two-phase expansion; thermal efficiency; net work output; heat exchange load of condenser; cis-butene; HFO-1234ze(E); ORC working fluids; temperature-entropy saturation curve; saturation properties; wet and dry fluids; ideal-gas heat capacity; Rankine cycle; ORC; biomass; fluid mixtures; hydrocarbons; working fluid; selection method; volumetric expander; thermodynamic analysis; wet zeotropic mixture; single screw expander; organic Rankine cycle; R441A; R436B; R432A; molecular degree of freedom
• Online Access: DOAB: download the publication; DOAB: description of the publication

The world's energy demand is still growing, partly due to the rising population, partly to increasing personal needs. This growing demand has to be met without increasing (or preferably, by decreasing) the environmental impact. One of the ways to do so is the use of existing low-temperature heat sources for producing electricity, such as using power plants based on the organic Rankine cycle (ORC) . In ORC power plants, instead of the traditional steam, the vapor of organic materials (with low boiling points) is used to turn heat to work and subsequently to electricity. These units are usually less efficient than steam-based plants; therefore, they should be optimized to be technically and economically feasible. The selection of working fluid for a given heat source is crucial; a particular working fluid might be suitable to harvest energy from a 90 ℃ geothermal well but would show disappointing performance for well with a 80 ℃ head temperature. The ORC working fluid for a given heat source is usually selected from a handful of existing fluids by trial-and-error methods; in this collection, we demonstrate a more systematic method based on physical and chemical criteria.