TY - JOUR
T1 - A computational drop-in assessment of hydrofluoroethers in Organic Rankine Cycles
AU - Jovell, Daniel
AU - Gonzalez-Olmos, Rafael
AU - Llovell, Fèlix
N1 - Publisher Copyright:
© 2022 The Authors
PY - 2022/9/1
Y1 - 2022/9/1
N2 - Organic Rankine Cycles (ORCs) are experiencing a growing interest due to their ability to generate electricity from residual low waste heat sources. HFC-245fa is a representative working fluid for ORC applications, but it has recently been phased-out in new equipment because of its high global warming potential (GWP). In this work, the soft-SAFT molecular-based equation of state is used to evaluate the capacity of nine promising low-GWP hydrofluoroethers (HFEs) as alternative working fluids in ORC applications using different key performance indicators focused on energy efficiency and service fluids consumption. The thermodynamic model has been employed to characterize these fluids by describing saturated densities, vapor pressure, surface tension, temperature-enthalpy, and temperature-entropy diagrams, including further validation with binary mixtures. Then, based on technical criteria focused on the thermal efficiency and working and service fluids consumption, the soft-SAFT model has been used to conduct a feasibility study of HFEs as direct substitutes for HFC-245fa in such applications. Although pure fluids can not reach the same efficiency as the benchmark, HFE-356mmz, HFE-7000, and HFE-7100 appear as promising replacements, capable of approaching system requirements operating at low pressure with low cooling water and heating fluid flow rates, while exhibiting lower GWP values.
AB - Organic Rankine Cycles (ORCs) are experiencing a growing interest due to their ability to generate electricity from residual low waste heat sources. HFC-245fa is a representative working fluid for ORC applications, but it has recently been phased-out in new equipment because of its high global warming potential (GWP). In this work, the soft-SAFT molecular-based equation of state is used to evaluate the capacity of nine promising low-GWP hydrofluoroethers (HFEs) as alternative working fluids in ORC applications using different key performance indicators focused on energy efficiency and service fluids consumption. The thermodynamic model has been employed to characterize these fluids by describing saturated densities, vapor pressure, surface tension, temperature-enthalpy, and temperature-entropy diagrams, including further validation with binary mixtures. Then, based on technical criteria focused on the thermal efficiency and working and service fluids consumption, the soft-SAFT model has been used to conduct a feasibility study of HFEs as direct substitutes for HFC-245fa in such applications. Although pure fluids can not reach the same efficiency as the benchmark, HFE-356mmz, HFE-7000, and HFE-7100 appear as promising replacements, capable of approaching system requirements operating at low pressure with low cooling water and heating fluid flow rates, while exhibiting lower GWP values.
KW - Drop-in replacement
KW - Energy consumption
KW - Hydrofluoroethers
KW - Organic Rankine Cycle
KW - Polar soft-SAFT
KW - Thermal efficiency
UR - http://www.scopus.com/inward/record.url?scp=85130937862&partnerID=8YFLogxK
UR - https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=pure_univeritat_ramon_llull&SrcAuth=WosAPI&KeyUT=WOS:000808544700012&DestLinkType=FullRecord&DestApp=WOS_CPL
UR - http://hdl.handle.net/20.500.14342/4444
U2 - 10.1016/j.energy.2022.124319
DO - 10.1016/j.energy.2022.124319
M3 - Article
AN - SCOPUS:85130937862
SN - 0360-5442
VL - 254
JO - Energy
JF - Energy
M1 - 124319
ER -