Energy, Exergy, and Environmental (3E) Analysis of Hydrocarbons as Low GWP Alternatives to R134a in Vapor Compression Refrigeration Configurations

Abstract

The phase-down of hydrofluorocarbons and substitution with low global warming potential values are consequences of the awareness about the environmental impacts of greenhouse gases. This theoretical study evaluated the energy and exergy performances and the environmental impact of three vapor compression system configurations operating with the hydrocarbons R290, R600a, and R1270 as alternatives to R134a. The refrigeration cycle configurations investigated in this study include a single-stage cycle, a cycle equipped with an internal heat exchanger, and a two-stage cycle with vapor injection. According to the results, the alternative hydrocarbon refrigerants could provide comparable system performance to R134a. The analysis results also revealed that using an internal heat exchanger or a flash tank vapor injection could improve the system’s efficiency while decreasing the heating capacity. The most efficient configuration was the two-stage refrigeration cycle with vapor injection, as revealed by the exergy analysis. The environmental impact analysis indicated that the utilization of environmentally-friendly refrigerants and improving the refrigeration system’s efficiency could mitigate equivalent CO2 emissions significantly. The utilization of hydrocarbons reduced the carbon footprint by 50%, while a 1% to 8% reduction could be achieved using the internal heat exchanger and flash tank vapor injection.

Investigation of the Interactions between Refrigerant, Flowsheet, and Compressor in Residential Heat Pumps

“…Adjusting the flowsheet can improve thermodynamic performance by reducing overall cycle irreversibilities. [6][7][8] In the literature, many flowsheets have been investigated. [6][7][8][9][10][11][12][13][14] Domanski et al [15] studied the simple cycle, an internal heat exchanger cycle, a vapor injection with a flash tank cycle, and a work recovery cycle.…”

“…[6][7][8] In the literature, many flowsheets have been investigated. [6][7][8][9][10][11][12][13][14] Domanski et al [15] studied the simple cycle, an internal heat exchanger cycle, a vapor injection with a flash tank cycle, and a work recovery cycle. They optimized the fluid parameters of a hypothetical pure refrigerant to evaluate the optimal Pareto curve.…”

“…However, current refrigerant assessment and selection methods usually only consider a fixed flowsheet, one case for the heat source and sink conditions, or constant compressor efficiencies. [25][26][27][28][29][30] Only a few studies cover the influence of the flowsheet [8,16,[31][32][33][34][35] or the conditions of heat sources and sinks. [22][23][24]36] Beyond the standard approach of constant compressor efficiencies, sometimes simple empirical compressor models were used.…”

Energy and parametric analysis of Organic Rankine Cycle combined with a vapor compression refrigeration cycle (ORC-VCR) system using natural refrigerants

“…al. [15] investigated the energetic and exergetic performance, as well as the environmental impact, of three vapor compression system configurations using R290, R600a, and R1270 as R134a replacements. A single-stage cycle, a cycle with an internal heat exchanger, and a two-stage cycle with vapor injection are three configurations used for investigation.…”

A Theoretical Comparative Study of Vapor-Compression Refrigeration Cycle using Al2O3 Nanoparticle with Low-GWP Refrigerants

“…The vapor-compression refrigeration cycle (VCRC) is widely used in domestic and industrial sectors due to its higher Coefficient of Performance (COP) [ 1 , 2 , 3 ]. VCRCs have a share of about 30% of the total world energy consumption, and this ratio may increase due to refrigerant leakage [ 4 , 5 ]. The performance of the refrigeration system can be improved either by increasing the rate of heat absorption in the evaporator or by reducing the compressor power.…”