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A combined cooling heating and power (CCHP) generation system in the San Kamphaeng hot spring, Thailand, is investigated by using a new parameter of levelized energy and exergy costings per life cycle assessment (LCA). The microscale CCHP system, which comprises a 10 kW organic Rankine cycle, a 15 kW absorption unit and a 20 kW centralized drying room, were tested and analyzed. The net output energy and exergy of the CCHP system were found to have 32.62 kWh and 6.98 kWh at average efficiencies of 11.6% and 11.2%, respectively. In the environmental results, the 4 main impacts were essentially driven from the climate change of 3.90 kg CO 2 eq/kJ, human toxicity of 2.96 kg 1,4 DB eq/kJ, metal depletion of 1.20 kg Fe eq/kJ and fossil depletion of 6.47E-01 kg oil eq/kJ. The LCA single score could be integrated as 0.026 Pt. In the economic impact, the levelized energy and exergy costings were 0.069 USD/kWh and 0.323 USD/kWh, respectively. Finally, in the new 3E and 4E models (3,4E-Chaiyat models), the levelized energy and exergy costings per life cycle assessment were found to be approximately 0.002 USD⋅Pt/kWh 2 and 0.008 USD⋅Pt/kWh 2 , respectively.

This paper presents enhancement efficiency of an organic Rankine cycle (ORC) by using an absorption system, which the 3 ORC-absorption models are considerably investigated. R-245fa is used to generate power of the ORC system. The 2 absorption types of an ammonia-water (NH3-H2O) solution and a water-lithium bromide (H2O-LiBr) solution are chosen as the absorption working fluids. The optimal systematical model is evaluated by using the energy efficiency, exergy efficiency, levelized electricity cost (LEC) and exergy cost (EC) indicators. From the simulation results, the conventional ORC unit showed the average energy and exergy efficiencies as approximately 6.98% and 11.51%, respectively. The suitable absorption type was the H2O-LiBr absorption unit at the higher energy and exergy coefficient of performances compared with that of the NH3-H2O absorption unit at approximately 37.23% and 22.69%, respectively. The model 1 (absorption unit replaced the ORC condenser) could simultaneously generate power and cooling energies at the average energy and exergy efficiencies of 20.61% and 21.54%, respectively, which was similarly with the model 2 (absorption unit combined with the ORC condenser to extract heat) at approximately 15.89% and 17.15%. The model 3 (absorption unit was used to produce cooled water for reducing heat at the ORC condenser) showed the highest energy and exergy efficiencies for only generating power as 7.21% and 12.16%. The suitable integrated model was the ORC-absorption model 1 because of the highest exergy efficiency, which was particularly supported by the lowest economics results of the LEC and EC values of 0.074 USD/kWh and 0.080 USD/kWh, respectively.

This research presents a very small incinerator combined with heating production (VICH). The objective of this study, a novel VICH system is designed, simulated, tested, and analyzed in terms of the computational fluid dynamics (CFD), energy, economic, environmental, and exergy (4E-CFD) analysis methods. The CFD assessment using three hot fluids—hot water, steam, and hot oil—the results implied that hot water was the best working fluid at an increased temperature of 116.57 °C for integration with an organic Rankine cycle (ORC). Moreover, the testing results implied that a refuse-derived fuel (RDF) at a low heating value of 16.62 MJ/kg could increase the hot water temperature to 111.18 °C, which was close to the CFD simulation result. The energy and exergy efficiencies were approximately 23.35% and 20.93%, respectively. A life cycle assessment (LCA) at a functional unit of 1 kgRDF-1 and a lifespan of 20 y found a climate change of 3.30E-03 kg CO2 eq, an ozone depletion of 1.52E-10 kg CFC-11 eq, a particulate matter formation of 8.36E-06 kg PM10 eq, a terrestrial acidification of 1.30E-05 kg SO2 eq, a freshwater eutrophication of 1.83E-06 kg P eq, a human toxicity of 1.81E-03 kg 1,4 DB eq, a terrestrial ecotoxicity of 2.25E-07 kg 1,4 DB eq, a freshwater ecotoxicity of 1.04E-04 kg 1,4 DB eq, a fossil depletion of 8.02E-04 kg oil eq, and a metal depletion of 6.69E-04 kg Fe eq. The LCA impacts were driven from 36.07% construction, 63.41% operations, 0.52% landfill decommissioning and 3.99% recycling. In the economic results, the levelized cost of the waste disposal combined heating process was approximately 0.006 USD/kgRDF.

The potential of using a new type of water hyacinth and municipal solid waste at the ratio of 50:50 %wt as a heat source for a 20 kW e organic Rankine cycle has been determined in terms of energy, economic and environment aspects (3E model). From the testing results, it was found that the thermal performance of the ORC efficiency shows a linear correlation with the temperature different of heat source and heat sink at amplified by 8–9%. Levelized electricity costing from a water hyacinth-MSW-ORC (WMORC) system was determined to be 0.086 USD/kWh. The environmental impacts, 0.172 kg CO 2 -eq of greenhouse gas emission was estimated from the utilization of 1 kg of the new fuel. The LCA of the WMORC system was 0.6078 kg CO 2 -eq for the electrical energy generation of 1 kWh. In the 3E model assessment, a new parameter of levelized electricity costing per carbon dioxide intensity was defined and was found to be 0.052 USD·kg CO 2 -eq/kWh 2 , which was 20% lower compared to 0.065 USD·kg CO 2 -eq/kWh 2 from the standard power plant in Thailand. Thus, this technique is an alternative sustainable solution to tackle the energy crisis, to limit waste as well as to reduce CO 2 emission in Thailand.

This paper focuses a method to enhance an organic Rankine cycle (ORC) efficiency by using the sorption systems (absorption and adsorption) for reducing the ORC condenser temperature. Energy efficiency, exergy efficiency and levelized electricity cost (LEC) are used to evaluate the optimal combined unit. Testing data from a 25 kWe R-245fa ORC prototype, a 1 TR water-LiBr absorption chiller and a 1 TR water-silica gel adsorption refrigeration are tested and analyzed performance curve of each technology to predict thermal performance of the ORC-sorption units at various operating conditions. Projection of the integrating unit of the ORC and sorption systems represent the better energy and exergy efficiencies, when the ORC condenser temperature is decreased. The ORC-absorption efficiencies in terms of energy and exergy increase 7.22%, while the ORC-adsorption system improve 12.46% compared with the normal ORC efficiencies. In economic impact, the LEC of the normal ORC unit is 0.1145 USD/kW h, which is higher than the ORC-absorption unit and the ORC-adsorption unit of 0.1088 USD/kW h and 0.1043 USD/kW h, respectively, at chilled water temperature output the absorption system at 7 °C. Thus, it could be concluded that the ORC-adsorption system is the optimal technique to enhance the ORC electricity generation process in terms of energy efficiency, exergy efficiency and electricity cost.

This work presents the analysis of energy, economic, environmental (3E), and exergy (4E) impacts for verifying a single implication value of renewable energy technology. An infectious medical waste incinerator combined with an organic Rankine cycle with R-245fa as working fluid is investigated the overall impacts. The experimental energy result are used to analyze an exergy efficiency of the quality level, a life cycle assessment (LCA) under the environmental effect, a levelized cost of the economic perspective, and a 4E decision score. The study results implied that the organic Rankine cycle-incinerator system could manage a refuse-derived fuel type 3 (RDF-3) of 184.42 kg/h from infectious medical waste to produce 23.65 kWe of power at an energy efficiency 0.91%, with at the same time, an exergy efficiency was approximately 0.89%. The LCA was characterized with the use of steel at a single score of approximately 0.00035Pt. The economic value was implied from a levelized energy cost of 0.153 USD/kWh under the 3E model, which was lower than that of a Feed-in Tariff (FiT) model for the solid-waste power plant in Thailand of 0.209 USD/kWh. A levelized exergy costing per life cycle assessment of 0.0000986 USD Pt/kWh2 was investigated under the 4E model.

A new definition of the energy, exergy, economic and environmental model (3,4E-Chaiyat models) was used to evaluate cascade air-cooled multigeneration from a single-stage organic Rankine cycle of 10 kWe, a single-stage absorption chiller of 15 kW, and a drying room of 20 kW, respectively. From the study results, a first-law efficiency of 17.23% was found to be higher than a second-law efficiency of 15.13%. According to a life cycle assessment (LCA), a single score of the energy model of approximately 0.0250Pt was lower than that of the exergy model of approximately 0.1223Pt. In the 3E model, a levelized energy cost per life cycle assessment (LEnCA) was approximately 0.0017 USD⋅Pt/kWh2 for an investment cost of 159,729 USD. At the same time, in the 4E model, a levelized exergy cost per life cycle assessment (LExCA) was approximately 0.0414 USD⋅Pt/kWh2, which was lower than that of the water-cooled multigeneration system (approximately 0.0442 USD⋅Pt/kWh2). Thus, the suitable cooling type for the cascade geothermal-multigeneration system used in San Kamphaeng, Thailand, is the air-cooled type.

The critical issue of waste management in Thailand has been rapidly increasing in almost all of the cities due to the economic growth and rising population that could double the amount of solid waste in landfill area. The alternative ways of waste treatment that have more efficiency and effectiveness in terms of energy, ecology, and resources become the key issue for each municipality to replace the old fashioned technology and be able to enhance the ability of solid waste problem management. Waste to energy is one of the favorable approaches to diminish the amount of waste to landfill and utilize waste for electricity. The aim of this study is to identify and quantify the life cycle impacts of the municipal solid waste (MSW) of Mae Hong Son municipality (MHSM), and the case study is the selected waste treatment technology of the Refuse-Derived Fuel (RDF) hybrid with 20 kW of Organic Rankine Cycle (ORC). The functional unit is defined as 1 t of MSW. The energy, environment, and resource impacts were evaluated by using Life Cycle Assessment (LCA); ReCipe and Net Energy Consumption were referred to calculate the environmental impacts and the benefits of energy recovery of WtE technology. Exergetic LCA was used to analyze the resource consumption, especially land use change. The results indicated that the environmental impacts were comparatively high at the operation stage of RDF combustion. On the other hand, the production stage of RDF illustrated the highest energy consumption. The ORC power generation mainly consumed resources from material and energy used. The ORC system demonstrated better results in terms of energy and resource consumption when applied to waste management, especially the land required for landfill. Substitution of electricity production from ORC system was the contributor to the reduction of both energy and resource consumption. Installation of spray dry and fabric filter unit to RDF burner can reduce heavy metals and some pollutants leading to the reduction of most of the impacts such as climate change, human toxicity, and fossil depletion which are much lower than the conventional landfill. LCA results revealed that the environmental impacts and energy consumption can be reduced by applying the RDF and ORC systems. The exergetic LCA is one of the appropriate tools used to evaluate the resource consumption of MSW. It is obviously proven that landfill contributed to higher impacts than WtE for waste management.

This work presents a technique to improve the thermal performance of an R-32 air conditioner by using ultrasonic waves. Two 1-TR air conditioners — one with and one without 40[Formula: see text]kHz/50[Formula: see text]W ultrasonic generators — were tested under controlled conditions in a 3.6[Formula: see text]m [Formula: see text][Formula: see text]m [Formula: see text][Formula: see text]m room. The air temperature and humidity conditions entering the condenser and evaporator coils were controlled under 12 conditions to mimic the climate of Thailand. The testing results indicated that the average energy efficiency ratio (EER) of the modified ultrasonic R-32 air conditioner unit was 3.685[Formula: see text]kWth/kWe and the normal R-32 unit without the ultrasonic generators was 3.375[Formula: see text]kWth/kWe. The testing conditions also indicated that the cooling efficiency of the modified system could be increased by approximately 7.69%. Moreover, the convective heat transfer coefficient of the modified ultrasonic R-32 unit was approximately 17.36% higher than that of the normal R-32 unit without the ultrasonic generators because the ultrasonic waves could increase the turbulence in the refrigerant flow and decrease the condensed water at the fan coil unit. In terms of economic results, the payback period of the modified unit based on the climate of Thailand ranged from 0.8–1.2 y, leading to a savings in power consumption of approximately 400–620[Formula: see text]kWh/y.

This research aims to study the environmental impact of a very small organic Rankine cycle (VSORC) combined with a municipal solid waste incinerator (MSWI). A life cycle assessment (LCA) of eighteen midpoint and three endpoint levels under the ReCiPe method was performed by using the SimaPro database. A functional unit of 1 kWh and a life span of 20 years were considered in the LCA study. From the study results, it can be found that the VSORC-MSWI unit can process cleaned infectious medical waste in the form of refuse-derived fuel type 3 (RDF-3) at a mass flow rate of 184.42 kg/h to produce a power of 23.65 kWe for an overall system efficiency of 0.91%. In the LCA results, all of the midpoint impact categories are considerably driven by the use of steel, while the endpoint values include a human health metric of 2.20E−07 DALY, an ecosystem quality of 2.03E−10 species⋅y, and a natural resource value of 1.18E−02 $. The main effect is driven by the construction, operation, and decommissioning phases, which occupy approximately 87.16%, 11.94%, and 0.90%, respectively. All of the environmental impacts can be summarized as a single score of 0.000348 Pt.

This study examines the power generation process of a very small power plant (VSPP)-municipal waste (MSW) from an organic Rankine cycle (ORC) with an incinerator. The refuse derived fuel type 3 (RDF-3) from a mixed fuel of the infectious medical and municipal wastes at a low heating value of 26.92 MJ/kg is the main heat source of the VSPP. RDF-3 is sterilized by using shredding and heating processes (hybrid steam sterilization). The mixed fuel at a disposal rate of approximately 92 kg/h is used to generate hot water and accumulated heat in a high-pressure tank of 1500 L. Hot water at the temperature and heating rate of approximately 105.38 °C and 240.32 kW, respectively, is generated from the incinerator at an energy efficiency of 31.66% and an exergy efficiency of 4.05%. In the heat-to-power process, the hot fluid is supplied through an R-245fa-ORC system to produce electricity at a gross power of 23.65 kWe. The ORC efficiency is investigated in terms of the energy and exergy of approximately 8.05% and 39.98%, respectively. The VSPP-MSW system reveals an energy efficiency of 0.91% and an exergy efficiency of 0.89%. In the economic results, the levelized exergy cost is 0.257 USD/kWh, which is slightly higher than that of the Feed-in Tariff (FiT) for integrated solid-waste management of 0.209 USD/kWh, but this method is economical for the disposal cost of the infectious medical waste in Thailand in the range of 0.494–0.659 USD/kg.

This paper focuses on the feasibilities of energy, economic and environment of a method to enhance an ORC (organic Rankine cycle) efficiency by CCHP (combined cooling heating and power) generation from an absorption system for reducing the ORC condenser temperature. A projection of a 25 kWe R245fa ORC integrated with a 20 kW LiBr-water absorption unit was considered. The experimental data of both units were generated as performance curves and used to find out the suitable operating conditions. It could be found that the ORC with the absorption system gave higher total efficiency compared with the normal ORC. The ORC efficiency could be increased around 7%, with 15 °C of cooled water temperature supplied from the absorption system. But, in term of the economic result, a LEC (levelized electricity cost) of the modified system was around 0.0891 USD/kWh, which was higher than that of the normal system at around 0.0669 USD/kWh. In term of the environmental impact, a released carbon dioxide intensity of the new unit was lower than the normal unit at around 0.203 and 0.216 kg CO2 eq/kWh, respectively.

In this study, a concept of using phase change material (PCM) for improving cooling efficiency of an air-conditioner had been presented under Thailand climate. Rubitherm20 (RT-20) was selected to evaluate the thermal performance by reducing the air temperature entering the evaporating coil. The model of PCM celluloid balls had been performed with the air-conditioner. For the experiment, 2 TR of R-134a air-conditioner was chosen to test a pack bed of PCM balls with thickness 40 cm. The pressure drops of the air flowing through the bed were considered with and without a set of by-pass tubes along the height of the storage bed. The mathematical model of the air-conditioner with the PCM storage was developed and verified with the testing results. From the study results, it could be seen that pressure drops of the bed with and without bypass tubes were nearly the same results. Thus, PCM ball pack bed using RT-20 without bypass tubes was used to improve the cooling efficiency of the air-conditioner. The experimental result of the modified unit was compared and verified with the mathematical model, which agreed quite well with the simulation result. Finally, the model was used to analyze the economic result, which found that the electrical consumption of the modified air-conditioner could be decreased around 3.09 kW h/d. The saving cost from the PCM bed could be 9.10% of 170.03 USD/y and the payback period was around 4.15 y.

This study presents a method for analysing air conditioner efficiency by using a thermal performance curve. Enhancement techniques consisting of the use of a phase change material (PCM), a vapor compression heat pump (VCHP), ultrasound, drop-in refrigerant, a commercial R-32 air conditioner using ultrasound and a double-storage tank are reported under the weather conditions in Thailand. For the PCM, Rubitherm20 (RT-20) in the forms of a paraffin ball and a plastic pack was selected to cool the return air of the evaporator, which directly caused decreases in power consumption of 7.85% and 5.78%, respectively. The R-123 VCHP was integrated with the air conditioner at the condenser to receive and boost rejected heat to the hot water temperature of 60–70∘C. Ultrasonic wave generators at 42[Formula: see text]kHz frequency were installed at the evaporator to improve heat transfer characteristics and reduce the electrical power usage of the air conditioner by 8%. The R-32 drop-in refrigerant technique was tested in an R-410a air conditioner model. The R-32 unit showed the advantages of a smaller environmental impact and a higher cooling energy efficiency ratio (EER) compared with that of the R-410a unit. Moreover, the commercial R-32 air conditioner and a 40 kHz ultrasonic generator were integrated. The combined unit revealed a higher EER of 7.69% compared with that of the conventional commercial R-32 unit. For a double-storage tank, it was shown that the maximum hot water temperature in the storage tank was approximately 49∘C. The highest effective method to enhance the cooling capacity of air-conditioner is the technique of R-32 air conditioner and ultrasonic wave for increasing the cooling efficiency of 8.54%.