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This study highlights the energy and environmental impacts of a multigeneration system for infectious medical waste -to-energy (IMWtE). Thermal performance and life cycle assessment (LCA) are investigated via the energy conservation, ReCiPe method, SimaPro database, and situation of environmental issues in Thailand and worldwide. A lifespan of 20 y is considered in this study. The energy results show that the multigeneration system can produce a net power of 15.80 kWe from an organic Rankine cycle (ORC), 4.62 kW of cooling power from an absorption chiller, and 13.21 kW of heating power from a drying room. An overall system efficiency of 13.40% is directly driven from an infectious medical waste (IMW) of 81.98 kg/s. According to the LCA results, the construction phase has the highest emissions (81%), followed by the operation phase (6%) and the landfill (1%). The recycling process reduces the environmental impact by 12%. The total lifetime midpoint impact is 3.88E-01 kg emission-eq/kWh. The endpoint includes 4.33E-07 DALY/kWh of human health, 1.50E-06 Species·y/kWh of ecosystem, and 3.81E-03 USD/kWh of resources. The LCA single score is approximately 6.08E+02 Pt/lifespan or 5.63E-04 Pt/kWh.

This work presents an infectious medical waste-to-energy (IMWtE) thermal and environmental analysis using combined heat and power (CHP) technology. Steam sterilization can be operated with an infectious medical waste (IMW) of 375 kg/h⋅unit, a maximum per day of 12,000 kg/day for double sterilization units, and a running time of 16 h/day. The CHP system uses a dried IMW of 797 kg/h, generating a power output of 128.98 kWe, providing a drying heat of 382.91 kW, and achieving an overall system efficiency of 8.45 %. Results are obtained for a life cycle assessment (LCA) of the IMWtE by CHP system technology. The endpoint effectiveness comprises considerations of human health: 2.83E+01 DALY, ecosystem quality is represented value of: 9.32E+00 Species⋅y, and natural resource value of: 1.08E+06 USD, all of these are fundamentally linked to the utilization of steel, copper, paint, and gypsum. The LCA impacts are primarily due to the operation phase (93 %), with the smaller contribution of the decommissioning phase (4 %), and the construction phase (3 %), respectively.

Groundwater temperature is one of the main factors that is considered when deciding on installation of a vapor compression refrigeration system with groundwater used for heat transfer. Groundwater temperature measurement is a necessity for the system installation. A total of 75 groundwater wells within the Chiang Mai Basin were selected for temperature monitoring stations. The temperature-depth profile of shallow groundwater showed that temperature had little change below 2 m depth from the water table. The temperature-depth profile of deep groundwater showed the separation of upper and lower temperature zones. Mostly, the temperature of the upper zone of deep groundwater has a positive slope. The temperature of the lower zone of deep groundwater is relatively constant. Both the shallow and deep groundwater temperatures are below the atmospheric temperature. The seasons, hydrogeologic units, and land use types have affected groundwater temperature of the Chiang Mai Basin only little.

This research presents a hybrid waste–solar power generation and waste disposal system in Luang Prabang, Lao. A waste management problem of 19,546.52 Ton in 2021 is the focus of waste-to-energy (WtE) technology. A 230-kg/h steam sterilization method is used to autoclave hazardous waste combined with a 40-kW drying room to produce type 3 refuse-derived fuel (RDF-3). The hybrid system generates 221.03 kWe of power at a system efficiency of 6.67%. A levelized electricity cost (LEC) of 0.29 USD/kWh and a carbon dioxide emission of 0.156 kg CO2/kWh are achieved to address economic and environmental impacts.

In this study, the thermal, energy, economic, and environmental perspectives of a smart Cannabis plantation are investigated. A commercial R-32 air conditioning at a cooling capacity of 12,300 BTU/h is implemented for the 5-lighting sets. One 300 We-violet-light-emitting diode (LED) and two 100 We-daylight-LEDs are designed for one lighting set at a photosynthetic photon flux density of 100 µmol/m2⋅s. A smart watering system is designed to automatically control a watering period of 62 h, an operating time of 40 min, and a watering rate of 41.5 L/time. The smart Cannabis plantation can produce a fresh inflorescence of 250 g and a dried inflorescence of 46.3 gdy, respectively. A power consumption of 126.9 kWh/plant is mainly driven the environmental impacts of a climate change of 6.22E+02 kg CO2 eq/kgdy. The economic result of a levelized cost is approximately 262.85 USD/kgdy.

This work investigates the thermal performance of a cascade-combined system from the 23.65-kWe organic Rankine cycle (ORC), 4.00-kW adsorption, 4.11-kW absorption chillers, and 15.99-kW dying room. The incinerator is used to generate a hot fluid temperature of 105.38 °C from an RDF-3 of 92.21 kg/h at a low heating value of 26.92 MJ/kg. Three phase powers of 11.98 kWe, a chilled water temperature of 10.48–11.86 °C, and dried golden-longan at a final moisture content of 39.88% wet basis are produced from the integrated system at energy and exergy efficiencies of 12.25% and 25.88%. The average energy cost is 0.136 USD/kWh.

This research studies the life cycle assessment (LCA) of a novel combined cooling, heating, and power (CCHP) generation system. The geothermal energy of the San Kamphaeng Hot Spring, Thailand was developed. The multistep utilization of a R-245fa organic Rankine cycle (ORC) of 10 kWe, a water-lithium bromide absorption chiller of 10 kW, and a drying room of 18.77 kW were implemented to investigate eighteen impact categories (ReCiPe 2016). The LCA results were determined as a single score of approximately 6.31E-02 points.

The worldwide emission regulations for compression ignition (CI) engines have become more stringent driven by global warming issues and public health concerns. A promising solution to decrease greenhouse gas and emissions from CI engines is gasohol considered as a fuel-replacing diesel. The objective of this study is to study effect of gasohol on fuel injection characteristics of a common rail injection system used in CI engines. Gasohol E85, containing 85% ethanol and 15% gasoline, is tested and conventional diesel is a reference fuel. An injection measurement device based on Zeuch method was used for investigating the injection characteristics including injected amount and discharge coeffi cient. Gasohol were injected with both single and double injection strategies at a constant injection pressure of 450 bar into a back-pressure of 40 bar. The fi ndings of this study clearly show that injection characteristics of gasohol were signifi cantly differed from those of diesel, due to physical properties changed. At the same injection conditions, injected fuel rate are different.

In this study, simulation and experiment studies of a 10 kW solar H2O–LiBr absorption heat transformer (AHT) integrating with a two-stage vapor compression heat pump (VCHP) were carried out. The whole system was named as compression/absorption heat transformer (CAHT). The VCHP was used to recover rejected heat at the AHT condenser which was transferred back to the AHT evaporator at a higher temperature. The AHT unit took solar heat from a set of flat-plate solar collectors in parallel connection. R-134a and R-123 were refrigerants in the VCHP cycle. From the simulation, the total cycle coefficient (COP) of the solar-CAHT was 0.71 compared with 0.49 of the normal solar-AHT. From the experiment, the total cycle COPs of the solar-CAHT and the solar-AHT were 0.62 and 0.39, respectively. The experimental results were lower than those of the simulated models due to the oversize of the experimental compressor. The annual expense of the solar-CAHT was found to be 5113 USD which was lower than 5418 USD of the solar-AHT. So it could be concluded that the modified unit was beneficial than the normal unit in terms of energy efficiency and economic expense.

In this study, a concept of using phase change material (PCM) for improving cooling efficiency of an air-conditioner had been presented under Thai climate. Paraffin waxes melting point at around 20 °C 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. Moreover, 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 the simulated data agreed quite well with the experimental result at the discrepant around 2–4%. Finally, the model was used to analyze the economic result which was found that the electrical consumption of the modified air-conditioner could be decreased 3.09 kW h/d. The electrical power consumption of the modified unit was 36.27 kW h/d at the operating time 15 h/d compared with 39.36 kW h/d of the normal unit at the operating time 12 h/d. The saving cost of the PCM bed could be 9.10% or 170.03 USD and the payback period was 4.15 y.

This study presents a new waste-to-energy-to-zero management under the energy, economic, and environmental implications. The survey data implies a total municipal solid waste (MSW) generation of 17.85 Ton/d. The proportions of combustible waste, noncombustible waste, and organic waste are 31.63%, 35.24%, and 33.13%, respectively. Combustion heat is utilized to fuel a combined cooling, heating, and power (CCHP) system. A power output is generated with a two-stage organic Rankine cycle (ORC) of 55.57 kWe, a cooling process in an absorption chiller of 91.06 kW, and a heating process in a drying room of 207.39 kW. A total energy output of 306.98 kW and an energy efficiency of 22.38% are simulated in the waste CCHP system. The solar photovoltaic (PV) rooftop system produced 2,755.62 kWh/d of power generation at a maximum efficiency of 16.28%. A waste-to-energy system has a net power output of 2,823.86 kWh/d at an overall efficiency of 18.34%. Concrete, copper, steel, and gypsum materials significantly influence all midpoint impact categories in the LCA. The main LCA is 6.01E-02 kg CO2 eq/kWh for climate change, 5.04E-02 kg 1,4-DB eq/kWh for human toxicity, and 1.74E-02 kg Fe eq/kWh for mineral resource depletion. A levelized energy cost (LEnC) of 0.15 USD/kWh, a net present value (NPV) of 1,634,658.51 USD, a profitability index (PI) of 1.72, an internal rate of return (IRR) of 7.97%, and a payback period (PB) of 9.63 y are achieved for economic impact. A waste-to-zero method presents a waste ash concrete block of 7.50 kg, with a size of 39 cm × 19 cm × 7 cm, developed under the Thai Industrial Standard (TIS) 58–2533.