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To reduce energy consumption, the time needed of drying, and the loss of ß-carotene content, and ascorbic acid content, response surface methodology (RSM) was employed for optimization.

To reduce energy consumption, the time needed of drying, and the loss of ß-carotene content, and ascorbic acid content, response surface methodology (RSM) was employed for optimization.

The results show that the optimum solar-assisted heat pump drying (SAHPD) conditions for drying pumpkin slice were: drying temperature of 67.40 °C, loading density of 1.05 kg/m³, and material thickness of 4 mm. Under these conditions, slice of pumpkin were dried in 440.637 min, where the unit energy consumption, ascorbic acid content, and ß-carotene content were 16.737 kJ/g, 25.682 mg/ (100–g dried sample), and 10.202 mg/g, respectively. The structure of the samples dried using the optimized SAHPD method exhibited a more complete cell morphology than those dried using heat pump drying when examined using scanning electronic microscopy.

This suggests that the optimized SAHPD conditions used in this study are important for production and processing.

Water heating is one of the major energy‐consuming operations in the lodging sector. The purpose of the current study is to estimate the energy consumed and emission associated with hot water usage, to predict the energy cost required under different hot water systems in hotels; and to create a model for the decision‐making criteria in selecting hot water systems.

A total of 24 hotels, which use heat pumps as their main water heating systems, were investigated. A tailor‐made model for estimating the energy requirement of the water heating system was employed. Comparative studies on the energy consumption and energy costs of various types of water heating systems, including heat pumps, diesel boilers, gas boilers, and electric boilers, were conducted. Moreover, an analytic hierarchy process was used to analyze hoteliers' and lenders' selection criteria for water heating facilities.

The energy output for water heating by heat pumps was estimated at 15 GW in the lodging sector. The use of heat pumps can achieve substantial energy savings and reduction of air pollutants when compared with the energy requirements under conventional boilers. The latter accounts for 13 percent of the hoteliers' total decision weight on choosing water‐heating systems. Whereas the air pollutants generated by gas‐fired boilers are remarkably lower than those emitted in the power plants due to the use of heat pumps. Both bankers and hoteliers consider seriously the energy saving potential of hot water supply by trucks.

Due to the small number of decision‐makers in hotels participating in the analytic hierarchy process, the result can only provide an indication of the overall picture of the selection criteria adopted by hoteliers.

The analysis provides hotel owners and managers with an objective and scientific investigation of the emission prediction and energy cost estimation based on the use of different hot water systems. Hotel operators and owners can use the analytical results as reference for making green purchasing decisions.

The current study, which is based on the operational experiences of existing hotels, is a collaborative work between hospitality industry practitioners and educators. It is also the first of its kind to indicate the emission impact of various types of hotel water heating systems and the perspectives of hoteliers and bankers on these systems.

In this study, a solar water heating system along with a seasonal thermal energy storage and a heat pump is designed for a villa with an area of 192 m² in Tehran, the capital of Iran.

According to the material and the area of the residential space, the required heating of the building was calculated manually and then the thermodynamic analysis of the system and simulation was done in MATLAB software. Finally, regarding the waste of system, an efficient solar heating system, providing all the required energy to heat the building, was obtained.

The surface area of the solar collector is equal to 46 m², the capacity of the tank is about 2,850 m³, insulation thickness stands at 55 cm and the coefficient of performance in required heat pump is accounted to about 9.02. Also, according to the assessments, the maximum level of received energy by the collector in this system occurs at a maximum temperature of 68ºC.

To the best of the authors’ knowledge, in the present work, for the first time, using mathematical modeling and analyzing of the first and second laws of thermodynamics, as well as using of computational code in MATLAB software environment, the solar-assisted ground source heat pump system is simulated in a residential unit located in Tehran.

This paper aims to present a numerical study on the natural convection, which operates either as an evaporator or condenser unit of the heat pump system to pre-cool and pre-heat the ambient fresh air.

This study focuses on natural air cooling or heating within the air channel considering the double skin configuration. Particular focus is given to the analysis of airflow and the heat transfer processes in an air channel to cool or heat the ambient fresh air. In this study, the physical model consists of one wall, either heated uniformly or cooled uniformly, whereas the other wall is adiabatic.

The results show that the variation of both velocity and temperature is observed as the flow transition occurs at the evaporator or condenser wall. In either case, the temperature rises in the range of 6.3–8.4°C with an increase in mass flow rate from 0.07–0.08 kg/s in the photovoltaic thermal condenser part, while in the photovoltaic thermal evaporator part, the change in mass flow rate from 0.048–0.061 kg/s causes a decrease in temperature from 7.1–4.5°C.

The solar-assisted photovoltaic thermal heat pump system, in building façade having an air layer application, is feasible for pre-heating and pre-cooling the ambient fresh air and also reduces the energy needed to treat the fresh air.

The influence of condensing and evaporating temperature under natural convection mode in double skin conformation is considered for pre-heating and pre-cooling of ambient fresh air.

The residential buildings sector has a high priority in the climate change adaptation process due to significant CO₂ emissions, high energy consumption and negative environmental impacts. The article investigates how, conversely speaking, the residential buildings will be affected by climate change, and how to improve existing structures and support long-term decisions.

The climate dataset was created using the scenarios determined by the Intergovernmental Panel on Climate Change (IPCC), and this was used in the study. Different building envelope and Heating, Ventilating and Air Conditioning (HVAC) systems scenarios have been developed and simulated. Then, the best scenario was determined with comparative results, and recommendations were developed.

The findings reveal that future temperature-increase will significantly impact buildings' cooling and heating energy use. As the outdoor air temperatures increase due to climate change, the heating loads of the buildings decrease, and the cooling loads increase significantly. While the heating energy consumption of the house was calculated at 170.85 kWh/m² in 2020, this value shall decrease significantly to 115.01 kWh/m² in 2080. On the other hand, the cooling energy doubled between 2020 and 2080 and reached 106.95 kWh/m² from 53.14 kWh/m² measured in 2020.

Single-family houses constitute a significant proportion of the building stock. An in-depth analysis of such a building type is necessary to cope with the devastating consequences of climate change. The study developed and scrutinised energy performance improvement scenarios to define the climate change adaptation process' impact and proper procedure. The study is trying to create a strategy to increase the climate resistance capabilities of buildings and fill the gaps in this regard.

The purpose of this paper is to present the advantages of a solar store system with transpired solar air collector (TSC) in North Wales, UK. The collectors are designed as a proposal to meet the target of the solar air storage and heating project to improve the efficiency of solar collectors in the UK.

IES software simulation is used to examine the potential of a solar store system in Deeside Leisure Centre compared to the traditional constant air volume (CAV) system and CAV system with heat pump. The design parameters and configurations are determined on the basis of the monitoring results gained from recent experiments.

The result demonstrates good agreement between simulations and monitoring results and the solar store system demonstrates considerably lower energy consumption compared to the traditional CAV system with and without heat pump.

The usage of TSC is proven to be useful in improving COP of the heat pumps and reducing overall energy consumption in a leisure center. The framework proposed in this study could also be applied to different building types in order to highlight their advantages.

The purpose of this paper is to evaluate the energy, economic and environmental performance of commercial water heating systems in Hong Kong special administrative region (SAR), China.

The research team contacted 50 facilities managers in Hong Kong, and 16 of them agreed to participate in this territorial-wide survey. The overall efficiency of different water heating systems was determined through measurements of inlet water temperatures, outlet steam/water properties, the amount of steam/water produced and the amount of energy consumed. The cost effectiveness and the amount of greenhouse gases produced per megajoule (MJ) output were also determined.

Results show that electric water heating systems had the highest mean overall efficiency, followed by gas- and oil-fired systems. However, the difference between the mean overall efficiency of the three types of water heating systems was not statistically significant, as the systems had been inspected and maintained regularly. Oil-fired systems were found to be the most cost-effective when taking fuel prices into consideration. Environmental analysis showed that gas-fired systems produced the least amount of greenhouse gases per MJ output.

Water heating is one of the major uses of energy in buildings. Hence, the efficiency of a water heating system can have a significant effect on the overall performance of a building. This paper not only provides insight on the energy performance but it also evaluates the economic and environmental performance of water heating systems.

During the past several years, research and studies in the field of solar energy have been continuously increased. One of the substantial applications of solar energy is related to industrial utilization for the drying process by efficient heat transfer methods. This study aims to upgrade the overall performance of an indirect solar dryer using a solar absorber extension tube (SET) equipped with ball-type turbulators.

In this work, three various SETs including hollow (SET Type 1), 6-balls (SET Type 2) and 10-balls (SET Type 3), have been simulated using Fluent software to evaluate heat transfer characteristics and flow structure along the air passage. Then, the modified solar drying system has been manufactured and tested at different configurations.

The findings indicated that adding a SET improved the performance notably. According to the results, using turbulators in the tube has a positive effect on heat transfer. The highest overall thermal efficiency was found in the range of 51.47%–64.71% for the system with SET Type 3. The maximum efficiency increment of the system was found as 19% with the use of SET. Also, the average specific moisture extraction rate, which is a significant factor to survey the effectiveness of the dehumidification system was found between 0.20 and 0.38 kg kWh⁻¹.

In the present study, a novel SET has been developed to upgrade the performance of the solar dehumidifier. This new approach makes it possible to improve both thermal and drying performances.

This paper investigates the energy performance of aquatic centres in Victoria.

Physical and occupancy characteristics and energy consumption from various centres were analysed to understand the interrelationship between numerous factors that contribute to the energy consumption of these facilities.

The energy usage intensity of the facilities ranged from 632 to 2,247 kWh/m2 or 8 to 17 kWh/visit. Primary and secondary indicators were examined to find the key performance indicators.

This study sheds some light into the overall energy performance of aquatic centres in the temperate climate of Australia. More samples need to be collected to perform rigorous statistical analysis leading to a reliable benchmark model. System-wise investigation of energy consumption is required to determine where the energy is being used and the saving potentials of each system.

This study has arisen from the need of managers of large aquatic and recreation facilities to benchmark the energy consumption of their own facilities. This study will fill the gap that currently exists in the area of energy rating systems for aquatic centres.

The results of this study showed that aquatic centres consume around seven times more energy than a commercial office building. Thus, if the energy consumption of aquatic centres could be reduced by as little as only 10 per cent, at least 3.5 million tonnes of carbon dioxide emission can be reduced.

Environmental design standards for aquatic centres have generally been overlooked due to the complex nature of these buildings. As a result, this sector suffers from a general lack of both qualitative and quantitative information and benchmarking.

This study has covered many types of solar-powered air-conditioning systems that may be used as an alternative to traditional electrically powered air-conditioning systems in order to reduce energy usage. Solar adsorption air cooling is a great alternative to traditional vapor compression air-conditioning. Solar adsorption has several advantages over traditional vapor-compression systems, including being a green cooling technology which uses solar energy to drive the cycle, using pure water as an eco-friendly HFC-free refrigerant, and being mechanically simple with only the magnetic valves as moving parts. Several advancements and breakthroughs have been developed in the area of solar adsorption air-conditioners during the previous decade. However, further study is required before this technology can be put into practise. As a result, this book chapter highlights current research that adds to the understanding of solar adsorption air-conditioning technologies, with a focus on practical research. These systems have the potential to become the next iteration of air-conditioning systems, with the benefit of lowering energy usage while using plentiful solar energy supplies to supply the cooling demand.