Identifying suitable general circulation model for future building cooling energy analysis

These future building energy studies mainly stem from hourly based dynamic building simulation results with the future weather data. The reliability of the future building energy forecast heavily relies on the accuracy of these future weather data. The global circulation models (GCMs) provided by IPCC are the major sources for constructing future weather data. However, there are uncertainties existed among them even with the same climate change scenarios. There is a need to develop a method on how to select the suitable GCM for local application. This research firstly adopted principal component analysis (PCA) method in choosing the suitable GCM for application in Taiwan, and secondly the Taiwanese hourly future meteorological data sets were constructed based on the selected GCM by morphing method. Thirdly, the future cooling energy consumption of an actual office building in the near (2011-2040), the mid (2041-2070), and the far future (2071-2100), were analysed. The results show that NorESM1-M GCM has the lowest root mean square error (RMSE) as opposed to the other GCMs, and was identified as the suitable GCM for further future climate generation processing. The building simulation against the future weather datasets revealed that the average cooling energy use intensity (EUIc) in Taipei will be increased by 12%, 17%, and 34% in the 2020s, 2050s, and 2080s, respectively, as compared to the current climate

Analysis of Incorporating a Phase Change Material in a Roof for the Thermal Management of School Buildings in Hot-Humid Climates

Strategies to reduce energy consumption are presently experiencing vigorous development. Phase change materials (PCMs) are novel materials that can reduce indoor temperatures via the change in material phase. Regarding the situation in Taiwan, there is no practical utilization of PCMs in school buildings at present, especially in combination with rooftops. In this paper, we discuss the feasibility and utilization potential of installing PCMs in the rooftops of school buildings. School buildings located in northern and southern Taiwan (Taipei and Kaohsiung) were selected to analyze the energy-saving potential and optimization of indoor thermal comfort by installing PCMs with different properties in rooftops over two time periods, including the air conditioning (AC) and natural ventilation (NV) seasons. Based on the simulation results, the feasible patterns of PCM simultaneity are found to be appropriate for improved indoor comfort and energy saving during the different seasons. Specifically, the efficient phase change temperature (PCT) for different PCM thicknesses is clarified to be 29 °C. The economic thickness of PCM was clarified to be 20 mm for Taipei and Kaohsiung. Through the recommendations proposed in this study, it is expected that the PCMs may be efficiently implemented in school buildings to realize the goal of energy conservation and improve thermal comfort

Influence of Urban Microclimate on Air-Conditioning Energy Needs and Indoor Thermal Comfort in Houses

A long-term climate measurement was implemented in the third largest city of Taiwan, for the check of accuracy of morphing approach on generating the hourly data of urban local climate. Based on observed and morphed meteorological data, building energy simulation software EnergyPlus was used to simulate the cooling energy consumption of an air-conditioned typical flat and the thermal comfort level of a naturally ventilated typical flat. The simulated results were used to quantitatively discuss the effect of urban microclimate on the energy consumption as well as thermal comfort of residential buildings. The findings of this study can serve as a reference for city planning and energy management divisions to study urban sustainability strategies in the future

Strengthening Taiwan’s Green Building Certification System from Aspects of Productivity and Energy Costs to Provide a Healthier Workplace

This study estimates the relationship between poor indoor environmental quality (IEQ) and the increasing labor costs in green buildings in Taiwan. Specifically, poor performance of IEQ including HVAC, lighting, and indoor air quality, influences the health and well-being of occupants and leads to worse productivity, ultimately causing increased personnel cost. In Taiwan’s green building certification (GBC) system, the energy-savings category is mandatory while the IEQ category is only optional. It means that certified building cases may not reach the expected level in IEQ. Thus, this study reviews the thermal environment, indoor air quality (IAQ), and illumination performances of IEQ-certified and non-IEQ-certified buildings in 20 green buildings. Building energy and IEQ simulations were conducted to analyze the relationships between indoor comfort, energy cost, and personnel cost in green buildings. The results show that IEQ-certified green buildings averagely perform better than non-IEQ-certified ones in the aspects of IEQ and building costs. Besides, 3 of 13 non-IEQ-certified green buildings undertake extremely high additional expenditure for the poor IEQ. The results correspond to some previous findings that green-certified buildings do not necessarily guarantee good building performance. This study further inspects the pros and cons of Taiwan’s GBC system and proposes recommendations against its insufficient IEQ evaluation category. As the trade-off of energy-saving benefits with health and well-being in green buildings has always been a concern, this study aims to stimulate more quantitative research and promote a more comprehensive green building certification system in Taiwan

Strengthening Taiwan’s Green Building Certification System from Aspects of Productivity and Energy Costs to Provide a Healthier Workplace

This study estimates the relationship between poor indoor environmental quality (IEQ) and the increasing labor costs in green buildings in Taiwan. Specifically, poor performance of IEQ including HVAC, lighting, and indoor air quality, influences the health and well-being of occupants and leads to worse productivity, ultimately causing increased personnel cost. In Taiwan’s green building certification (GBC) system, the energy-savings category is mandatory while the IEQ category is only optional. It means that certified building cases may not reach the expected level in IEQ. Thus, this study reviews the thermal environment, indoor air quality (IAQ), and illumination performances of IEQ-certified and non-IEQ-certified buildings in 20 green buildings. Building energy and IEQ simulations were conducted to analyze the relationships between indoor comfort, energy cost, and personnel cost in green buildings. The results show that IEQ-certified green buildings averagely perform better than non-IEQ-certified ones in the aspects of IEQ and building costs. Besides, 3 of 13 non-IEQ-certified green buildings undertake extremely high additional expenditure for the poor IEQ. The results correspond to some previous findings that green-certified buildings do not necessarily guarantee good building performance. This study further inspects the pros and cons of Taiwan’s GBC system and proposes recommendations against its insufficient IEQ evaluation category. As the trade-off of energy-saving benefits with health and well-being in green buildings has always been a concern, this study aims to stimulate more quantitative research and promote a more comprehensive green building certification system in Taiwan

Establish high-resolution hourly weather data for simulating building energy consumption in different regions

Due to the various local weather conditions in different regions of the city, the demand for air conditioning (AC) of housing is different, too. It happened occasionally to underestimate the energy consumption of AC in urban areas, because of using suburban/rural weather station data for building energy simulation. This study set up 34 automatic weather stations in the urban area of Tainan City, Taiwan for a year-round collection of local temperature and relative humidity data. Those weather measurement, the GIS information of a buffer zone and multiple regression analysis were used to establish the relationship between the weather factors, needed for the morphing approach, and the parameters of landscape use and cover. The buffer zone is an area of 1000×1000 m2 around the measured point, and is divided to two layers with upwind and downwind parts. Local hourly weather-year files for a whole of the city with a resolution of 200×200 m2 were generated by the morphing approach. With the different local hourly weather-year files, the AC-required hours and energy consumption from May to October for a typical residential with hybrid ventilation mode was obtained by using the EnergyPlus. And the cumulative UHI of each grid between May and October is calculated by taking the average of the five lowest temperatures as the reference value. The result shows that the number of AC hours of residential will increase by 10%, and the energy consumption increase from 1000 kWh to 2500 kWh, when long-term UHI intensity increases from 2000 °C-hour to 9000 °C-hour

Quantification of the effect of thermal indices and sky view factor on park attendance

Outdoor shading affects the thermal environment and human thermal comfort, thereby influencing the usage of space. The objective of this study is to establish a relationship between the thermal environment and number of people visiting an outdoor space, and to explore the utilization of outdoor space during different seasons with various shading levels. This study includes onsite investigations of the microclimate parameters of the thermal environment and attendance at a park in central Taiwan. The results in cool seasons showed a positive correlation among the air temperature, mean radiant temperature (Tmrt), and physiologically equivalent temperature (PET) of shaded areas and the number of visitors. In hot seasons, the Tmrt and PET, which also reflect solar radiation conditions, are negatively correlated with the number of visitors. In other words, the higher Tmrt/PET values indicate that fewer people visit the park during the summer. Meanwhile, a significant correlation exists between park utilization and solar radiation conditions. This study proposes the use of area-averaged sky view factor (SVFa), instead of the traditional single-point sky view factor from fisheye photographs (SVFsp), as the indicator for measuring the shading level at various areas in parks. Analytical results indicate that the lower the SVFa, the higher the park utilization. This study highlights the importance of shade design in parks located in tropical or subtropical climates. The results can serve as a reference for park design in the future

Microstructure of chromium spinel and pyrite as indicators of thermomechanical history of chromitite from Kenting melange, Taiwan

Transmission electron microscopy was used to characterize the microstructure of chromium spinel and pyrite in the serpentinized chromitite occurrence of the Kenting melange at Hengchun, southern Taiwan. The deformation episodes of the Hengchun chromitite were then inferred from the defect microstructures on the basis of the known creep behaviour of analogue spinel materials and pyrite. Dislocations arranged as dipoles, tangles and subgrain boundaries were found in chromium spinel indicating that the chromium spinel was probably plastically deformed and polygonized later in the upper mantle. The dislocations arranged as dipoles, loops, tangles and subgrain boundaries in pyrite correspond probably to later episodes of the ocean floor metamorphism during which dynamic recrystallization of pyrite occurred, together with brittle deformation of chromium spinel. The breccias of chromium spinel and pyrite are in part due to brittle deformation during emplacement of the ophiolite at a convergent plate boundary.Les chromitites serpentinisées du mélange de Kenting contiennent des spinelles chromifères et de la pyrite. L'étude au microscope électronique en transmission de ces minéraux a permis de caractériser leurs microstructures. Les épisodes de déformation ainsi mis en évidence dans la chromite sont comparés avec les données connues sur le comportement thermomécanique des spinelles et de la pyrite. On montre de cette manière l'origine ophiolitique des chromites. L'analyse des dislocations dans les spinelles chromifères montre qu'elles ont été déformées plastiquement et polygonisées dans le manteau supérieur. Les dislocations en dipôle, en boucles, en échevaux et en "sous-joints" dans les pyrites correspondent aux derniers épisodes de métamorphisme du plancher océanique. Pendant cet épisode a eu lieu une recristallisation dynamique des pyrites et une déformation cassante des spinelles. Les brèches de spinelles chromifères et des pyrites sont en partie le résultat d'un stade de déformation cassante pendant la mise en place des chromitites ophiolitiques à la frontière convergente des plaques.Hwang Shyh-Lung, Shen Pouyan, Chu Hao-Tsu, Jeng Ruey-Chang. Microstructure of chromium spinel and pyrite as indicators of thermomechanical history of chromitite from Kenting melange, Taiwan. In: Bulletin de Minéralogie, volume 111, 5, 1988. pp. 457-469