Erna Tan

Performance of greenery systems in Zero Energy Building of Singapore

Aiming to be “City in a Garden”, greenery systems are widely developed to be integrated into buildings in Singapore. Zero Energy Building of Singapore as a test bed for several green building technologies also tested the greenery systems. Vertical greenery systems and extensive rooftop greenery systems were installed and the thermal performance was being monitored. The paper discussed on the performance of the greenery systems in reducing heat gain into the building and cooling down the ambient air temperature. The study was conducted by field measurement of the surface temperature and the ambient air temperature.

Influence of Water bodies on Outdoor Air Temperature in Hot and Humid Climate

Water features, within an urban area have a positive effect on the microclimate of the surrounding areas when natural cooling from evaporative process is needed in the hot sunny day. The increased availability of water usually enhances evaporation, and the associated uptake of latent heat provides and additional daytime cooling effect. The water bodies of the river operate as the cooling source on the microclimate of the surrounding area. Air temperature near or over bodies of water is much different from that over land due to differences in the way water heat and cool. Water bodies are noted to be about the best absorbers of radiation, but on the other hand, they exhibit very little thermal response. Many other researches argued that evaporative cooling from water bodies or water features is yet one of the most efficient ways of passive cooling for building and urban spaces. However, evaporative cooling may not work optimally in a hot humid tropical country due to its relatively high humidity. This paper studies the evaporative cooling performance of a waterway of approximately 70m to its surrounding micro-climate. The waterway is situated in Kallang, Singapore. The air temperature and relative humidity are measured continuously for five months, May and September 2010, to find the clear extent of the cooling effect from the waterway horizontally. There is a total of 10 measurement points in each location, where five points of measurement are located along the waterway and another five points of measurement are located moving away from the waterway in order to observe the extent of its cooling effect.

STEVE Tool Plug-in for SketchUp: A User-Friendly Microclimatic Mapping Tool for Estate Development

Due to increasing urbanization and heat island issues, current cities need to sensibly plan their future developments to preserve the quality of their urban environment. An urban climatic map (UCmap) method can be utilized for this purpose to examine the effectiveness of various urban environmental solutions in improving environmental conditions, particularly in terms of outdoor temperature and human thermal comfort. The available climatic models for both temperature and thermal comfort mapping can be deemed complicated and less user friendly; particularly for practitioners such as urban planners. Hence, the Screening Tool for Estate Environment Evaluation (STEVE Tool) and Thermal Sensation Vote (TSV) models were developed with a motivation to link research findings with urban planners. This paper showcases the models which have been developed as a plug-in for Trimble SketchUp (formerly Google SketchUp and hereinafter simply SketchUp); serving as a straightforward analysis tool for urban planners during the design and feasibility study processes. This plug-in can generate various climatic maps and sectional temperature profiles. Furthermore, it is also equipped with a plants database from the National Parks Board (NParks) and thus is able to calculate the impact of landscaping on temperature and carbon sequestration accordingly. A case study has been provided, using a central business district (CBD) area in Singapore. In the end, the generated UCMaps are able to provide microclimate information for an existing masterplan or urban morphology layout, so that planners or architects can identify the hot spots or problematic areas and then solutions or mitigation strategies can be developed afterwards by analysing the UCMaps.

Mitigation Methods of Climate Change Impact on the Cooling Load of Public Residential Buildings in Singapore

AbstractBuildings have time-varying interactions with the local climate condition for the heating or cooling systems; changes of the surrounding climate condition affect building energy consumption. Based on the thermal envelope approach, which considers the heat gain by conduction and radiation through the wall and fenestration, the cooling load simulation study was conducted to see the impact of climate change on the cooling load of public residential buildings in Singapore and propose mitigation methods to bring the predicted increase of the cooling load in the future back to the current level. From the simulation results, climate change is predicted to increase the cooling load of current public residential models for 11.8–55.8% through three different time frames. Based on the parametric study of mitigation methods proposed, changing the material of the wall, material of the glass, and the surface properties show a smaller increase in the predicted cooling load compared with other methods because of ...

Performance of passive design features in Zero Energy Building of Singapore

Zero Energy Building (ZEB) of Building and Construction Authority (BCA) in Singapore is a retrofitted building with different green building design features and technologies. It is used as a test-bed for innovative building designs and energy efficient building solutions, particularly for existing buildings. The study focused on the performance of shading devices and lightshelves in providing daylighting and affecting the thermal comfort in naturally ventilated classrooms under afternoon sun. Field physical measurements were conducted to compare the space with and without the passive design elements. For the shading devices, the complete setting configuration showed higher mean radiant temperature reduction of around 1°C - 2°C. The illuminance level of the complete setting configuration showed around 100 lux more reduction than the 4panel configuration. For the lightshelves, the reflective surface improved about 100 lux at 1pm and did not improve much afterward. The mean radiant temperature showed a lag of half an hour. The zone with the reflective surface was heated up earlier and in overall, the temperature was increased of around 1°C deeper in the room.