Abdul Malek Abdul Rahman

A comparative study between unvented and vented attics powered by the hybrid turbine ventilator in Malaysian houses

Vented attic is a design technique that provides a better solution to reduce solar heat gains trapped in a roof attic. However, its application in the tropical climate is very rare if not, ignored, especially in Malaysian houses. This paper seeks to identify, and compare the performance of attic ventilation by a single hybrid turbine ventilator for a specific volume under both unvented and vented conditions. The study was done in an actual roof attic (10 m3) located in Universiti Sains Malaysia. The results indicate that the reduction of the attic air temperature was 6.4°C, while stabilising the level of relative humidity to about 40–50% which is higher than that for an unvented attic by 10%. Furthermore, the findings reveal that by incorporating a 50 W poly-crystalline solar panel with a turbine ventilator of Ø 45 cm, the peak value of the attic air velocity had exceeded 1.3 m/s when the solar radiation was observed to be around 800 W/m2.

Potential of fibre optic daylighting systems in tropical Malaysia

Fibre optic daylighting systems are a developing technology that offers solutions to daylighting designers. However, these systems are rarely used in the tropics because of the variable illumination provided by the sky, which changes with latitude, time of day, and seasons. This study examines the illumination levels obtained using a fibre optic daylighting system under various tropical climate conditions in Malaysia. A Parans SP3 fibre optic daylighting system with 10-m cable was used on a full-scale test bed model in Universiti Sains Malaysia as an empirical approach. The following results were obtained: (i) on sunny days with intermediate blue sky, the system worked at 79% and reached a maximum of 725 lx, an average of 457 lx, and a minimum of 98 lx; (ii) on moderately sunny days with intermediate mean sky, the system worked at 48.5% and reached a maximum 685 lx, an average of 439 lx, and a minimum of 80 lx; (iii) under overcast skies, the system worked at 37.5% and reached a maximum of 538 lx, an average of 305 lx, and a minimum of 41 lx. These findings provide benchmarking directions for the application of fibre optic daylighting systems in Malaysia.

Assessing the allowable daylight illuminance from skylights in single-storey buildings in Malaysia: a review

AbstractA skylight system casts uniform levels of natural light over an area with minimum obstruction either internally or externally. In tropical climates, especially near the equator, the levels of solar radiation and conditions of sky appearance represent the main limitation in this region. In Malaysia, the application of skylight systems to single-storey buildings is limited because of environmental constraints that discourage its adoption. Understanding the allowable level of daylight in an indoor environment is crucial. Many standards, guidelines, and studies have provided various levels, but the desired level is still under debate. Therefore, this research aims to review and evaluate the allowable useful illuminance of daylight in the indoor environment from a skylight in single-storey buildings (used for office work) under Malaysian sky conditions. This study provides a comprehensive review of previous research on understanding daylight illuminance and Malaysian sky conditions. Based on this compr...

A review study on the application of the fibre optic daylighting system in Malaysian buildings

As a developing country, Malaysia requires innovation to keep abreast of the rapid growth of technology to meet the highly demanding energy consumption. The application of daylighting systems especially by fibre optics is very limited, due to the absence of relevant knowledge and the lack of understanding of the system requirements and potentials, particularly the technology of illuminating enclosed spaces which are totally surrounded by internal walls (opaque). Thus, the aim of this literature review is to shed light on this new approach and to help the building technologists activate its application in building interiors. This paper presents and summarises the important technical issues that enhance the adoption of this technique for the Malaysian built environment.

Effective use of hybrid turbine ventilator to improve thermal performance in Malaysian tropical houses

An efficient design approach that involves extracting heat build-up in tropical buildings is a means to reduce total dependency on air-conditioning systems. The hybrid turbine ventilator can be regarded as a development technique to address this issue. However, identifying its efficient application in buildings remains questionable. This study aims to develop the research on the hybrid turbine ventilator for the establishment of energy-efficient designs in houses by evaluating its effective use in specific space volume based on several empirical comparisons. The performance of passive and hybrid turbine ventilators in attic space, room, and (attic space + room) with opened and closed windows was compared. The study was conducted in an actual building model, and data were collected onsite with a data acquisition system. The objective was achieved by investigation, and the findings can be used to identify the levels of heat build-up in each strategy. Examination of thermal performance confirmed the appropriate use of the hybrid turbine ventilator in Malaysian landed houses. Practical application :This research contributes directly to energy efficient design in tropical buildings. The outcomes inform a better decision on the effective use of hybrid turbine ventilator in low-rise buildings. The study provides ample evidence on the great potential of using hybrid turbine ventilator by developing its investigation in tropical architecture. The study will assist engineers and architects to evaluate hybrid turbine ventilator performance effectively.

Toplighting Systems for Improving Indoor Environment: A Review

Toplighting systems represent an optimum source of natural light for building interiors. These systems provide abundant illuminance levels from small openings, thus reducing artificial lighting and minimising glazing areas. However, based on a geographic location, these systems transfer high sunlight levels, which directly affect the performance of indoor environment. Therefore, studying their potentials requires proper understanding. The aim of this research is to emphasise the critical design concepts in different places and provide an indication of the characteristics of these global system designs. The method of this study is theoretically based on descriptive analysis to assess design requirements. This study includes a discussion on different methods and standards, which deeply and systematically deliberated several trends such as comparative benefits and limitations. This chapter presents a holistic view of selecting toplighting systems during the design stage, which makes the review a useful source for architects, building designers, and practitioners.

Energy Efficient Skylight Design in Tropical Houses

Skylight roofing construction isa practical complement to electric lighting even in various climatic conditions. However, a purely energy efficient building that ignores what the environment can contribute, particularly in tropical regions, will consume more energy. This problem can be found in landed houses specifically in Malaysia due to high impact of solar radiation and the length of the daylight period all year round. The lack of understanding the potential of skylight design is one of the main challenges. This paper aims to examine several passive glazing materials in the form of glass and plastic as well as dimensions and orientations under the Malaysian environmental conditions to determine the efficiency of this skylight construction design. The study was carried out by computer simulation to specify the thermal and daylighting loads in a specific room size. The resultsshow the significance of polycarbonate glazing as an efficient skylight material in the tropical houses. This materialdelivers well distributed natural light with less heat impact. This study provides useful quantitative and qualitative information for building professionals and architects in the tropics.

Solar Induced Ventilation Strategy in Contemporary Tropical Buildings: A Review

Recent development in passive cooling studies have shown that stack ventilation could be a potential strategy in providing effective natural ventilation strategy for a building in the windless region, and in the deep plan building where cross ventilation has limited function. However for the building in tropical climate where the indoor–outdoor temperature differential is very low, this strategy is often regarded insignificant to provide sufficient ventilation needed for occupants comfort. This constraint has prompted several researchers to develop some solar induced ventilation strategies that can maximize free energy available from the sun and high solar radiation of tropical climate to heat building cavities and increase the temperature difference, thus improving the applicability of the stack ventilation strategy in suctioning the indoor air and extracting it out through the upper outlet areas. This book chapter presents the potential and limitations of the solar induced ventilation strategy in the tropical region, particularly in its subtypes of tropical rainforest climate and tropical monsoon climate by discussing its ventilation performance based on the results of previous studies, state-of-the art technologies and several significant examples of its applications in the contemporary tropical buildings.

Daylighting Tropical Building Interiors from Skylight: The Case for Separating Heat from Useful Visible Light

Daylighting in modern architecture affects space arrangement, user’s visual and thermal comfort, and building energy use. It is the highest quality light source. Tropical countries suffer from high solar insolation that brings in heat and glare. The gradual increase in the energy cost in tropical countries, as in Malaysia, challenges the building designer to rethink the construction of the skylight system as a strategy to reduce the environmental impacts on indoor conditions. The solution is not as simple as those achieved in the temperate countries. This paper investigates the possibility of using the roof light as an acceptable tropical design element that can meet the requirements of Malaysian Green Building Index. Initial computer simulation was carried out before collecting empirical data. The hypothesis has been achieved to provide a better indoor daylight comfort, but several factors to be considered and modified are discussed. All these adjustments are to meet the Malaysian Comfort Temperature.

The Creation Of An Eco-tourism Site:A Case Study Of Pulau Singa Besar

Ecotourism is the fastest growing form of tourism in Malaysia. It currently makes up about 10% of the country’s tourism revenue. The Malaysian Government, specifically the Minister of Culture, Arts and Tourism has adopted a National Tourism Policy and National Ecotourism Plan (1996–2005) to encourage visitation to rural areas in order to enhance economic development as well as to meet the demands of what was perceived to be increased interest in the natural heritage of the country by the international tourism market. The development of Pulau Singa Besar, a small island off the legendary and more famous Langkawi Island in Malaysia is among one of the many efforts. The importance of sustainable planning, design and management is critical if an ecotourism site is to continue in generations to come. This paper addresses fundamental issues in the planning, design and implementation of various projects on the island of Pulau Singa Besar. It focuses on the lessons learned for