Ibrahim Hussein

Reconnaissance studies of micro hydro potential in Malaysia

Malaysia is blessed with abundant streams and rivers flowing from highland areas, thus promise it with a lot of hydro power potential. To date Malaysia had utilized these potential in the range of large and mini hydropower but very few in the micro hydro range. This paper presents the results of reconnaissance studies carried out to identify the micro hydro potential sites in Malaysia. The reconnaissance studies were conducted with data from the Department of Survey and Mapping Malaysia, (JUPEM) and Metrological Department Malaysia. All the identified streams were located in areas which are accessible and/or showed evidence of settlements. Only streams with high head i.e. above 50m, were considered in this study. From the reconnaissance studies, a total of 149 sites were identified. However, the energy demand for micro hydro was found not significant as most areas in Malaysia are electrified. Still, micro hydro generation may serve as alternative renewable energy source in future amid rising electricity cost.

Micro hydro potential in West Malaysia

Combination of highland areas with huge river networks promise Malaysia with a lot of hydro power potential. To date Malaysia had utilized this potential in the range of large and mini hydropower but not in the micro hydro range. Micro hydro refers to power generation in the range of 5kW to 100kW. Micro hydro can provide alternative renewable energy sources especially in areas with small rivers or streams flowing. In identifying the micro hydro potential sites, reconnaissance studies is normally conducted. It is a preliminary study to identify micro hydropower potential. This paper presents the results of reconnaissance studies carried out to identify the micro hydro potential in West Malaysia. The reconnaissance studies were conducted with data from the Department of Survey and Mapping Malaysia, (JUPEM) and Metrological Department Malaysia. All the identified streams are located in areas which are accessible and/or showed evidence of settlements. Only streams with high head i.e. above 50m were considered in this study. From the reconnaissance studies, a total of 109 sites having micro hydro potential of about 20.4MW were identified. However, the energy demand for micro hydro was found not significant in West Malaysia as most areas are electrified. Still, micro hydro generation may serve as alternative renewable energy source in future amid rising electricity cost.

An experimental investigation of pump as turbine for micro hydro application

This paper presents the results of an experimental investigation of a centrifugal pump working as turbine (PAT). An end suction centrifugal pump was tested in turbine mode at PAT experimental rig installed in the Mechanical Engineering Laboratory of Universiti Tenaga Nasional. The pump with specific speed of 15.36 (m, m3/s) was used in the experiment and the performance characteristic of the PAT was determined. The experiment showed that a centrifugal pump can satisfactorily be operated as turbine without any mechanical problems. As compared to pump operation, the pump was found to operate at higher heads and discharge values in turbine mode. The best efficiency point (BEP) in turbine mode was found to be lower than BEP in pump mode. The results obtained were also compared to the work of some previous researchers.

Field studies on thermal comfort of air-conditioned and non air-conditioned buildings in Malaysia

Field studies on the environmental conditions and occupant comfort were carried out in air-conditioned buildings and non air-conditioned buildings in Malaysia. The study on the air-conditioned buildings was carried out in UNITEN and for the non air-conditioned buildings in two schools, which is a primary and secondary school, and in a public waiting area in a health clinic in Johor Bahru, located in the southern region of Malaysia. The non air-conditioned buildings were mechanically ventilated by fans. The studies were made in different days from morning until noon as to get variation of temperatures, collecting a full set of objective physical measurements and subjective assessments through questionnaires. The measured environmental parameters were air temperature, relative humidity and air velocity. The subjective responses concern the judgment of the respondents about the thermal environment at the moment of measurements. The results obtained showed that majority of the respondents found that their indoor thermal conditions acceptable even though most of the thermal sensation votes (TSV) exceeded those specified by ASHRAE Standard 55 and the environmental assessments exceeded the standard. The neutral temperature and comfort range were obtained through linear regression analysis of TSV and in the Fangers PMV model. From the subjective assessment, it was found that the occupants can accept the thermal range beyond the ASHRAE comfort zone. The neutral temperature of 24.4°C and 28.4°C for air-conditioned and non air-conditioned buildings respectively, were obtained by regression analysis of TSV on operative temperature. The acceptable range of temperature obtained by regression analysis of TSV were 23.1°C to 25.6°C for air-conditioned buildings and 26.0°C to 30.7°C for non air-conditioned buildings.

Performance and emission investigation of a four-stroke liquefied petroleum gas spark-ignition engine generator used in a Malaysian night market

Abstract The objective of this study is to investigate and compare the performance and emission characteristics of the liquefied petroleum gas (LPG)-fuelled engine generator and the conventional gasoline-fuelled engine generator. The approach involves converting a gasoline engine generator, commonly used in Malaysian night markets to generate electricity, to the LPG engine generator. A four-stroke SI single-cylinder engine is equipped with an LPG injection system with minor modifications and then tested with both LPG and gasoline fuels. A venturi mixer (carburettor) was designed and in house constructed and then installed to deliver a proper A/F ratio to the combustion chamber. The commercial computational fluid dynamics software FLUENT was used for simulation of air flow inside the mixer. The converted engine was tested at constant speed for its brake-specific fuel consumption (BSFC), efficiency, exhaust temperature, and exhaust gas emissions. The results show that the performance and emission characteristics of the LPG-fuelled engine are well suited for use in night markets. Average BSFC and average efficiency for the LPG engine over a range of loads were quite similar to those for the gasoline engine: the average BSFC was 0.95 kg/kWh for the LPG engine and 1 kg/kWh for the gasoline engine. The use of LPG as fuel in a gasoline engine causes only a slight reduction in efficiency as a 17 per cent reduction in average efficiency was recorded over the entire load range; however, the LPG engine fared better at higher loads than the gasoline engine for which only as low as a 4 per cent reduction was recorded at high loads. Emission tests seem to verify the minimal pollution products; there are significant reductions in the emission concentration results when LPG is used. Average decreases of 32 per cent for nitrogen oxide, 10 per cent for carbon dioxide, and 40 per cent for carbon monoxide were recorded. Although higher values of hydrocarbon (HC) were recorded, a 50 per cent reduction in HC was found for loads higher than 700 W. The study verified the more favourable features of LPG compared to gasoline as it is one of the best alternative fuels to gasoline for spark-ignition engine generators to solve the air pollution problem in night markets.

Preliminary study on combustion of biodiesel for power generation

In the recent wake of escalating crude oil prices due to depletion of fossil fuel, biodiesel has generated a significant interest as an alternative fuel for the future. The use of biodiesel to fuel microturbines or gas turbine application is envisaged to solve problems of diminishing supplies of fossil fuel reserves and environmental concerns. This paper examines the combustion of biodiesel derived from Malaysian Waste Cooking Oil (WCO) in a combustion test facility to study the feasibility of using the designated fuel at five various volumetric ratios for gas turbine application. Biodiesel was produced from waste cooking oil in Malaysia, mainly from palm oil sources and animal fats. The oil burner was able to fire the five blends of fuel without any modification or pretreatment. The combustion performance of Malaysian WCO biodiesel and distillate blends was examined with respect to the combustion efficiency. The results indicated biodiesel combustion required less air for stoichiometric combustion due to presence of oxygen in the fuel. Indeed biodiesel stand as a potential alternative fuel for power generation application with the best efficiency at blended ratio of 20% biodiesel and 80% distillate.Copyright

Analysis on Thermal Comfort of Air-Conditioned Buildings in Malaysia: Case Study of Universiti Tenaga Nasional

Field study was carried out on the thermal conditions and thermal comfort of occupants in air conditioned buildings in Malaysia. The study was carried out in 10 staff offices and 6 student study areas of Universiti Tenaga Nasional (UNITEN) during October and November 2013, collecting a full set of objective physical measurements and subjective assessments through questionnaires. The measured environmental parameters were air temperature, relative humidity and air velocity. The subjective responses concern the judgment of the occupants about the thermal environment at the moment of measurements. The obtained results showed that most places are in acceptable and comfort zone according to Fanger’s predicted mean vote (PMV) model. The neutral air temperature obtained through linear regression analysis of thermal sensation vote (TSV) is 23.9°C for UNITEN. The result of this study demonstrates that the acceptability of thermal comfort among UNITEN occupant is about 78 %.

Effectiveness of Computerized Homework Implementation in Thermodynamics: Correlation Between Doing the Homework and the Grade

The objective of the implementation is to gauge the effectiveness of computerized homework in improving students’ understandings of Thermodynamics, and to investigate the correlation between the scores attained in computerized homework and the overall grade achieved by the students in Thermodynamics. There were two sections of MEHB213 Thermodynamics I offered during Special Semester 2013/2014. Section 1 with 63 students used the computerized homework while the other section (Section 2, 60 students) continued with the normal manual homework. The computerized homework did not utilize the commercial software available in the market, instead it was developed at College of Engineering, UNITEN. The computerized homework system is a MATLAB and PHP based program and resides on Apache Web server. MATLAB generates the questions and randomize the variables, while PHP displays the contents on the web. The database used for the system is MySQL. The manual homework assigned for the subject had been replaced by the computerized homework in order to give a fast feedback to the students and to reduce the time engaged by lecturers to mark the homework. The answers submitted by students in computerized homework were automatically graded by the system, and they would be immediately notified whether the answers given were correct or not. The students could access the computerized homework at anytime throughout the semester. The questions were arranged according to chapters and the time to release each question could be set in the system. The result from this study shows there is a direct correlation between doing the computerized homework and the improved grades in Thermodynamics I. 90.4 % of students from Section 1 who used the computerized homework passed the subject while the section which did not use the system had 56.7 % passing grade.