Showing papers in "International Journal of Renewable Energy in 2011"

Potential use of solar photovoltaic in Peninsular Malaysia

Abstract: Energy is important to all aspects of development to support population growth, urbanization, industrialization as well as tourism industry. The energy consumption is also increasing and several alternative green energy sources are seriously taken into consideration to fulfill Malaysia's energy demand. The Malaysian government has looked into the renewable energy (RE) sources such as solar energy to be one of the alternatives to face problems related with the increase in energy demand. However, the heavily subsidized of non renewable sources in the country has made the RE sources an uneconomical option. The aim of this paper is to briefly review about incentives and the RE Act adopted by the Malaysian government to ensure long term reliability and security of energy supply. The feed-in-tariff system, solar radiation intensity in Peninsular Malaysia and the role of renewable energy sources in the Five-Fuel Diversification Strategy energy mix are also highlighted in this paper.

Study of renewable energy potential in Malaysia

Abstract: Malaysia has many renewable energy sources that can be developed such as solar, wind, biomass, hydro, geothermal and tidal wave. However, it is not yet widely developed. Since, energy is important, a national center for renewable energy resources database should be setup to bring together designers, engineers, architects and policy makers to use the actual data for implementing renewable energy projects. The objective of this study is to determine the most suitable renewable energy generation to be implemented in Malaysia from four obvious options available which are solar, wind, biomass and tidal wave. A study has been conducted in several contributing factors namely geographical distribution, technology involved and economic analysis. The analysis has been done by gathering the related information and data from previous studies as well as and visits to sites and related authorities. The result of these analysis shows that biomass energy generation has the most encouraging potential to be developed in Malaysia as shown by evidences from the comparative study being made in this paper.

Design analysis of low-pass passive filter in single-phase grid-connected transformerless inverter

Abstract: Presented is the design analysis of a single-phase grid-connected photovoltaic-inverter low-pass-output filter. It minimizes switching-frequency current harmonics, improving output response. The inverter is H-Bridge transformerless. Switching frequencies 8Hz, 14kHz, and 20kHz were compared for validation of the simulation and the experiment.

Economic and environmental emissions analysis in Indonesian electricity expansion planning: Low-rank coal and geothermal energy utilization scenarios

Abstract: This paper examines utilization of low-rank coal and geothermal energy resources in the long-term Indonesian electricity expansion planning in high populated islands Java, Madura, and Bali up to 2027. The long-term electricity expansion of these areas meets several problems such as supply security, financial limitation, and environmental issues. Therefore, the modeling of long-term geothermal and low-rank coal utilization is examined in terms of expansion cost as well as the environmental impacts. In 2027, the required capacity to fulfill future demand is estimated 133 GW. Under the coal scenarios, the domination of coal becomes bigger with 75.4 GW or 57% of total electricity generation mix. However, under the geothermal scenarios, the installed power plant form geothermal sources increase to be 7 GW and coal utilization decreases to be only 67.6 GW or 51% of total electricity generation share. In the economic perspective, more geothermal power plant need to be developed in order to reduce to coal utilization in power generation. In the end of planning horizon, the coal scenario emits as much as 487 million tons of CO2 equivalents, while the geothermal scenario successes to reduce emissions by 43.3 million tons from the coal scenario's emissions.

Energy performance: A comparison of four different multi-residential building designs and forms in the equatorial region

Abstract: Building sector has been identified as a major energy consumer with nearly half of the world's energy used is associated with providing environmental conditioning in buildings. Approximately, two third of this is for heating, cooling and mechanical ventilation. Therefore, there is a need for optimizing the building design which collaborates with surrounding environment in enhances the energy conservation programme. Energy consumption evaluation and audits for buildings is the most important step that can contribute to energy conservation. As preliminary studies to this research, four low-rise residential college buildings with specific layout were selected in finding the relationship between green/passive building strategies and energy performance. The study initial approach was to critically analyse the design of the selected buildings through scaled drawings and site visits. Comparison of the two were carefully made to obtain current and post renovation conditions and surroundings as most of the drawings were drawn 30 to 40 years back. The elements of bioclimatic design were implemented as matrixes or criteria, particularly on natural ventilation and day lighting. Then, the energy performance was crucially audited to find out Building Energy Performance (BEP) acknowledged as energy use per unit floor area, and Energy Efficiency Index (EEI) to elaborate the kWh/m2/year of each residential college for five years duration. As initial findings, the implementations of appropriate green building strategies is able to provide positive impacts to the overall energy performance of the residential colleges.

Thermogravimetric analysis of palm oil wastes decomposition

Abstract: Thermal decomposition of palm oil wastes i.e. palm kernel shell (PKS) and palm oil fronds (POF) was studied using thermogravimetric analysis (TGA) under non-isothermal conditions. Thermogravimetric (TG) and its first derivative profiles were depicted to show different breakdown regions for PKS and POF. The decomposition region of hemicellulose, cellulose and lignin was identified. Kinetic parameters i.e. activation energy, pre-exponential factor and order of reaction were then evaluated from the profiles for the temperature range of 50–900°C at a heating rate of 20 °C/min. Nearly 60 wt% of palm oil wastes decomposed at the temperature less than 400 °C. The thermal decomposition of palm oil wastes fitted well as first order kinetics with correlation coefficient of R2 > 0.99. The activation energy of PKS and POF was 35 and 41 kJ/mol, respectively. This fundamental study provides the basic information on palm oil wastes decomposition which can benefit our current development work on palm oil wastes steam gasification unit.

Life cycle assessment of palm oil biodiesel production in Thailand

Abstract: Biodiesel from palm oil has been considered for partial substitution of diesel fuel for transportation in Thailand. The Government of Thailand recently has set up a production target of 8.5 million liters per day of palm oil-based biodiesel by 2012. Generating biodiesel from palm oil requires a great amount of materials and energy, and during the production process several kinds of emissions are released which adversely affect the environment. Therefore, to quantify and verify the advantages and usefulness of palm oil biodiesel, it is necessary to assess its production from a life cycle point of view. The objective of this paper is to analyze the environmental impacts of palm oil biodiesel from a life cycle assessment (LCA) aspect. The SimaPro software scheme was applied in this study. This study will consider the environmental impacts from 1 liter of palm oil biodiesel; the study is divided into three processs: agriculture, transesterification into biodiesel, and utilization. The agricultural, palm oil production and biodiesel production (transesterification) facilities are all located in Krabi province, in the southern part of Thailand. EDIP method and European databases included in the LCA software SimaPro have been used for the impact calculations. The results of the study show the environmental impact per liter of palm oil biodiesel. This study indicates that the ustilization process has the greatest environmental impact, 52.09% of the total. Next are the production of biodiesel and agricultural procedures, amounting to 41.21% and 6.7%, respectively. The most significant impacts from the system are ozone formation, terrestrial eutrophication, aquatic eutrophication, and acidification. The environmental impacts take place from the emissions of CO and NO2 during combustion.

Physico-chemical properties of palm oil fuel ash as composite sorbent in kaolin clay landfill liner system

Abstract: This paper presents the physico-chemical properties of palm oil fuel ash (POFA) a biomass residue, while justifying its use as composite sorbent when admixed with kaolin clay, for the purpose of designing composite sanitary landfill liner. Laboratory analysis conducted centered on properties of sundried raw POFA passing through 150µ, 75µ, 38µ test sieves, and of the fine ground ash to 27µ , after mechanical homogenization of retained ashes. Physical analysis conducted includes particle size distribution and density tests for blended ash. Chemical tests include Energy Dispersive X-Ray Analysis (EDX), for elemental compositions, with particular interest in exchangeable metal cations and background concentration of selected toxic heavy metals. Tests also include X-ray Fluorescence (XRF), for bulk chemical components, specific surface area(SSA), from Particle size analyzer (PSA), scanned electron microscope(SEM), for morphological structure of retained and ground ash samples, mass loss on ignition (LOI), at 440 ± 25 °C, for a period of 4 h. Primary factors affecting variable charge ions at edges of kaolin clay is pH, thus, was also determined as hydrogen ion concentration in POFA-aqueous environment. Material sourcing and pretreatment technology were reported. Silica oxide (SiO2), present in ground ash via XRF was found to be 53.20%, while summation of SiO 2 , Al 2 O 3 , and Fe 2 O 3 present was 69.80%. Inherited calcium oxide (CaO-lime) was 9.73%. Exchangeable cations present are Na2+, K2+, Ca2+ and Mg2+. Structural and appearance analysis shows that ground POFA was amorphous. From these properties inferences were drawn on expected chemical reactions from POFA, and when both materials are blended for the design of composite sanitary landfill liner. This novel material is hoped to provide a more efficient trapping mechanism of toxic heavy metals ions in leachate, when compared with single liner material from kaolin clay. Conclusively, POFA a bio-sorbent could be suitably used as composite sorbent for improvement of kaolin clay designed as component of engineered sanitary landfill liner.

Prospect of hydrocarbon uses based on exergy analysis in the vapor compression refrigeration system

Abstract: This paper emphasized on the possibilities of researches in the field of exergy analysis in various usable sectors where vapor compression refrigeration systems are used. Exergy losses, exergy efficiency, second law efficiency and irreversibility of the system components as well as of the whole system are measured. In the vapor compression system, R134a, R290 and R600a are considered as refrigerants. Exergy parameters in the compressor, evaporator, condenser and expansion devices are calculated and analyzed. Exergy losses depend on evaporator temperatures, condensing temperature, refrigerants and ambient temperature. Most of the exergy losses occur in the condenser. Expansion device has the lowest losses. Exergy parameters are compared for different operating temperature. It is found that hydrocarbons (R600a) have 50% higher exergy efficiency than R134a. Mixture of hydrocarbons also shows the best performance based on the exergy analysis.

Heat extraction from gradient layer using external heat exchangers to enhance the overall efficiency of solar ponds

Abstract: A salinity gradient solar pond is a combined solar collector and thermal energy storage system, and in past heat has been successfully extracted from the lower convective zone (LCZ) in working ponds. This paper discusses possibility of heat extraction from the non convective zone (NCZ) using an external heat exchanger. Here, two methods of heat extraction from different levels within the NCZ using external heat exchanger are presented. The first method uses thermosyphon effect to transfer the heat from different levels in NCZ to the binary fluid. The second method uses pumps (forced convection) for heat extraction. This paper presents theoretical modeling and experimental results for thermosyphon based heat extraction method. Later theoretical predictions and experimental results have been compared. This investigation shows good prospects for application of this system for heat extraction from NCZ of large solar ponds. By extracting heat from the NCZ the efficiency of a solar pond could be increased up to 30%.

Utilization ultrasonic to increase the efficiency of oil extraction for microalgae indigenous isolates from pond gresik, east java

Abstract: The prospect of microalgae biomass as biodiesel is a renewable energy to substitute for petroleum. Identification of microalgae indigenous from Gresik ponds, East Java are 29 species, and at Biological laboratory, Science Faculty, UM was able to isolate 10 species. Among the isolated, there are 2 species that faster growth rate, Chlorella vulgaris and Spirogyra sp. Generally, extraction of oil from microalgae biomass requires a long time. The aims from the research are to examine three methods of oil extraction from the two species of microalgae, the experimental laboratory techniques. Biomass of microalgae dry powder was extracted using the solvent n-hexane by three methods, Soxhlet, maceration and ultrasonic waves. On the acquisition of microalgae oil the yield equivalent, compared with extraction time from the three methods. The smaller time of microalgae oil extraction is the more efficient extraction. The results showed: (1) The use of ultrasonic waves can improve the efficiency of microalgae oil extraction. (2) The yield of algae oil which is extracted using the method Soxhlet, maceration, and extraction with the aid of ultrasonic waves in a row is 1.58%, 1.03%, and 1.77% by the time it takes for 18 hours, 8 hours, and 2.33 hours.

Average photon energy under Thailand’s climatic condition

Abstract: This paper presents seasonal spectral solar irradiance distribution variation under Thailand’s climate. The annual spectral solar irradiance distribution measurement at Energy Park, School of Renewable Energy Technology (SERT), Naresuan University, Thailand showed that the maximum frequencies of solar irradiations were in the ranges 420-710 W/m 2 , i.e., blue rich range or visible light. The maximum frequencies of photon flux densities calculated were in the ranges 3.40x10 17 –5.30x10 17 photon/m 2 s. The average photon energy (APE) values were found to be 1.92 eV, 1.90 eV and 1.84 eV in summer, rainy and winter seasons respectively. The annual spectral irradiance measurement data showed that APE of total incident solar irradiance was 50% higher than that of the AM 1.5 standard solar spectrums. These results indicate that the wavelength is influence of photon flux density.

Deadbeat-based PI controller for stand-alone single-phase voltage source inverter using battery cell as primary sources

Abstract: This paper presents a deadbeat-based proportional-integral (PI) controller for stand-alone single-phase voltage source inverter using battery cell as primary energy sources. The system consists of the lead acid battery, third order Butterworth low pass DC filter and AC filter, H-bridge inverter, step-up transformer, and also a variety of loads as well as its sinusoidal pulse-width-modulation (SPWM) deadbeat-based PI controller. In this paper, two simulation case studies have been carried out which are the abrupt load changes from 400W resistive load to 500W resistive load and also from 400W resistive load to inductive load of 500W 0.85 power factor lagging. From the simulation results for both cases, the state-of-charge (SOC) battery is decreasing to supply power to the different type of loads, yet the battery voltage remains constant at about 36V and also the battery current exhibits smooth ripple despite current spikes produced by the H-bridge inverter so as to prolong the lifespan of the battery. It shows that the DC filter performs satisfactorily to isolate the current spikes generated by the SPWM controller and H-bridge inverter. Besides that, even though the load varies for both cases, the sinusoidal inverter output voltage can be tracked and maintained at 230V rms with 50Hz frequency within few cycles from the instant the load changes as well as low THD v content of 1.53% and 2.78% respectively. This indicates that the controller proves its robustness and stiffness characteristic in maintaining the output load voltage at desired value to supply the power for variety of loads with minimum THD v .

Syntheses, characterizations and testings of carbon nanofiber for hydrogen adsorption studies

Abstract: Renewable energy (RE) has been declared as the fifth fuel of Malaysia in addition to oil, gas, coal and hydropower. One of RE which is hydrogen and has became an alternative fuel for transportation instead of petroleum. For sufficient hydrogen storage, the system requires an inexpensive, safe, low weight tank, comparable in to a gasoline tank with capability of quick loading and unloading hydrogen fuel. Carbon nanomaterials have been nominated as one of the best medium to store hydrogen due to its light weight, low cost production depending upon types of synthesis methods, non-toxic and can be generated with improvement in its storage capacity. The research work focuses on the development of graphitic nanofibers by using chemical vapor deposition method. The development of catalyst which was iron (III) oxide and nickel (II) oxide for the synthesis of graphitic nanofibers has also been investigated. The capacity of the developed materials in hydrogen adsorption is tested at 298K and the pressure up to 100 bar using gravimetric measurement technique. Sample imaging observations using field emission electron microscopy (FESEM) and transmission electron microscopy (TEM) indicate that the synthesized graphitic nanofibers (GNFs) have both platelet and herringbone structure with little carbon nanotubes (CNTs). Iron-based catalyst GNF (FG) samples have diameter size of 170 nm while nickel-based catalyst GNF (NG) has diameter size of 200 nm. Specific BET surface area of FG and NG are 92.34 m2/g and 45.96 m2/g, respectively. Both analysis which are energy-dispersive X-ray (EDX) and thermogravimetric proved that purity of FG is between 88% to 95% while purity of NG is ranges from 95% to 97%. For iron-based catalyst GNF, the highest uptake is 0.46wt % at 70 bar and for nickel-based catalyst GNF, the highest uptake is 1.7611wt % at 70 bar.

Fatty Methyl esters from vegetable oils for use as a diesel fuel

Abstract: The world is confronted with the twin crisis of fossil fuel depletion and environmental degradation. The indiscriminate extraction and consumption of Fossil fuels have led to a reduction in petroleum. Due to the concern on the availability of recoverable fossil fuel reserves and environmental problems caused by the use of those fossil fuels, considerable attention has been given to biodiesel production. The methyl esters of vegetable oils, known as biodiesel becoming increasing popular, because of its potential as a green alternative fuel for diesel fuel. It has many advantages over conventional diesel fuels. These include biodegradable, non toxic, nil sulfur content, reduced aromatics. It can either be directly used in engine or can be blended with conventional diesel, and requires no engine modification. There are various methods available for the production of biodiesel such as micro emulsification, dilution, pyrolysis, transesterification and esterification, among which transesterification is the best process. Biodiesel is produced by transesterifying the parent oil or fat with an alcohol, usually methanol, in presence of a catalyst usually strong base such as NaOH or KOH or, preferably an increasingly more commonly alkoxide. The transesterification reaction variable that affect yield and purity of the product include molar ratio of alcohol to vegetable oil, type of catalyst, molar ratio of catalyst to oil, temperature and degree of refinement of vegetable oil. In this paper various vegetable oils transesterification was studied with the purpose of achieving the best conditions for biodiesel production.

Velocity and Temperature Distribution of Flowing Water in a Solar Parabolic Trough Receiver

Abstract: This paper focuses on the determination of the velocity and temperature distribution for water flow in a parabolic trough receiver by using simulation technique. In order to determine the velocity and temperature distribution of water flow through this receiver, the velocity of a normal and parallel direction of water flow, the relationship between the water’s mass flow rate and the temperature of water while flowing trough the receiver pipe are determined. The methodology of this study is based on solving partial differential equations by using finite difference method of mass, momentum and energy conservation. This method applies a Power law model to momentum equations and applies a central difference model to energy equation. The set of discretization equations are solved simultaneously by “SIMPLE” algorithm to obtain velocity and temperature distribution within the receiver.

A numerical model for the simulation of double-diffusive natural convection in a right-angled triangular solar collector

Abstract: A numerical model is presented for the simulation ofdouble-diffusive natural convection in a triangular solarcollector. This design is encountered in greenhouse solarstills where vertical temperature and concentrationgradients between the saline water and transparent coverinduce flows in a confined space. This phenomenonplays an important function in the water distillationprocess and in the biological comfort. In this doublediffusion problem, the ratioBr of the relative magnitudethermal and compositional buoyancy and Rayleighnumbers are key parameters. Finite element technique isused to solve the governing equations. Numerical resultsare presented for the effect of the abovementionedparameters on local heat and mass transfer rate. Inaddition, results for the average heat and mass transferrate are offered and discussed for the mentionedparametric conditions. Some interesting results are foundin this investigation.

Development of energy conservation programs for residential and small commercial buildings in Thailand

Abstract: This study examines various scenarios of the energy consumption trends of the residential and small commercial buildings in Thailand. It is expected that without implementing any energy conservation measures, the consumption of these sectors will increase about two folds from the present (2010) in next twenty years (2030). Although the consumptions by the main activities i.e. lighting, cooking, entertainment reach saturation, the increase of units of air-conditioners and electric water heaters in the buildings results in dramatic electricity consumption.

Electrospun metal oxides nanostructures for energy related devices

Abstract: Metal oxide nanostructures of wide bandgap semiconductors with various morphologies, high degree of crystallinity and surface properties were fabricated by electrospinning a polymeric solution containing respective metal ions and their controlled heat treatment. The metal oxide nanostructures thus developed were tested for their application as charge separation and transport medium in solar cells, cathodes for low voltage (2 V) lithium ion batteries, and super capacitors. The solar cells thus fabricated features enhanced electron diffusion coefficient and energy storage devices featured stable electrochemical cycling thereby making electrospun metal oxide nanostructures a viable product for next generation energy industry.

Industrial and adaptable components for building waste reduction

Abstract: One of the main concerns of environmental sustainability is to reduce the depletion of valuable materials and natural resources. To do so, construction waste management needs to be considered in the early stages of building components design and preparation. Industrial, Flexible and Demountable building system (IFD) is attempting to create more adaptable buildings while managing its end-of-life more efficiently and focusing on the long term performance of structure and materials. It will assist the main concept of sustainability by reducing material and energy consumption as well as environmental pollution. This research focuses on the development of IFD system for residential terrace house layout. Proposing a procedure to evaluate the conceptual prototype is the key concern. The procedure contains assessment according to IFD criteria and structural characteristics. ETABS software was applied for analyzing the stability and load bearing capacity of the structure. The assessments have testified to the flexibility and strength of the designed layout. Findings from this study have implications for construction industry who concern environmental sustainability as well.

Oil Press for Food Oil and Biomass Production

Abstract: In this study, first, rapeseed was separated the high quality seed for food oil and the low quality seed for biofuels. Next, laboratory-scale oilseed screw press was used to investigate the effects of choke opening and seed preheating on these rapeseed pressing performance and quality of food oil and biofuels oil. Maximum pressure increased, oil recovery increased, but chlorophyll in rapeseed oil was increased, too. Especially, acid value of the rapeseed oil extracted from low quality seed was high value. For the rapeseed pressing performance, the rapeseed heated by microwaves outputted more oil than that without heating. And the chlorophyll in the rapeseed oil extracted from the rapeseed treated by microwaves was higher than that without heating. The Net Energy Balance ratio of microwave heating press with choke opening set at 8.0 mm is advantage. And the oil pressed this method was good and basically fulfilled the Codex Alimentarius requirements for edible oils.

Investigation of buffer layers, front and back contacts for Zn x Cd 1−x S/CdTe photovoltaic

Abstract: A numerical analysis has been performed utilizing Analysis of Microelectronic and Photonic Structures (AMPS 1D) simulator to explore the possibility of higher efficiency and stable Zn x Cd 1−x S/CdTe cells. Several cell structures with indium tin oxide (ITO) and cadmium stannate (Cd 2 SnO 4 ) as front contact, zinc stannate (Zn 2 SnO 4 ) and zinc oxide (ZnO) as buffer layer and antimony telluride (Sb 2 Te 3 ) insertion with Nickle (Ni) as back contact has been investigated in the conventional (SnO 2 /CdS/CdTe/Ag) CdTe cell structures in which CdS is replaced by zinc cadmium sulphide (Zn x Cd 1−x S) as window layer. Efficiency as high as 18.0% has been found with 80 nm of Zn x Cd 1−x S window layer for x=0.05, 1 µm of CdTe layer and 100 nm Zn 2 SnO 4 buffer layer without Sb 2 Te 3 back contact. However, ZnO insertion shows low conversion efficiency of 7.84% and 12.26%, respectively with and without Sb 2 Te 3 back contact. It has been found that 1 µm of CdTe absorber layer, 70 nm of Zn x Cd 1−x S (x=0.05) window layer, 100 nm of Zn 2 SnO 4 buffer layer and 100 nm Sb 2 Te 3 back contact layer are sufficient for high efficiency (>17.5%) Zn x Cd 1−x S/CdTe cells. Moreover, it was found that the cell normalized efficiency linearly decreases with the increasing operating temperature at the temperature gradient of −0.25%/°C.

Alternative Utilizations of Photovoltaic Modules from Solar Home System, Thailand

Abstract: Since, the SHS program started in year 2003, approximately 200,000 units of SHS have been installed. Unfortunately, many survey studies indicated that more than 20 percent of SHS were not working properly, due to damages of system components such as, battery, charge controller, inverter, and lighting system, but, almost of PV modules are working perfectly. So, this paper presents a practice to recover the potential of PV modules, which have been abandoned. The paper describes alternative utilizations of PV modules, including photovoltaic stand alone system (PVSS), photovoltaic hybrid system (PVHS), and photovoltaic grid connected system (PVGS). This paper also describes about alternative system selection guideline and the system advantages. In 2009, Tambon Shomphoo, which located in Nernmaprang district, Phisanuloke province, has been selected as a study site. From the survey data show that there were about 20% of SHS was malfunction or 114 PV modules or 14 kWp of alternative system was available. The PVSS was selected from the alternative system guide and economic of the system was assessed. The system can produce 18,391.90 kWh/y. The life cycle cost is about 3,222,430Bath and COE is 8.76 Bath/kWh.

Community acceptance of nuclear power generation in Japan and relevant influencing factors

Abstract: Acceptance for NPP in Japan was approximately supported by half of the population. This was composed by 11% in favour of expansion and 42% in favour for at least maintaining the current plants in operation. In comparison to previous reports, there is virtually no change in the percentage of those supporting NPP expansion but the remaining have shifted to a more sceptical or opposed view towards NPP.

Improving Quality with Seasonal Rice Propagation for Production by Protein SDS-PAGE Combined with Classical Technique

Abstract: One of the main reasons that have caused constraints for development of Makapuno plantation in Mekong delta was embryo to be very difficult to germinate in natural condition. Farmers have not known how to propagate this plant. Thus results obtained from farmers are not high. With experiences, farmers collected nuts from bunch which bore Makapuno fruits. Then they sowed all nuts in shading and wet places until seedlings developed and obtained 5-6 leave; after that they planted seedlings in gardens with other trees such as mangoes, durians, tamarinds, rambutans, star apples…Consequently, coconut trees bore less than 25% of Makapuno fruits. In Vietnam, there have been two Makapuno varieties. One is green and another is yellow. Both of them are different only color of fruit. All other parts are the same. In Philippines, Makapuno have classified to three genotypes (A, B and C). Type A is slightly thicker and softer than normal coconut. Type B has soft solid endosperm filled about 50% of the cavity; and Type C, has a soft solid endosperm almost occupied the cavity, little water. Type C is almost not germination. Germination of Type B is lower than type A. Our results also obtained the same (three types). Presently, market demand of Makapuno is bigger than supply from farms and demand of Makapuno seedlings is also very high. Although Makapuno fruit just is used presently for food, but it is very promising for biofuel in future.

Potential Development of Makapuno coconut in the Mekong Delta of Vietnam

Abstract: In the Mekong delta of Vietnam, there is a coconut variety called Sap coconut or makapuno coconut. Perhaps, this is a mutant coconut type which produced very thick endosperm and viscidity with little or no water. Nowadays, makapuno nuts are used mainly for food processing, very promising for biodiesel in future. The price of makapuno nuts has been rising each year. So the demand of seedlings is also to increase yearly. Based on the demand of makapuno for many different purposes, potential development of makapuno in the Mekong Delta is very high. Studies of the inheritance on makapuno in the Mekong Delta are restricted. However, study results of the inheritance pattern on makapuno bearing trees in the Philippines are very useful for application in the Mekong Delta. Propagation techniques of makapuno could be applied from traditional to modern such as embryo culture. Potential development of makapuno in the Mekong Delta of Vietnam is very promising. Products and by products from makapuno coconut are very diversified and useful and bring back more benefices for farmers. Combination between experiences of farmers and scientific studies will help to develop makapuno plantation obtaining success.

Estimating soil organic carbon sequestration change with applying modified Rothamsted Carbon model to paddy and upland fields in Japan

Abstract: Sustainability of the soil organic carbon (SOC) sequestration of farms producing the cereals which are raw materials of the biomass ethanol is an important issue. We estimated SOC sequestration change of a paddy field soil (Anthrosols) and an upland field soil (Andosols) in Japan with applying the modified RothC models, and suggested appropriate farming management for sustainable agriculture on the basis of SOC sequestration. In the paddy field experimental plots, at forage rice of Tachisugata plots, compost application of 0.5 - 1.2 Mg ha -1 each year was required to maintain SOC content. In contrast, only plant residues in forage rice of Leaf star plots were sufficient to maintain SOC sequestration. In the upland field experimental plots, considering from the prediction, 2 Mg ha -1 compost applications each year at the tillage and chemical fertilizer application plot is sufficient for maintain SOC content. Furthermore, plant residue was vital source of organic matter for chemical fertilizer plot, and SOC content would decrease 14.0 Mg-C ha -1 from 2007 to 2030 if plant residue is carried out from the field. SOC sequestration under diverse assumed management conditions in Japanese fields is predicted. The modeling tool of RothC would be useful to field management for sustainable agriculture, so it is necessary to consider about the field management with using these modeling tools.

Technique of Increasing Brightness Sensation in Lighting Design

Abstract: Brightness perception, which is one of the most important of five senses, has impacted about 70% of all the body's sensory receptors. ( Soonthorn Boonyatikarn, 2004) From interior brightness system survey, it is found that building designed with CIE brightness standard or higher with high capacity of electrical consumption but people still feel dark inside the building. Therefore, this paper objects to analyze interior lighting design factors to increase brightness as well as eye perception and also search for new design implementation to make an effective brightness. Then, it would save electrical consumption of lighting system. The concourse area were selected and surveyed including passenger terminal of Suvarnabhumi Airport. The study started from questionnaire survey for the advantages and disadvantages of architecture interior design which has impacted the brightness perception. Then, brightness data was measured of fore view vision and peripheral vision with statistical questionnaire. Which focused on visual sensation, inspection of void and opening, light beam control and Glare Ratio. The results indicated that existing interior design was decorated with dark color which absorbs a lot of light. The remainder surfaces only allowed day light reflecting as diffuse surface. The fore view and peripheral vision ratio is only 20% of electric lights within the terminal. The interior glass wall decoration effect on brightness glare ratio of both inside and outside the terminal. When passengers walk pass many areas. It caused high level of discomfort glare and make eyes feel uncomfortable. After the development from results constant glare light ratio would be well controlled, the contrast ratio should not exceed 1:3, and use bright painted wall. Furthermore, the lamp could reduce about five times of all serviced electric lights to reduce glare light while passenger pass along. The results illustrate that brightness level can be lower than IEC standard with satisfaction of passenger in the concourse.

Potential application of Brazilian agroforestry in Northern Thailand

Abstract: Promotion of settled farming and conservation of the headwaters forest have been the priorities for Thai government in its efforts to preserve water resources and block soil erosion on the hills. Commercially-oriented agroforestry developed by the Japanese immigrants in the Brazilian Amazon may serve as a model for sustainable farm-income generation and the environmental conservation in the region.