Applied Mechanics and Materials Vol. 839

Abstract: This research is aiming at the changing land use from agricultural land to photovoltaic power plant. Geographic information system (GIS) technology was used to indicate the unsuitable areas for five economic crops that are paddy, sugar cane, maize, cassava and para rubber. The assess cost, income, and CO₂ emission of the economic crops and photovoltaic power plant are the major factors for the unsuitable agricultural land deciding that will be changed to build photovoltaic power plant. The results found that the unsuitable areas for the 5 economic crops are 241,142 rai and the average solar irradiance is 17.6 MJ/m².day for this areas which is suitable to build the photovoltaic power plant. The profit/losing of paddy, sugar cane, maize, cassava and para rubber in the suitable areas are-1,193 baht/ton, 33 baht/ton, 85 baht/ton, 259 baht/ton and-9,150 baht/ton, respectively while photovoltaic power plant cost and income are 4.12 baht/kWh and 5.65 baht/kWh respectively. CO₂ emission of paddy, sugar cane, maize, cassava, para rubber and photovoltaic power plant are 2,315 kgCO₂eq/ton_paddy, 37.15 kgCO₂eq/ton, 256.12 kgCO₂eq/ton, 29.07 kgCO₂eq/ton, 153 kgCO₂eq/ton and-0.5743 kgCO₂eq/kWh, respectively. From these results, land use changing from economic crops planting in unsuitable areas to build photovoltaic power plant is appropriate and worth in the environmental and the economic aspect.

Abstract: Electricity generation from solar energy by using PV cells is drastically increased due to global warming concern, greenhouse effect, and quality of living standards. However, PV generation may offer variable and unpredictable energy output due to intermittent nature of solar irradiance and hence, integration of PV into grid may provide some drawback effect to the power system. The aim of this paper is to investigate the impact of grid connected PV system on the power quality of distribution network. The power quality analysis is based on real measurements of 10 kWp, Energy Park SERT, School of Renewable Energy, Naresuan University, Thailand. Parameters such as active and reactive power, voltage, current, power factor, THDv, THDi, individual harmonic voltage and harmonic current are observed for the investigation of the interaction between SERT PV system and distribution network’s power quality. According to the measured data, PV system operation is negligible in terms of voltage distortion, voltage magnitude and frequency variation. Therefore, it can be noticed that 10 kWp SERT PV system does not effect on the distribution system power quality due to low PV penetration level.

Abstract: In this research paper, an illustration for system size optimization for a stand-alone PV – diesel hybrid system is obtained. The requirement is to obtain an optimal size that can meet energy demand at an optimized cost for a given lifetime period of the project, this will be achieved using HOMER software to further improve the system parameters like performance ratio, renewable energy fraction, MATLAB will be used. This research study will be done basing on a system currently installed at the School of Renewable Energy, Naresuan University (SERT), this system has a capacity of 120 kW, and it is a hybrid system with PV array, Diesel generator and battery storage system. The cost parameters that will be addressed are; - Net present cost (NPC), Cost of Energy (COE), Capital cost (CC). The initial size of the hybrid system is PV-120kW, Diesel generator -100kW and battery storage of 200kWh after modelling and simulation with HOMER software using special models to show the predicted performance of the final outcome, the optimal size created has a PV size of 100kW, diesel generator with a size of 100kW and battery storage of 100kWh and compared to the initial system COE od 1.01$/kWh, the optimal size has a COE of 0.934$/kWh.

Abstract: Antimony sulfide (Sb₂S₃) nanostructure was synthesized using a 600 W microwave irradiation technique. The precursors including Sb(CH₃CO₂)₃ and Na₂S₂O₃.5H₂O were dissolved into 50 mL ethylene glycol (EG) solution with containing 0 and 1 g of hydroxyethyl cellulose (HEC). Phase, morphology and optical properties of the as-synthesized products were determined by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-visible spectroscopy and photoluminescence (PL). Energy band gap of Sb₂S₃ nanostructure exhibits the value of 1.90 and 2.06 eV for synthesizing condition with and without HEC containing, respectively.

Abstract: This paper presents the technical and economic assessment of a 10 MW wind farm at Pakphanang district in Nakhon Si Thammarat province, southern Thailand. The microscale wind resource map within 10 km is developed based on 3 years recorded wind data at 120 m above ground level (agl) (2012-2014) along with computational fluid dynamic (CFD) wind flow modeling with resolution of 90 m. The 5 x 2.0 MW and 4 x 2.5 MW modeled wind farms are positioned along the shoreline with a position criteria of 5 times the rotor diameter between the turbines. The net annual energy production (AEP) and capacity factor (CF) with wake losses are analyzed. The economic analysis is done based on the current project cost and financial incentive (Adder). Results show that the annual mean speed at 120 m agl is 5.2 m/s. The net AEP and CF are 36.60 GWh/year and 41.78%, respectively with wake loss of 0.40%. Under project cost of 75 million THB/MW and 70% debt ratio and Thailand Board of Investment (BOI) tax exemption promotion, the benefit cost ratio is 1.04, the net present value is 65.96 million THB, the financial internal rate of return is 17.70% and the payback period is 4 years. Finally, a 10 MW wind power project could avoid greenhouse gas emission of 19,764 tons CO₂eq per year.Keywords: Wind Energy, Wind Farm, Capacity Factor, Wind Flow Modeling, Project Analysis

Abstract: Energy and food security are two key national policies and agenda of Thailand. The Department of Alternative Energy Development and Efficiency (DEDE), Ministry of Energy has modified a 15-year (2008-2021) Alternative Energy Development Plan (AEDP). According to the modified AEDP, the share of renewable and alternative energy consumption should increase to 25% by 2021. The latest policy aims to promote the biodiesel consumption and production by 5.97 million liters/day within 2021, up from its previous plan of 4.50 million liters/day while nowadays production capacity is 1.62 million liters/day. The current and anticipated production of biodiesel require raw materials, notably crude palm oil (CPO) from oil palm plantations. This paper presents a feasibility study, with respect to the AEDP plan, for biodiesel production by using domestic fresh fruit oil palm as a raw material. Demand and supply are analyzed based on statistical modeling and forecasting techniques, as well as GIS spatial analysis. The results show that the domestic CPO consumption for cooking palm oil will be 1.02 million tons/year, while biodiesel production will be 1.67 million tons/year in 2021. This corresponds to an oil palm plantation area of 11,152 km² in 2021. Based on GIS spatial analysis along with land-use database and other relevant databases, it was found that the suitable area for palm oil plantation in Thailand is 14,639 km², which is sufficient for domestic demand and consumption. The suitable area consists of 9,664 km² for quite suitable and 4,975 km² for medium suitable. However, the government should provide the guidelines, along with pro-active and supportive policies for worst case scenarios, e.g. drought and flood leading to the insufficient raw material, in order to reduce the negative impacts of biodiesel production for domestic demand and consumption.

Abstract: This paper focuses on to evaluate technical performance of PV roof top system. This system totally consists of 168 polycrystalline modules in which 14 are connected in series and 12 are connected in parallel. The total capacity of the system is 50 kWp, in which each module has the rated power capacity of 305 Watt. This system is connected to three 20kW inverters and which intern is connected to grid. Tilt angle and orientation is obtained by MATLAB 7.10 and PVsyst software for each 15⁰ change in tilt angle, the variation in solar irradiance absorbed by the PV modules, variation in energy produced by the modules and the variation in the final yield are observed. MATLAB software is also used to find the curve fitting by using surface fitting tool. The result showed that at 15⁰ tilt and 45⁰ azimuth angles, the maximum yield and effective energy were obtained as 4.65 h/day and 1394 kWh/kWp/year respectively.

Abstract: Liquid organic hydrogen carriers (LOHC) are a promising form to store hydrogen. However, the process of dehydrogenation has to be demonstrated for applications with proton exchange membrane (PEM) fuel cells which require very pure hydrogen. Here we document the measured degradation effects due to CO contamination on a PEM fuel cell that is supplied with hydrogen from a LOHC and we want to use later in a maritime application.

Abstract: The high level of renewable electricity generation is resulting in transformation of conventional grid into Smart Grid. Due to variable electricity generation the load demand has become critical and challenging issue in electricity market. In this study, the end-use load modeling based on probability distribution has been carried out in School of Renewable Energy Technology (SERT) Naresuan University Phitsanalok Thailand. For the data of electricity usage in office at SERT the most suitable model i.e., Weibull distribution have been emulated. The shape and scale parameters have been estimated along with Kolmogorov-Smirnov goodness of fit test.

Abstract: Effects of shading and blocking of solar radiation intensity through Fresnel lens onto solar cell were investigated in this work. Fresnel lens was made of polyvinyl chloride to concentrate the solar radiation onto the polycrystalline silicon solar cell with the 0.767 m x 0.670 m in size and no cooling under the solar panels. The temperature and efficiency comparisons between solar module with and without Fresnel lens were observed. The performance of the two modules overtime is assessed by monitoring the characteristic I-V and P-V curves. The maximum efficiency of the solar panels with Fresnel lens and without Fresnel lens in each hour was approximately 5-6.7% and 8.8-11.5%, respectively. This lower efficiency of PV module with Fresnel lens was a result of unsuitable distance of Fresnel lens that operated with the PV module.