Strength demands of tall wind turbines subject to earthquakes and wind load

Wind and earthquake load have historically been conceived to act independently. However, if we reflect on the fact that major seismic events are usually followed by a number of aftershocks and that wind is constantly flowing at high intensities around wind farms, which induces additional demands of resistance to infrastructure, then the joint probability of middle-to strong earthquakes and low-to mild wind events becomes more relevant. In this paper a generalised approach is used to estimate the ratio between earthquake and wind forces and their effect on infrastructure. Following, a probabilistic analysis is carried out to show that under certain conditions the combination of these natural events can induce additional demands of strength and ductility to wind turbines which could lead to unforeseen damage

An Evaluation of Economic Potential Solar Photovoltaic Farm in Thailand: Case study of Polycrystalline Silicon and Amorphous Silicon Thin Film

Solar energy in Thailand plays an important role to achieve the target of the Alternative Energy Development Plan (AEDP). Enormous investments from investors are expected to occur for support AEDP. Therefore, the objective of this study was to evaluate and compare the economic potential of solar PV farm between polycrystalline silicon (PCSS) and amorphous silicon thin film (ASTF) type. Questionnaires submitted to private solar PV farm for collecting data. As a result, four main investment costs of PSS are identified: (1) photovoltaic module; (2) connection system; (3) inverter, and (4) engineering construction, distributed as 58.09%, 19.66%, 12.96%, and 4.47%, respectively. The financial analysis found that Payback period (PB), Internal Rate of Return (IRR), and Solar Plant capital of ASTF were less than PCSS; however, it returns low income along 25 years than PCSS. It could be suggested that the investment on PCSS is worth than ASTF. Keywords: Economic potential, Solar PV farm, Investment, Financial economic. JEL Classifications: C8, G0, M

Multiple Regression Analysis in the Development of NiFe Cells as Energy Storage Solutions for Intermittent Power Sources Such as Wind or Solar

Multiple regression analysis was used to investigate the effect of bismuth sulphide and iron sulphide as anode additives for NiFe cells. With this in mind, in-house made Fe/FeS/Bi2S3 based electrodes were cycled against commercially available nickel electrodes. A simplex centroid design was used to investigate the combined effects of any of the aforementioned additives on cell performance. The manuscript ends with an initial look at electrolyte systems as a means to further improve the performance of our cells. Finally, our findings support the idea that HS- ions improve the overall performance of NiFe cells

Aqueous batteries as grid scale energy storage solutions

Energy storage technologies are required to make full use of renewable energy sources, and electrochemical cells offer a great deal flexibility in the design of energy systems. For large scale electrochemical storage to be viable, the materials employed and device production methods need to be low cost, devices should be long lasting and safety during operation is of utmost importance. Energy and power densities are of lesser concern. For these reasons, battery chemistries that make use of aqueous electrolytes are favorable candidates where large quantities of energy need to be stored. Herein we describe several different aqueous based battery chemistries and identify some of the research challenges currently hindering their wider adoption. Lead acid batteries represent a mature technology that currently dominates the battery market, however there remain challenges that may prevent their future use at the large scale. Nickel–iron batteries have received a resurgence of interest of late and are known for their long cycle lives and robust nature however improvements in efficiency are needed in order to make them competitive. Other technologies that use aqueous electrolytes and have the potential to be useful in future large-scale applications are briefly introduced. Recent investigations in to the design of nickel–iron cells are reported with it being shown that electrolyte decomposition can be virtually eliminated by employing relatively large concentrations of iron sulfide in the electrode mixture, however this is at the expense of capacity and cycle life

Wind Resource Assessment of the Southernmost Region of Thailand Using Atmospheric and Computational Fluid Dynamics Wind Flow Modeling

This paper presents the wind resource assessment of the southernmost region of Thailand using atmospheric and computational fluid dynamics (CFD) wind flow modeling. The predicted wind data by the Weather Research and Forecasting (WRF) atmospheric modeling, assimilated to a virtual met mast, along with high-resolution topographic and roughness digital data, are then used as the main input for the CFD microscale wind flow modeling and high resolution wind resource mapping at elevations of 80 m, 100 m, 120 m, and 140 m agl. Numerical results are validated using measured wind data. Results show that the potential area where the wind speeds at 120 m agl are above 8.0 m/s is 86 km2, corresponding to a technical power potential in the order of 300 MW. The installation of wind power plants in the areas with the best wind resource could generate 690 GWh/year of electricity, thus avoiding greenhouse gas emissions of 1.2 million tonnes CO2eq/year to the atmosphere. On the other hand, developing power plants with International Electrotechnical Commission (IEC) Class IV wind turbines in areas of lower wind resource, but with easier access, could generate nearly 3000 GWh/yr of energy, with a CO2eq emissions avoidance of 5 million tonnes CO2eq on a yearly basis

Mesoscale/Microscale and CFD Modeling for Wind Resource Assessment: Application to the Andaman Coast of Southern Thailand

Situated in the southern part and on the western coast of Thailand, the Andaman Coast covers the provinces of Ranong, Phangnga, Phuket, Krabi, Trang and Satun. Using a coupled mesoscale atmospheric model and a microscale wind flow model, along with computational fluid dynamics (CFD) modeling, this paper presents a detailed assessment of the wind energy potential for power generation along the Andaman Coast of Thailand. The climatic data are obtained from the Modern Era Retrospective analysis for Research and Applications (MERRA), along with a high-resolution topography database and Land Use Land Cover digital data. The results are compared to the equivalent wind speeds obtained with the Weather Research and Forecasting (WRF) atmospheric model. The results showed that, at 120 m above ground level (agl), the predicted wind speeds from the models proposed were 20% lower for the mesoscale model and 10% lower for the microscale model when compared to the equivalent wind speeds obtained from the WRF model. A CFD wind flow model was then used to investigate 3D wind fields at 120–125 m agl over five potential sites offering promising wind resources. The annual energy productions (AEP) and the capacity factors under three different wake loss models and for five wind turbine generator technologies were optimized for 10-MW wind power plants, as per Thailand’s energy policies. With capacity factors ranging from 20 to 40%, it was found that the AEPs of the best sites were in the range of 18–36 GWh/year, with a total AEP in the vicinity of 135 GWh/year when using a single wind turbine model for the five sites studied. The combined energy productions by these wind power plants, once operational, could avoid GHG emissions of more than 80 ktons of CO2eq/year

High resolution wind atlas for Nakhon Si Thammarat and Songkhla provinces, Thailand

In this work, a high resolution wind atlas for Nakhon Si Thammarat and Songkhla provinces in southern Thailand was developed using combined mesoscale, MC2, and microscale, MsMicro, modeling techniques. The model inputs consist of long-term statistical climate data, i.e. the NCEP/ NCAR database, high resolution topography and land cover data. The 200 m resolution wind resource maps were validated with observed mean wind speeds from 10 met stations located along the coastlines of the territory studied. These comparisons have shown that the wind atlas provides a good representation of the wind resource throughout the territory of Nakhon Si Thammarat and Songkhla provinces, Thailand. The technical power potential and potential annual energy production are then identified. Results from the technical power potential at 80 m above ground level show that a total of 1374 MW of wind farms, generating annually 3.6 TWh of electricity, could be installed; while 407 MW of small wind turbines (50 kW), generating annually 1.0 TWh of electricity, could be installed

Techno-Economic Assessment of a 100 kWp Solar Rooftop PV System for Five Hospitals in Central Southern Thailand

This paper presents a techno-economic assessment of a 100 kWp solar rooftop photovoltaic (PV) system at five hospitals in central southern Thailand.  The system encompasses 100 kWp PV panels, 100 kW grid-tied inverters and balance of system (BOS) under the grid code of the Provincial Electricity Authority (PEA).  The latest PV technology of bifacial mono-crystalline solar panels, inverters and BOS were simulated along with the Meteonorm 7.3 database using the PVsyst simulation toolkit with different tilt angles, orientations, solar radiations and ambient temperature.  The technical aspects of solar rooftop PV power generation systems include the annual energy output and the performance ratio (PR) under IEC standard.  Further, an economic analysis of the model was examined using a cost benefit analysis (CBA) and various assumptions.  Four main financial criteria, i.e., benefit cost ratio (BCR), net present value (NPV), internal rate of return (IRR), and payback period (PBP) were evaluated under three different scenarios: (1) self-consumption scheme, (2) feed-in tariff (FiT) scheme, and (3) private power purchase agreement (PPA) scheme.  Finally, the levelized cost of energy (LCOE) was also calculated.  The results reveal that the Takua Thung hospital is characterized by the maximum average global horizontal irradiation (GHI) and the maximum annual produced energy of 199 kWh/m2 and 164.8 MWh/year, respectively.  The PR calculated for all hospital sites is above 85%. The outcomes of the financial analysis show that the optimum scenarios are PPA and FiT schemes.  The LCOE analysed in this study indicates that the Takua Thung hospital site has the lowest LCOE at 2.47 THB/kWh (0.07 USD/kWh).  This research confirms the potential for hospitals and stakeholders in central southern Thailand for investments in solar rooftop PV system