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Growing environmental concerns due to emission of greenhouse gas from the use of nonrenewable resources can be reduced with the aid of renewable resources, which are considered as an alternative fuel in the absence of fossil fuel in the future. Biomass, one of the renewable resources, is supposed to play an important role in energy sectors because it is the second cheapest energy source among the renewable resources. Apart from generating electricity by using the current biomass technology, such as combustion, gasification, or pyrolysis, a combination of binary and gasification can be one of the effective ways to harvest energy from biomass and to secure the energy production. In term of biomass, Malaysia is blessed with a plenty of renewable energy resources including solar, biomass, and hydro. Hence, a combined binary and biomass power generation can be a promising source of energy generation. In this work, a techno-economic feasibility study on a binary and gasifier-based power generation system from biomass and municipal waste is conducted. The study is conducted to determine the suitability of the system development in Malaysia based on the current resources available. From the results obtained, it is found that the estimated amount of electricity generated from palm empty fruit bunch and municipal waste is 369.65 GWh/yr and 21 262.327 84 GWh/yr, respectively, using combined binary and gasifier-based power generation. Thus, a combined binary and gasifier-based power generation from biomass and biowaste is feasible to be developed in Malaysia. [ABSTRACT FROM AUTHOR]

• Analysis of the lines shielding failure and back flashover performance. • Investigating the impact of each flashover parameter by multivariate analysis. • Simulated fault waveforms exhibit similar pattern with recorded field waveforms. • The average peak voltage difference between the simulated and actual data is 6 %. • Obtained waveforms are useful for designing lightning fault classification system. Lightning overvoltage causes outages of transmission lines (TLs) in tropical countries. Identifying and analyzing the key factors responsible for tripping the lines can improve the performance of the lines. In this work, the flashover patterns due to direct lightning strikes on 275 kV double circuit TLs and towers in Malaysia was evaluated with Electromagnetic Transient Program (EMTP-RV). Three parameters that include lightning current magnitude, power frequency angle and tower footing resistance were analyzed on the line performance during direct lightning strikes. The simulated results found that two key parameters, lightning current at 270 kA and footing resistance at 50 Ω, reveal the highest impact on the insulator flashover. This finding was also verified from multivariate analysis results which is rarely found in the previous works in this field. As a key contribution in this work and in validation to the model, the simulated fault waveform patterns and voltage magnitudes were compared with the actual site data obtained from six different locations in Peninsular Malaysia. The analyzed results show a similar waveform pattern with an overall average voltage magnitude difference of 6.0 % before and after fault. The model is useful to electric utilities for analyzing transient performance of TLs. [Display omitted] [ABSTRACT FROM AUTHOR]

• Analysis of NGLA, EGLA, and MCIA performance on mitigating double circuit tripping. • Installing four arresters per tower is the most optimal and universal solution. • All arresters are operating below manufacturers' maximum discharge energy level. • MCIA discharges 54% and 44% less energy than NGLA and EGLA respectively. • The most suitable arrester was selected based on the proposed protocol. Direct lightning strikes on overhead lines and towers causes power system outages. Optimal surge arrester placement is a practical and economical protection technique. From research trends, three types of transmission line arresters are in practice: Non-Gapped Line Arrester (NGLA), Externally Gapped Line Arrester (EGLA) and Multi Chamber Insulator Arrester (MCIA). This study proposed a simplified guide for selecting the most suitable line arrester considering the placement configurations, double circuit outage prevention and energy capabilities. Electromagnetic Transient Program was implemented to analyze back flashover performance of a typical 275 kV double circuit transmission line in Malaysia. Critical flashover parameters considered are lightning current magnitude, tower footing resistance, and power frequency angle. Analyzed results from the three arresters found that installing four arresters, two per circuit, at the lower and upper phases respectively, is the most optimal and universal double outage mitigation technique. Energy comparison reveals that MCIA discharges 54% and 44% less energy than NGLA and EGLA respectively. Also, from 132 kV system results, MCIA discharges 74% and 22% lesser energy respectively. From further validation of the simulation model, NGLA discharged 23.8% more energy than EGLA from experimental results. The proposed guide is applicable to double circuit lines below 275 kV. [ABSTRACT FROM AUTHOR]

For binary cycle power plants, the energy of solar may be utilized as a heating source. Malaysia has a tropical climate, which receives 4500 kWh/m2 of solar irradiation on a daily basis and roughly 12 h of sunshine every day. Thus, the potential of binary power cycle plants in Malaysia by utilizing the energy of solar as a source of heat is very promising. However, to date, no feasibility study on binary power cycle generation by using the energy of solar as a source of heat in Malaysia has been conducted. Therefore, in this work, a techno-economic analysis on the proposed binary power cycle generation in Malaysia is conducted using commercially available software, HOMER and MATLAB Simulink. The analysis is conducted to assess the proposed binary power generation implementation in Malaysia. Particle Swarm Optimization (PSO), Artificial Bee Colony (ABC) and Teaching Learning Based Optimization (TLBO) are three separate metaheuristic algorithms that are exploited so as to determine the optimum cost of economic of the project. From the results obtained in this work, TLBO gives the most optimized economic cost compared to PSO and ABC. Also, it is found that binary power cycle generation by using energy of solar as a source of heat is feasible in Malaysia. [ABSTRACT FROM AUTHOR]

Highlights • Several surge arrester configurations on a 132 kV double circuit transmission line were modelled. • The energy discharged by lightning strokes during back flashover phenomena was investigated. • The most effective protection design were determined based on the actual tripping pattern. • Double circuit line tripping can be completely eliminated by installing arresters at each phase. • The chosen arrester configuration provides sufficient protection to transmission lines. Abstract Surge arrester has been proven to be the most effective application to provide optimum lightning protection for the transmission line. Thus, many works on optimizing lightning protection for transmission line have been conducted since the past. However, works on minimizing double circuit outages and surge arrester physical properties during transient overvoltages are less likely to be found. Therefore, in this work, several surge arrester configurations installed on a 132 kV double circuit transmission line were modelled using EMTP-RV to investigate their capability to withstand current and energy discharged by lightning strokes during back flashover phenomena. These configurations were then compared to determine the most effective protection design based on the actual tripping pattern recorded by the lightning detection system (LDS) in Malaysia. The selection was made by considering arresters' discharge energy due to variation in tower footing resistance, current magnitude, power frequency voltage, lightning tail time and front time, number of towers and span length. It was found that double circuit transmission line tripping can be completely eliminated by installing surge arresters at each phase conductor of one circuit. The selected arresters configuration provides sufficient lightning protection to the transmission line and complies with the discharge energy capability requirement specified by the utility company in Malaysia, of 5.1 kJ/kV for maximum continuous operating voltage (MCOV). [ABSTRACT FROM AUTHOR]