Nahidul Hoque Samrat

Bio: Nahidul Hoque Samrat is an academic researcher from University of Malaya. The author has contributed to research in topics: Renewable energy & Intermittent energy source. The author has an hindex of 5, co-authored 10 publications receiving 125 citations.

Modeling, control, and simulation of battery storage photovoltaic-wave energy hybrid renewable power generation systems for island electrification in Malaysia.

Abstract: Today, the whole world faces a great challenge to overcome the environmental problems related to global energy production. Most of the islands throughout the world depend on fossil fuel importation with respect to energy production. Recent development and research on green energy sources can assure sustainable power supply for the islands. But unpredictable nature and high dependency on weather conditions are the main limitations of renewable energy sources. To overcome this drawback, different renewable sources and converters need to be integrated with each other. This paper proposes a standalone hybrid photovoltaic- (PV-) wave energy conversion system with energy storage. In the proposed hybrid system, control of the bidirectional buck-boost DC-DC converter (BBDC) is used to maintain the constant dc-link voltage. It also accumulates the excess hybrid power in the battery bank and supplies this power to the system load during the shortage of hybrid power. A three-phase complex vector control scheme voltage source inverter (VSI) is used to control the load side voltage in terms of the frequency and voltage amplitude. Based on the simulation results obtained from Matlab/Simulink, it has been found that the overall hybrid framework is capable of working under the variable weather and load conditions.

Technical Study of a Standalone Photovoltaic–Wind Energy Based Hybrid Power Supply Systems for Island Electrification in Malaysia

Abstract: Energy is one of the most important factors in the socioeconomic development of a country. In a developing country like Malaysia, the development of islands is mostly related to the availability of electric power. Power generated by renewable energy sources has recently become one of the most promising solutions for the electrification of islands and remote rural areas. But high dependency on weather conditions and the unpredictable nature of these renewable energy sources are the main drawbacks. To overcome this weakness, different green energy sources and power electronic converters need to be integrated with each other. This study presents a battery storage hybrid standalone photovoltaic-wind energy power supply system. In the proposed standalone hybrid system, a DC-DC buck-boost bidirectional converter controller is used to accumulates the surplus hybrid power in the battery bank and supplies this power to the load during the hybrid power shortage by maintaining the constant dc-link voltage. A three-phase voltage source inverter complex vector control scheme is used to control the load side voltage in terms of the voltage amplitude and frequency. Based on the simulation results obtained from MATLAB/Simulink, it has been found that the overall hybrid framework is capable of working under variable weather and load conditions.

Prospect of wave energy in Malaysia

Abstract: In developing country like Malaysia, the demand for electricity is expected to rise with increasing urbanization and rapid industrialization. Currently energy production is mainly dependent on fossil fuel but in the near future fossil fuels will not be sustainable because of the depletion of existing reserves and their impact on the environment. Wave energy is an environmentally friendly and fastest growing renewable energy source for a sustainable electrical power generation of the future. Unlike others renewable energy resources, wave energy can produce electric power all over the year. As Malaysia has a total coastline of 4,675 kilometers so there is a great potential for utilization of wave energy in Malaysia especially along the coast and the islands. This paper presents a feasibility study of wave energy at different locations in Malaysia including the estimation of the total power available from the seas surroundings Malaysia. Furthermore, the analysis of investment, operation and maintenance cost for a wave farm is also presented.

A comprehensive study on green technologies used in the vehicle

Abstract: To ensure the safety of environment a major challenge to the vehicle manufacturer is the emission rate of vehicle. Emission of environment polluting particles especially CO 2 from conventional vehicles is a direct threat to the environment. As global vehicle market are expanding day by day so this high rate of emission is already a nightmare to the environment specialist. That's why some of green technologies are introduced in the vehicle by which energy reuse can be happened in the vehicle. Which can impressively reduce the emission of polluting particles from the vehicle. The impressive add-ons among this technologies are fuel cell which can reduce the rate of environment pollution near zero level. Research are going on full swing on the other green technologies like the addition solar cell in the vehicle. Due to some limitations this awaited technology is yet to reach the remote people. Recovering exhaust heat and vibration energy can be a good source of energy in the vehicle. In this paper technologies invented in various time, used in the vehicle for a greener world like regenerative breaking system, fuel cell, energy harvesting from vibration, recovering exhaust heat and the use of photovoltaic panel in vehicle are briefly discussed. Beside this the business perspective of this technologies and cost of producing power from them are discussed.

Multi-directional solar tracker using low cost photo sensor matrix

Abstract: A solar tracking system is designed for the orientation of different solar energy receivers, photovoltaic arrays or thermal receivers to maximize the operation of solar energy conversion This paper deals with the design and implementation of a multi-directional solar tracking system dedicated to use with PV panels The proposed solar tracking device ensures the maximization of the conversion of solar energy into electricity by properly orienting the PV panel in accordance with the real position of the sun The dual axis solar tracker moves only in vertical direction with Y and Z-axis movement It cannot move in horizontal direction with X-axis movement Our proposed model can move in vertical position with Y-axis movement and in horizontal position with X-axis movement and also move at a point in Z-axis making combination of X and Y-axis movement The gain of output power with the Multi-directional tracking system is higher when compared with a dual axis tracker The performance of the proposed solar tracker was experimentally analyzed

Wave energy device and breakwater integration: A review

Abstract: One of the most abundant energy sources exists in this world is the ocean wave energy. By far, it has shown to be the most clean, renewable, predicted energy and has raised the potential to compete with the current use of non-renewable energy sources. Recent research conducted on wave energy invention has opened a new dimension to slowly reduce the dependency on fossil fuel by introducing new technology on the renewable world but relatively lacking in economical aspect. This review brings the latest status on integration of wave energy device with other marine facilities, which is the breakwater structure that may possibly aid to cost sharing. Most researches done on this field highlighted countries experiencing rough sea condition and focused less on countries with medium wave condition as faced by the Asian continent. The potential for energy extraction and wave dissipation for medium wave condition will be discussed in this review by considering several aspects including reliability, effectiveness and performance. Finally, this review shows that the integration opens up a new dimension to acknowledge the technology harnessing ocean wave, especially for the Asian countries experiencing medium wave condition.

Feasibility analysis of hybrid photovoltaic/battery/fuel cell energy system for an indigenous residence in East Malaysia

Abstract: Costly and eco-destructive diesel based systems are usually used for electrifying rural areas in Malaysia. Fuel transportation is another obstacle in this regard. Moreover, unpredictable fluctuation of fuel price makes the system cost unstable. The diesel based systems can be replaced with renewable energy (RE) based systems. Thus, a feasibility analysis is necessary to assess the potentiality of RE resources. This paper analyzes the potentiality of renewable energy in Sarawak, East Malaysia. The wind speed is insufficient, but solar energy is abundant at the location. Hence, the feasibility of photovoltaic (PV), Battery and Fuel Cell (FC) based systems are investigated for the load of a village longhouse comprising 50 families located in Kapit, Sarawak. Both systems, including FC (PV/Battery/FC) and excluding FC (PV/Battery) are analyzed and compared with conventional diesel based system. The analysis focuses on net present cost (NPC) and cost of energy (COE). Other cost parameters such as installation cost, operation and maintenance cost (OM thus despite of its benefits, it is not suggested as the best system for the situation.

Antifungals discovery: an insight into new strategies to combat antifungal resistance

Abstract: Undeniably, new antifungal treatments are necessary against pathogenic fungi. Fungal infections have significantly increased in recent decades, being highlighted as important causes of morbidity and mortality, particularly in immunocompromised patients. Five main antifungal classes are used: (i) azoles, (ii) echinocandins, (iii) polyenes, (iv) allylamines and (v) pyrimidine analogues. Moreover, the treatment of mycoses has several limitations, such as undesirable side effects, narrow activity spectrum, a small number of targets and fungal resistance, which are still of major concern in clinical practice. The discovery of new antifungals is mostly achieved by the screening of natural or synthetic/semisynthetic chemical compounds. The most recent discoveries in drug resistance mechanism and their avoidance were explored in a review, focusing on different antifungal targets, as well as new agents or strategies, such as combination therapy, that could improve antifungal therapy. Significance and Impact of the Study The failure to respond to antifungal therapy is complex and is associated with microbiological resistance and increased expression of virulence in fungal pathogens. Thus, this review offers an overview of current challenges in the treatment of fungal infections associated with increased antifungal drug resistance and the formation of biofilms in these opportunistic pathogens. Furthermore, the most recent and potential strategies to combat fungal pathogens are explored here, focusing on new agents as well as innovative approaches, such as combination therapy between antifungal drugs or with natural compounds.

Control, power and electrical components in wave energy conversion systems: A review of the technologies

Abstract: The purpose of this paper is to introduce the status of wave energy conversion (WEC) technologies from a different perspective. Past studies based on WEC systems are summarized and classified in terms of WEC system components to clearly reveal the performance, efficiency and development of WEC technologies over the last two decades. It has been proved that the individual components of a WEC system, such as types of wave energy converter and generator motion, control methods and power electronic converter, have a close relationship with each other and that no single component can be optimized without considering the others. It can be helpful to divide into descriptive parts to provide a better understanding of the development process for WEC technologies so that studies based on WEC technologies are discussed by regarding types of wave energy converters, generators, control methods, controller applied sides, waves, power electronic converters and validations and publication year in this paper.