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Bangladesh being a developing country is struggling for the self-sufficiency of electric power for a very long time. In this run renewable energy can play an important role for electricity generation. Bangladesh abuts by Bay of Bengal, as a result the southern areas face around 2∼5 m of tidal head/height rise and fall and as it is in the tropical region it gets an average daylight of 7∼8 hper day. Thus the hydro (tidal) energy and solar energy can be the key points to meet the scarcity of power. This paper discusses a model of possible small hybrid power generation system consisting of a PV generation unit with storage and a micro-hydro generation unit and a diesel generator which can mitigate the rising energy demand at the southern areas of Bangladesh. In this paper the economic viability is discussed along with the technical aspects to set up such system via HOMER analysis. Moreover the system cost was analyzed together with a comparison of other system costs of similar capacity. [ABSTRACT FROM AUTHOR]

Abstract: This paper reviews state of the art maximum power point tracking (MPPT) algorithms for wind energy systems. Due to the instantaneous changing nature of the wind, it is desirable to determine the one optimal generator speed that ensures maximum energy yield. Therefore, it is essential to include a controller that can track the maximum peak regardless of wind speed. The available MPPT algorithms can be classified as either with or without sensors, as well as according to the techniques used to locate the maximum peak. A comparison has been made between the performance of different MPPT algorithms on the basis of various speed responses and ability to achieve the maximum energy yield. Based on simulation results available in the literature, the optimal torque control (OTC) has been found to be the best MPPT method for wind energy systems due to its simplicity. On the other hand, the perturbation and observation (P&O) method is flexible and simple in implementation, but is less efficient and has difficulties determining the optimum step-size. [Copyright &y& Elsevier]

Temperature and solar radiation are two main parameters directly affecting PV (photovoltaic) arrays’ output. Particularly, solar radiation is dependent upon PV arrays’ tilt angles and orientations while PV arrays’ temperatures are related to ambient temperatures. Nevertheless, the effects of ambient temperatures, tilt angles, and orientations on PV arrays’ output for places with equatorial climatic conditions (and abundant sunshine) are scarcely reported. In this paper, the effects of ambient temperatures, tilt angles, and orientations on the total electricity produced by PV arrays and the total NPCs (net present costs) of hybrid PV/diesel systems were studied using HOMER (Hybrid Optimization of Multiple Energy Resources). Three places with different latitudes off the equator (0° 00′ N, 5° 58′ N, and 11° 14′ N) were analyzed and the results showed that increasing ambient temperatures (10–50 °C) and tilt angles (0–90°) resulted in reductions in PV electricity as much as 18% and 55%, respectively. NPC-wise, however, the variations became less pronounced – the NPC differences caused by changes in ambient temperatures and tilt angles became ~6% and ~25%, respectively, under 0% annual real interest rate. As the annual real interest rate increased to 3% and 5%, the NPC differences reduced further. Meanwhile, at 0–30° tilt angles, PV arrays facing different orientations showed differences in NPCs of less than 5%, albeit that the reductions in PV electricity were much higher. Significantly, the implementation of hybrid PV/diesel systems is feasible at places with equatorial climates. [ABSTRACT FROM AUTHOR]

Several factors such as climate change, increment in fuel cost and digital technology era have lead to transformation of conventional grid into smart grid. Existing microgrid can be integrated with smart grid characteristics by various topologies, including cogeneration system where both electricity and thermal energy from single source of fuel can be produced. Cogeneration system has better efficiency, lower costs and able to reduce greenhouse gas emissions compared to singular conventional methods. This paper presents a comprehensive review of cogeneration system, covering the principle operation and types of prime movers available for use in power plant, building and industrial plant. Prime movers such as gas turbine, steam turbine, micro turbine, reciprocate engine and fuel cell are compared in terms of size (kW), efficiency and principal operation. This review also describes the hierarchical control system for cogeneration system; classified into three types, which are local, centralized and decentralized. This study tries to find the most suitable control strategy for certain cogeneration system by referring to the related standards available. A number of cogeneration applications in commercial buildings, including hospital, airport, shopping complex and hotel, are presented to show the effectiveness of the cogeneration system. Overall, this paper presents comparison between each prime mover technology, factors that influence the selection of prime movers, challenges and prospects of cogeneration system. [ABSTRACT FROM AUTHOR]

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 (O&M), operating cost are also analyzed. HOMER software provided by National Renewable Energy Laboratory (NERL) is used as an analyzing tool. This paper also focuses on the operational strategy and sensitivity analysis of the hybrid system for optimal performance. The HOMER optimization results and sensitivity analysis show that the PV/Battery system is economical and environmentally friendly with total net present cost of $ 335,297 and cost of energy of 0.323 $/kWh with no emission. Thus it can be a suitable replacement of diesel based system. The FC based system has higher costs; thus despite of its benefits, it is not suggested as the best system for the situation. [ABSTRACT FROM AUTHOR]

Fuel cell (FC) application in vehicular technology has gained much popularity since the past few years. Typically, fuel Cell Hybrid Electric Vehicle (FCHEV) consists of fuel cell, battery and/or ultracapacitor (UC) as the power sources. The power converter is integrated to the power sources to form the hybrid FC system. This helps to compensate the drawback of individual power sources. Apart from the technical efficiency of power sources itself, the performance of an FCHEV is governed by the efficiency of power electronics and associated controller. In this paper, a state-of-the-art of vehicle classification is reviewed, in which the focus is placed on the deployment of fuel cell, battery, ultracapacitor and flywheel. The configurations used in FCHEV, followed by the updated power converter topologies, are also discussed. The topologies are categorized and discussed according to the power stages and control techniques used in the configurations. Then, multiple stages conversion and single stage topologies are described chronologically. The advantages and disadvantages of each topology, safety standards, current situation and environmental impact of FCHEV are also discussed. In addition, the current development of FCHEV, challenges and future prospects are also elaborated. The rapid growth of FC based research and technology has paved great prospects for FCHEVs in the near future, with the prediction of the competitive cost of hydrogen as compared to gasoline. [ABSTRACT FROM AUTHOR]