This paper proposes the bidirectional resonant converter with duty cycle voltage control using for CCTV with solar energy. The converter designed at 20 KHz for 20 W with 92.85 % of efficiency is operated at zero voltage switch mode for reducing the losses of converter. The modes of operation divide in two modes for operating bidirectional current. The first part is buck mode which has 5 volt at the output voltage and second is boost mode which has 8 volt at the output voltage. The two operation modes of converter will be discussed in this paper.

This research is studied the design and contract the electronic generator from Solar cell integrated with electrical at home in the rural area. The design is combined between solar cell and electrical at home. The mutation from solar cell to electric power is the clean and green energy when it is compared with normal processes to generate the electric power. Additionally it’s also less impacts to environment and sustainable. In the normal architectural model of solar cell generator the engineer will design the power storage at its battery for one day using with condition of the solar cells need to receive the sun light in the whole day. If some days the cell cannot get enough sunlight when it’s bad weather the battery also cannot supply power as in its usual. With this new innovative energy supply integration between solar cell and electrical at home it benefits to the energy consumers to get the energy for whole day continually and also reduce the pollution from the normal process electric generation.

This research aims to study the effect of drying temperature on the changes in the moisture content of charcoal briquettes undergoing drying of solar energy and far-infrared radiation (Solar+FIR) and far-infrared radiation (FIR). The electricity consumption and the specific energy consumption were also investigated. The coconut shell charcoal briquettes with the initial moisture content of about 41-43% MW were dried at 55 60 and 65oC until the final moisture content of 8% MW was obtained. Based on the experimental results it was found that the drying temperatures and the drying methods had effects on the changes in the moisture content of charcoal briquettes. Drying at high temperature could reduce the moisture content of charcoal briquettes faster than that at low temperature. Drying using FIR could reduce the moisture content of charcoal briquettes faster than that using Solar+FIR. Moreover the electricity consumption and the specific energy consumption decreased with an increase in the drying temperature. Drying using Solar+FIR had lower electricity consumption but had higher specific energy consumption than drying using FIR. In this study the charcoal briquettes had the average heating value of about 6667.05 cal/g.

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The amount of dissolved oxygen (DO) in aquaculture ponds is considered to be one of the most important aspects for the survival of fishes. The water in aquaculture ponds is stratified into distinct layers with different DO caused by differences in temperature. This temperature difference occurs when the surface layer of water heated by the sun becomes hotter than the lower water layer. Since the top layer is in contact with the air it contains the most DO. On the other hand the deepest layer is isolated from the air it contains the lowest amount of DO. This study proposed an aeration system called a Solar Circulating-Water Aeration System (SCWAS). The SCWAS uses solar thermal energy to create a natural water circulation. In other words it provides an upward current of water from the bottom to the pond surface and a downward current from the surface to the bottom. This circulation creates the movement of surface water and then increases the DO content of the surface water. This water circulation moves highly oxygenated surface water to the bottom layer forcing low oxygen water from the bottom up to the surface where it can absorb oxygen. To evaluate this design concept the numerical simulations of the system were conducted using ANSYS Fluent software. According to the simulation results the SCWAS can provide the natural water circulation. It was found that a flow rate of 2.24 L/s is obtained when the ratio between the draft tube inlet (r) the draft tube outlet (R) the base (L) is 1: 2: 3. In addition an SCWAS prototype was built and installed in a tilapia aquaculture system. A calibrated measuring system was installed to investigate the prototype performance. The experimental results indicate that the average DO values at the water surface and at the bottom of the pond increased by 1.45 and 1.40 times respectively compared with those of a pond without SCWAS. Economic analysis shows that the payback period of SCWAS is 4.58 years and its investment cost is 17.49% less than that of the paddle-wheel aerator.