Current Alternative Energy - Current Issue

Background: As an important developing renewable and sustainable energy source, biodiesel has been consideredaround the world due to its excellent environmental impacts. This paper discussed the advantages and disadvantages of four different biodiesel production methods.

Method: Compared with the homogeneous catalytic and supercritical methods, the heterogeneous catalytic and biocatalyst methods would be better choice in the future under the consideration of environmentalfriendlinessand ease of operation as well as high reaction activity for the catalytic conversion reaction.

Results: This paper also reviewed the biodiesel upgrading technologies for promotingits commercial industrial applications. In addition to be directly used as additives for light fuels and solvents of chemical products, the free of oxygen biofuels, alkanes, and epoxy compounds could be further produced from biodiesel via hydrotreating process, electrochemical synthesis and epoxidation technology, respectively.

Conclusion: All these upgrading and refining technologies not only could resolve the poor low-temperature properties of biodiesel, but also deeply promote the biodiesel commercial industrial application and its sustainable development.

Background: The vast percentage of people of the world; particularly in the developing countries; are living mostly in the decentralized, rural and remote areas which are geographically secluded from the national grid connection. Power distribution and continuous fuel transportation needed to produce the electrical energy for these areas pose a great challenge. Using renewable energy resources in off grid hybrid energy might be a promising solution.

Methods: Moreover, high cost of renewable energy systems has led to its slow implementation in many countries. Hence, it is vital to select an appropriate system size in order to reduce the cost as well as to make the use of available resources more efficient. An off-grid hybrid energy system has been designed as well as simulated to support a small community considering an average load demand of 80 kWh/d with a peak load of 8.1 kW. The simulation and optimization of operations of the system have been done by HOMER software using the real time field data of solar radiation, wind speed and biomass of that particular area. The simulation ensures that the system is economically and environmentally feasible with respect to net present cost (NPC) and CO2 emission limitations.

Results: The result shows that NPC and CO2 emission can be reduced about 29.65%; equivalent to 16 tons per year as compared to conventional power plants. The NPC of the optimized system has been found to be about USD 160,626.00, having the per unit Cost of Energy (COE) of USD 0.431/kWh.

Conclusion: The analyzed hybrid energy system might be applicable for other regions of the world where there are similar climatic conditions.

Background: To cope up with the rapid growth of cities, automation, computation, at the same time, the global pollution level for increasing combustion of fossil fuels to energy, the need of hour is to find an alternative energy resource from renewable fuels.

Methods: Glucose and alcohol based biofuels were produced from pretreated mango tree wood floor by enzymatic saccharification and fermentation. It was found that pretreatment of the biomass has a strong effect on the quantity of the fuel produced. The fuel converted by enzymatic saccharification was a glucose based fuel, while that by fermentation was an alcohol based fuel.

Results: The quantity of fuel produced was estimated as the amount oxygen required for its full combustion (COD mg/l). The COD was higher for the alcoholic based fuel than the former one. Both the fuels could be converted to pure electrical energy by electrochemical oxidation on a electrolytically developed MnO2. The MnO2 anode was produced by electrolytic decomposition from MnSO4 solution.

Conclusion: This inexpensive electrode outperformed the well known Pt electrocatalytic material and delivered a current density in the range of 5-12 mA/cm² .

Background: A distribution system which supplies clean power to the users is the requirement of the modern time. Solar PVs are integrated with the power electronics interface in the conventional system to cater the load demand.

Methods:This arrangement injects harmonics in the system. Furthermore, the diverse nature of the consumer load injects potential harmonics in the system. The harmonic polluted such system produces the harmful effect on the connected equipment. To minimize the impact of harmonics and improve the distribution grid performance, passive filters are obvious choice due to their portable and low cost solution. This paper presents the planning and performance evaluation of C-type passive filters for a solar PV integrated distribution system. The goal of this paper is to plan and evaluate the performance of passive filter from various aspects to check its suitability for solar PV integrated distribution system.

Results: This paper presents the results on the effectiveness of C-type filter for minimizing harmonic distortions and resonance in distribution grid.

Conclusion: Our findings show that the C-type filter effectively mitigate the potential harmonics and alleviate the harmonic resonance problem, thereby improving the power quality and protective system performance.

Background: This research paper mainly deals with a comprehensive thermodynamic modeling and thermoeconomic analysis and optimization of a CCHP system. This integrated CCHP system consists of a topping cycle, an internal combustion engine (ICE), to produce electricity and a bottoming cycle to utilize the wasted heat of exhaust gases by means of an organic Rankine cycle (ORC), an ejector refrigeration cycle (ERC), and a domestic hot water (DHW).

Methods: A comprehensive thermodynamic assessment is carried out to determine the effect of major parameters on the performance of the system in terms of exergy efficiency and total cost rate. The total cost rate includes the purchase equipment cost, the fuel cost, and the environmental impact damage cost. Finally, a multi objective optimization is applied to maximize the exergy efficiency and to minimize the total cost rate of the system while satisfying some practical constraints.

Results: As a result, the Pareto frontier is obtained from our developed multi-objective optimization code for the decision and energy policy makers in order to have better insights to design a system for sustainable future.

Background: The performance of a Dye-Sensitized Solar Module (DSSM) has been investigated under different outdoor air mass (AM), irradiance intensity and temperature conditions in Wajir, Kitui, Vihiga and Kajiado Counties in Kenya.

Methods: The performance was thereafter compared with that of Amorphous Silicon (a-Si) devices undertaken under similar weather conditions in Nigeria. The DSSM’s good response to short wavelength radiation made it perform better at increased AM values than what has been reported of a-Si PV modules.

Results: Studies on a-Si showed that their performance favors low AM conditions. The DSSM generally performed better than what is reported of a-Si, based on irradiance and temperature dependence. Nonetheless, a-Si devices performed better at higher irradiance intensities. These results show that Dye-Sensitized and a-Si technologies complement each others’ performance when subjected to the outdoor field AM, irradiance and temperature conditions.

Conclusion: These findings can be applied in PV sizing, especially for application in Building Integrated Photovoltaics (BIPV) in the tropics.

Background: As far as urban transportation is significantly responsible for the current envi-ronmental issues, significant effort is put on designing and implementing efficient electric vehicles. Solar power seems to be an important option in that direction, thus we have developed a zero-emissions vehicle for urban use, that makes use of photovoltaic panels to charge the battery bank. More precisely, a two-seated four-wheels buggy-type vehicle has been designed, developed and tested on the road,, which has low dimensions and is of a relatively high area available.

Methods: Two 48 VDC /1.5 kW hub motors were positioned at the rear wheels, where four 12V/100Ah batteries connected in series were used to supply the motors. Flexible photovoltaic panels of overall 0.9 Kw peak power have also been used to charge the battery bank. The vehicle was integrated with electric brakes (front) and hydraulic disk brakes (rear). In order to test the vehicles, tree different patterns for typical users have been selected: (a) unstoppable use, (b) regular urban use, and (c) normal employee transportation.

Results: In all cases and independently of the solar radiation intense, the configurations presented good performance, being able to cover normal urban transportation for any pattern of use considered.

Conclusion: This work is actually another evidence that solar cars for urban use are feasible, especially for locations with favorable solar potential.