Journal of Renewable Energy and Environment
Volume:4 Issue: 2, Summer 2017

Abstract Both the continuous and batch transesterification of linseed oil were examined in order to maximize the fatty acid methyl esters (FAME) yield. The continuous process was conducted in a packed bed reactor using calcium oxide as a heterogeneous catalyst. In addition, the impact of two variables, namely the molar ratio of methanol to oil and the flow rate (ml/min), on the FAME yield were studied. Likewise, for the batch process, the reaction was carried out in a CSTR reactor using KOH as a homogeneous catalyst. Moreover, the influence of the molar ratio of methanol to oil and of catalyst concentration (wt. %) on the FAME yield was investigated. For both the batch and continuous process, FAME yield was optimized by using the Design Expert (Ver. 7.0.0) software. The optimum conditions for the continuous method were reported as follows: a molar ratio of methanol to oil of 11.75:1, a flow rate of 1.07 ml/min, and a temperature of 50oC. Under the optimum conditions, a FAME yield of 94.2423% was achieved. For the batch process, a FAME yield of 95.0672% was reached under the optimum conditions of a molar ratio of methanol to oil of 9.12:1, a catalyst concentration of 1.52 wt. %, a temperature of 40oC, an agitation rate of 650 rpm, and a reaction time of 60 minutes.

The energy insecurity, environmental pollution, climate change and even reduced rainfall in some countries are prime examples of consequences of the world’s excessive reliance on fossil fuels. This study suggests that in some southern islands and coastal areas of Iran, two such problems, namely the growing shortage of potable water and air pollution can be addressed by building a wind-powered seawater desalination plant at the locations. To evaluate such project, first the sites that may provide the highest efficiency need to be identified. In this study, 10 ports and 5 islands in southern Iran, which suffer from water shortage but have access to seawater, are identified as preliminary candidate sites for such project. The criteria influencing the suitability of a location are considered to be wind power density, economic feasibility, topographic condition, frequency of natural disasters, population, and the wind farm’s distance from desalination facility. After analyzing and weighting the criteria, the locations are ranked using the ELECTRE III method, and the results are validated using the PROMETHEE method. In conclusion, the results of ranking techniques show that Qeshm Island is the best location for construction of a wind-powered seawater desalination plant.

India seeks to achieve 175 Giga-Watt (GW) of Renewable power by 2022. As of December 2017, out of 333 GW of total installed capacity of electricity, close to 62GW come from renewable sources. Meeting the set targets calls for augmentation of renewable energy based capacities as expeditiously as possible. However, the sick financial health of the distribution companies/utilities, who act as the primary purchasing authorities of such power, is posing as a threat to the success of the renewable industry. This paper highlights that while the cost of procurement of renewable power, to the utilities, has gone down significantly in the recent past; the worsening financial health of utilities remains a key concern. Data is presented to substantiate that the said distribution companies/utilities are saddled by high gaps between Average Cost of Supply (ACS) and Average Revenue Requirement (ARR). Revenues to the power supplying utilities are under-recovered due to the long standing practice of cross- subsidization in the Indian power sector – agricultural and residential consumers of electricity consume power at lower tariffs, than commercial and industrial consumers. A case is therefore suggested for implementing evidence based tariff setting by the utilities. Under the suggested framework, electricity tariffs for different consumer categories can be charged with a premium for green power, based on their willingness to pay for such power. Collected funds, then can be used towards purchase of green power, by the said utilities, and consequently help foster the development of green energy in the country. This study also presents limited empirical evidence, recording the willingness to pay for such premiums, across different categories of “paying” consumers.

Soil microbial fuel cells (SMFCs) are expected as an application to produce sustainable energy. Here, we focused on soil ecosystems, specifically the earthworms which are known to improve soil-fertility by degrading fallen leaves or plant litter. The aim of this study was to investigate the effect of earthworm on power generation of the SMFC. The maximum power density and the internal resistance were compared to the SMFC with and without earthworms. The power density increased by about 800% and the internal resistance decreased by about 90%. The soil structure of each SMFC was different and the clear soil aggregate structure was found in the SMFC with earthworms, which had been made with the passage of soil through the earthworm gut. The results indicated that adding earthworms had a significant effect on the SMFC performance, especially the power and soil structure. It is considered that the soil environments were changed biologically and physicochemically by adding earthworms into SMFC and these changes had a positive influence on SMFC. There is no report of hybrid type SMFC combined with earthworm. This is a very novel approach to use earthworms as enhanced power generation through the SMFC.

In this manuscript, a solar cavity packed with thermoelectric generator modules is investigated numerically. The hot plate of TEG modules make the inner surface of the cube, and the cold plate is outside of the cavity, under natural convection. The TEG modules are electrically in series. The solution algorithm using the equations of heat transfer and generated power of TEG modules is developed via MATLAB and simulated under various non-concentrated irradiation levels. The generated power variation in solar thermoelectric cavity shows that as the solar irradiance rises, the generated power increases at a growing rate. The radiation varies from 700 to 1200 W/m2, and the generated power increases from 0.2 mW to 10 mW for side TEGs and up to 30 mW for bottom side TEGs. Studying the effect of aperture size shows that, although the generated power of fully open cavity is 2.25 times higher than generated power in 5×5 cm2 aperture size cavity but its efficiency is 50% lower than small aperture cavity. Heat transfer analysis of cavity depicts the 91% of heat transferred by conduction in cube surfaces and, only 6% and 3% of input energy are lost by re-radiation and convection through the aperture, respectively.

In Iraq, solar radiation field measurements are available only for very limited locations such as some universities and research centers. This article reviews and compares the measured monthly averaged global solar radiation data for Iraqi provinces and cities available in the literature and studies over the internet especially Google Scholar, Research Gate and IASJ. The selected locations are Baghdad, Mosul, Tikrit, Rutba, Nasiriya, Kirkuk, Haditha, and Najaf. The measured data is compared with the corresponding available satellite data from NASA and Meteonorm software and Root mean square error is calculated to test NASA and Meteonorm performance. The review results show that the maximum GSR in July in Haditha (8.3 kWhr/m2) while the minimum is in Mosul city in December (1.68 kWhr/m2). Baghdad measured monthly mean is about 5.20 kWhr/m2.

The amine regenerator of acid removal unit in South Pars Gas Complex, Assalouyeh, Iran was modeled. This model was fitted to assess the large scale columns and allow application of solar thermal energy for production of low pressure steam. Heat transfer fluids including Therminol oil, sulfur, or salt melt could be applied to yield thermal energy from a solar collector and to store and transfer it to the reboiler of columns. The Angstrom model was adopted here to simulate solar irradiance. Solar irradiance data for the city of Assalouyeh, during the years of 2009-2014, were collected and applied. The results indicated that based on a reboiler duty of around 21.8 MW, a solar collector area of 148,000 m2 was required with a mass of heat transfer and storage medium of 1247255 kg oil, 1787732 kg salt melt and 3803686 kg sulfur, respectively. This model was applied as an analytical tool to explore and describe the following two problems encountered during real plant operation: fouling in the amine heat exchangers and increasing regenerator pressure.