New Renewable Energy Sources Research Articles

Primary Control Effort Under Fluctuating Power Generation in Realistic High-Voltage Power Networks

Many recent works in control of electric power systems have investigated their synchronization through global performance metrics under external disturbances. The approach is motivated by fundamental changes in the operation of power grids, in particular by the substitution of conventional power plants with new renewable sources of electrical energy. This substitution will simultaneously increase fluctuations in power generation and reduce the available mechanical inertia. It is crucial to understand how strongly these two evolutions will impact grid stability. With very few, mostly numerical exceptions, earlier works on performance metrics had to rely on unrealistic assumptions of grid homogeneity. Here we show that a modified spectral decomposition can tackle that issue in inhomogeneous power grids in cases where disturbances occur on time scales that are long compared to the intrinsic time scales of the grid. We find in particular that the magnitude of the transient excursion generated by disturbances with long characteristic times does not depend on inertia. For continental-size, high-voltage power grids, this corresponds to power fluctuations that are correlated on time scales of few seconds or more. We conclude that power fluctuations arising from new renewables will not require per se the deployment of additional rotational inertia. We numerically illustrate our results on the IEEE 118-Bus test case and a model of the synchronous grid of continental Europe.

Experimentation and kinetic modeling of low-temperature oxidation of magnesium particles for the production of energy with low environmental impact

Future lack of fossil fuels and global warming stimulate researches on new renewable sources of energy, especially for transportation. With high energy densities, metals appear to be relevant energy carriers. In this study, magnesium powder was considered as a metal fuel for energy production through slow oxidation. Temperature Program Oxidation experiments of magnesium powder were performed using thermogravimetric analyses under four low heating rates (1, 2, 3 and 5 °C min−1). The influence of the particle size was investigated by testing three size fractions (20–50, 50–71 and 71–100 µm). Initial and fully or partially oxidized particles (stopping the reaction at selected conversion rates) were characterized using optical microscopy analyses, which highlighted the different stages of the oxidation mechanism. A three-step kinetic model involving heat transfers was finally proposed to describe the slow oxidation of magnesium and to extract optimal values of the kinetic parameters.

Optimization of extracellular ethanol-tolerant β-glucosidase production from a newly isolated Aspergillus sp. DHE7 via solid state fermentation using jojoba meal as substrate: purification and biochemical characterization for biofuel preparation

BackgroundThe increasing demand and the continuous depletion in fossil fuels have persuaded researchers to investigate new sources of renewable energy. Bioethanol produced from cellulose could be a cost-effective and a viable alternative to petroleum. It is worth note that β-glucosidase plays a key role in the hydrolysis of cellulose and therefore in the production of bioethanol. This study aims to investigate a simple and standardized method for maximization of extracellular β-glucosidase production from a novel fungal isolate under solid-state fermentation using agro-industrial residues as the sole source of carbon and nitrogen. Furthermore, purification and characterization of β-glucosidase were performed to determine the conditions under which the enzyme displayed the highest performance. ResultsA fungus identified genetically as a new Aspergillus sp. DHE7 was found to exhibit the highest extracellular β-glucosidase production among the sixty fungal isolates tested. Optimization of culture conditions improved the enzyme biosynthesis by 2.1-fold (174.6 ± 5.8 U/g of dry substrate) when the fungus grown for 72 h at 35 °C on jojoba meal with 60% of initial substrate moisture, pH 6.0, and an inoculum size of 2.54 × 107 spores/mL. The enzyme was purified to homogeneity through a multi-step purification process. The purified β-glucosidase is monomeric with a molecular mass of 135 kDa as revealed by the SDS-PAGE analysis. Optimum activity was observed at 60 °C and pH of 6.0, with a remarkable pH and thermal stability. The enzyme retained about 79% and 53% of its activity, after 1 h at 70 °C and 80 °C, respectively. The purified β-glucosidase hydrolysed a wide range of substrates but displaying its greater activity on p-nitrophenyl-β-D-glucopyranoside and cellobiose. The values of Km and Vmax on p-nitrophenyl β-D-glucopyranoside were 0.4 mM and 232.6 U/mL, respectively. Purified β-glucosidase displayed high catalytic activity (improved by 25%) in solutions contained ethanol up to 15%. Conclusionβ-glucosidase characteristics associated with its ability to hydrolyse cellobiose, underscore its utilization in improving the quality of food and beverages. In addition, taking into consideration that the final concentration of ethanol produced by the conventional methods is about 10%, suggests its use in ethanol-containing industrial processes and in the saccharification processes for bioethanol production. Graphical abstract▪

Triboelectric nanogenerators (TENG): Factors affecting its efficiency and applications

The demand for energy is increasing tremendously with modernization of the technology and requires new sources of renewable energy. The triboelectric nanogenerators (TENG) are capable of harvesting ambient energy and converting it into electricity with the process of triboelectrification and electrostatic-induction. TENG can convert mechanical energy available in the form of vibrations, rotation, wind and human motions etc., into electrical energy there by developing a great scope for scavenging large scale energy. In this review paper, we have discussed various modes of operation of TENG along with the various factors contributing towards its efficiency and applications in wearable electronics.

Fossil fuels markets in the “energy transition” era

The global energy sector is undergoing a global transformation under the influence of technological breakthroughs in several sectors of production and consumption, as well as profound socioeconomic changes in approaches to energy use. This process became known as “energy transition.” In this paper, the authors investigate the long-term impact of the energy transition and related processes on the markets of key fossil fuels: oil, natural gas, and coal. Research shows that all fossil fuel sectors will face a significant increase in competition, both within traditional markets and from other energy sources, due to the development of inter-fuel competition. At the same time, energy policies and efforts to combat greenhouse gas emissions will mostly determine the energy balances of the largest countries, and will have an even greater impact on the market. Natural gas, as the most environmentally friendly of fossil fuels, with a large potential to supplement the generation of new renewable energy sources (NRES), will be the least impaired by the energy transition. In the next 20 years, its consumption and production are expected to grow significantly. Oil is under serious pressure from environmental legislation and growing inter-fuel competition in the transport sector. It is highly likely that consumption will peak before 2040, yet the depletion of traditional resources is supporting prices. The coal market is set for an almost inevitable reduction in consumption. New technologies for capturing emissions can only partially mitigate the rate of coal use decline.

Spectroelectrochemical Experiment for Studying Water Oxidation with a Nickel Oxide Catalyst

Electrochemical and spectroelectrochemical techniques are very important for characterizing energy materials. In the search for new sources of renewable energy, water splitting for hydrogen production and CO2 reduction is attracting significant attention. These applications require efficient and durable catalysts and a detailed understanding of the underlying catalytic mechanism. Here, we experimentally study electrodeposited nickel oxide as a catalyst for electrochemical water oxidation by combining UV–vis and electrochemical techniques, with emphasis on revealing the interplay between catalytic activity and physical changes in the catalyst. Specifically, the spectroelectrochemical characterization of the catalyst at different pH enables students to establish correlations between catalytic activity, pH, and physical changes in the catalyst. Students are also introduced to fundamental principles of electrocatalysis such as Tafel plots, TOF (turnover frequency), and midpoint potential. Moreover, they are guided toward the reliable interpretation of optical absorption and electrochemical data, along with the conceptual aspects behind these techniques.

Potential of Bioelectricity Generation in Plant-Microbial Fuel Cells Growing House Plants

Although renewable sources of energy including geothermal, hydropower, wind, solar and biomass are utilized by the Philippines, coal-fired power plants remain the main source of electrical energy consumed by Filipino households. To lessen the nation’s dependence on fossil fuels, new and innovative sources of renewable energy should be explored. Plant-Microbial Fuel Cells (PMFCs) are a promising renewable energy technology that can be used to supplement our demand for electricity. PMFCs utilize the metabolic processes of certain bacteria in the roots of a plant to generate clean electricity. This study tested the potential of generating electricity from three common house plants in a PMFC set-up: Spider Plant (Chlorophytum comosum), Portulaca Flower (Portulaca oleracea), and Dumb Canes (Dieffenbachia amoena). A simple set-up was prepared using low-cost materials. Open circuit voltage and current was continuously monitored to determine the power output of the PMFCs. C. comosum registered the highest maximum power density out of the three plants, at 30.39 mW/m2. The results of this study has direct implications to how house plants are kept. Instead of keeping them for aesthetics, the added value of green energy produced can be valuable for powering devices in-situ.

Catalytic Production of Jet Fuels from Biomass.

Concerns about depleting fossil fuels and global warming effects are pushing our society to search for new renewable sources of energy with the potential to substitute coal, natural gas, and petroleum. In this sense, biomass, the only renewable source of carbon available on Earth, is the perfect replacement for petroleum in producing renewable fuels. The aviation sector is responsible for a significant fraction of greenhouse gas emissions, and two billion barrels of petroleum are being consumed annually to produce the jet fuels required to transport people and goods around the world. Governments are pushing directives to replace fossil fuel-derived jet fuels with those derived from biomass. The present mini review is aimed to summarize the main technologies available today for converting biomass into liquid hydrocarbon fuels with a molecular weight and structure suitable for being used as aviation fuels. Particular emphasis will be placed on those routes involving heterogeneous catalysts.

Integrating algae building technology in the built environment: A cost and benefit perspective

Energy consumption rates have been rising globally at an escalating pace since the last three decades. The exploration of new renewable and clean sources of energy globally is thus gaining prime importance. In Australia, coal is still the primary source of energy, which, during the process of energy production, generates greenhouse gases, subsequently resulting in environmental degradation. Within this context, the paper compares the economic and environmental benefits of utilizing two renewable energy production sources: algae building technology (ABT) and solar PV panels. A case study site for retrofitting a specified area on the front façade of a multi-storied building at the University of Technology Sydney, City Campus, Australia was thus chosen for the study. A cost and benefit analysis model using the following performance indicators; return on investment, payback period as well as net present value of the two systems, was thus initiated. Annual revenue generation of both systems which included tangible and intangible benefits of both systems were simultaneously calculated. The investment and operation and maintenance costs of both systems were calculated based on market research as well as quantitative data adapted from our literature review. Our conclusions show that closed tubular photobioreactor systems have more benefit than solar panel system from an environmental impact perspective considering Australia's current struggle with water scarcity, drought, air pollution and carbon emission reduction goals.

Bioconversion on Wastewater of Soybeans using Microbial Fuel Cell

Microbial fuel cell (MFC) is a technology developed to obtain new sources of renewable energy to produce electricity. It can be an alternative for wastewater treatment and bioenergy producers of renewable electricity. This method requires bacteria to convert substrate in wastewater into electrical energy. The mechanism of MFC were oxidation of substrate by bacteria to produce electrons and protons at the anode. The proton in anode chamber passes through a membrane exchange to the cathode chamber, however the electrons couldn’t through. It caused accumulation of electron in anode chamber and then both of electrode had a potential difference, so electron in anode chamber passed through membrane exchange to cathode chamber. In this study used dual-chambers reactors with each compartment having 8 cm × 10 cm × 10 cm of dimensions and 5 mm of thickness. This study was subjected to evaluate the performance of MFC in soybean washing wastewater treatment with bacteria of EM4 to analyze the potentials production of electricity energy. The focus of this study was to evaluate the effect of time to electricity. MFC system was observed for 40 hours, measurement of voltages and electric currents performed every 4 hours. The results showed that there was potential of electricity production from soybean wastewater treatment by MFC. The maximum electricity reached in soybean wastewater media were voltage 441 mV (at 24 h), the electric currents 170 µA and the power density 51, 35 mW/m2 (at 24 h after acclimatization). Increasing of time effect to decreasing of electricity produced.Keywords: bioenergy, electricity, microbial fuel cell, membrane, wastewater soybean

Harvesting Energy from Thunderstorm - A New Source of Renewable Energy - Review

Harvesting Energy from Thunderstorm - A New Source of Renewable Energy - Review

Energy Consumption and Economic Growth: Evidence from Vietnam

The importance of non-renewable, renewable and sustainable energy sources and energy consumption in the economic development strategy of a country is undeniable. The purpose of the paper is to investigate the impacts of energy consumption on the economic growth of Vietnam during the 1980-2014 period. By applying the Autoregressive Distributed Lag (ARDL) model of Pesaran et al. (2001), and the Granger causality test of Toda and Yamamoto (1995), the empirical results provide evidence that electricity consumption has positive impacts on Vietnam's economic growth in both the short run and long run. For public policy prescriptions, the empirical evidence suggests that an exploration of new sources of renewable and sustainable energy is essential for long run economic development.

Current Policy and Technology for Tidal Current Energy in Korea

As global energy consumption continues to increase, the negative impact of global warming also grows. Therefore, eco-friendly energy policy is being established all over the world. Korea’s energy consumption problems are further complicated by the country’s high dependence on energy sourced overseas. Korean energy policy is evolving rapidly to address these problems. Korea has begun to phase out nuclear power and is focusing on developing new sources of renewable energy. So there has been substantial interest in the development of ocean energy. Of all ocean energy technologies, tidal current energy is the closest to the commercialization. Especially, the southwestern coast of Korea is the most promising candidate site for the development of tidal current energy owing to the abundant tidal current energy resource. Meanwhile, ocean energy policy is an important factor in determining the development of ocean energy. Thus, this paper presents the overview of the current status of policy and technology for the tidal current energy system in Korea. These policies explained in this paper can provide significant interest and motivation for the use of tidal current energy resources.

From Waste to Renewable Energy: The Potential of Value and Wealth Creation from Sewage Sludge

Issues and problems in waste management and renewable energy are often linked to development and industrialization. Their implication to people and the environment remain as global issue, particularly in developing countries like Malaysia. This study aims to look into the potential of value and wealth creation by transforming sewage sludge into new source of renewable energy. This study is using qualitative measures. The finding from this qualitative study reveals that, there is a potentiality of value and wealth creation by transforming sewage sludge into energy. Hopefully, this will contribute to green economy practices, which will eventually lead to sustainability of the environment.Keywords: Renewable Energy; Waste; Wealth; SustainabilityeISSN: 2398-4287 © 2018. The Authors. Published for AMER ABRA cE-Bs by e-International Publishing House, Ltd., UK. This is an open access article under the CC BYNC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer–review under responsibility of AMER (Association of Malaysian Environment-Behaviour Researchers), ABRA (Association of Behavioural Researchers on Asians) and cE-Bs (Centre for Environment-Behaviour Studies), Faculty of Architecture, Planning & Surveying, Universiti Teknologi MARA, Malaysia.https://doi.org/10.21834/e-bpj.v3i9.1487

Assessment of Electrical Energy from Pyrolysis of Medical Waste in Jessore City, Bangladesh

Energy crisis and environmental degradation is considered most talked of the topics of modern global development. Medical waste has dangerous impacts on the environment. Besides, load shedding has come to be a great problem in socioeconomic development of Bangladesh for the reason that of the serious electricity crisis. This study also focused on energy recovery potentiality from plastic content of medical waste (PCMW) by converting it into electric energy. This plastic waste integrates an enormous amount of energy and consequently, attention in new renewable sources of energy from these wastes has been augmented, at the present time. Bangladesh as well as Jessore city faces an excessive environmental problem because of improper management of medical waste. This study demonstrated that the medical waste generation rate in Jessore city was found to be approximately 3 ton/day which is about 6.89% of total waste generation in this city throughout the study period. Besides, electric power generation projections from the PCMW were estimated at 74448 kWh per year respectively. This study suggested that appropriate PCMW management policy as well as awareness increasing regarding the management of PCMW is requirement for the development of existing status of living condition.

A Critical Review on Triboelectric Nanogenerator

With the modernization of the technology with time, the demand for energy is increasing day by day, it is necessary to find out the new sources of renewable energy. The fossil fuels upon which the maximum energy has been produced till date are going to be depleted soon. A triboelectric nanogenerator (TENG) is new source of energy firstly demonstrated by Wang et al. in 2012, working basically on the principles of triboelectric effect and electrostatic induction. A triboelectric nanogenerator (TENG) can be used to harvest many forms of energy from the environment which is generally wasted. It has a very simple working mechanism and easy design and can be used to power many small wearable electronics. Many properties of the TENG make it capable of producing large power, and to be used in future for large power generation.

Produksi Bioetanol Dari Limbah Kulit Kopi Menggunakan Enzim Zymomonas Mobilis Dan Saccharomyces Cereviseae

The availability of coffee leather waste is quite large in Aceh, because coffee processing will produce 65% coffee beans and 35% of coffee leather waste, while coffee production in Central Aceh in 2013 reaches a total of 26 thousand tons. Coffee skin waste has fiber content of 65.2%. The purpose of this study is expected to create a new source of renewable energy that is environmentally friendly and can overcome the scarcity of fuel. The process of making bioethanol is done by hydrolyzing the waste of coffee skin into glucose using HCl catalyst. Furthermore, glucose is fermented into bioethanol using Saccharomyces cereviseae and Zymomonas Mobilis bacteria. The variables performed were fermentation time of 5, 7 and 9 days, starter concentration 5%, 10% and 15% and ratio of enzyme combination of Saccharomyces cereviseae and Zymomonas mobilis (1: 2, 1: 1, 2: 1). This study is expected to find the best yield and ethanol content when compared with no enzyme combination

A transversal perspective on global energy production and consumption: An approach based on convergence theory

The transformation of economies and societies associated with technological advances made during the 20th century has not only significantly increased global energy consumption but also placed greater pressure upon production using non-renewable sources. Such circumstances have generated new challenges and urged governments as well as firms to identify and promote new sources of renewable energy. In response to those trends, the chief objective of the study reported here was to analyse the current global framework of the production and consumption of energy obtained from different origins in order to identify opportunities and constraints regarding energy production and consumption that exist among various countries. To that end, data from the World Bank regarding the production and consumption of global energy were analysed in light of the neoclassical and endogenous growth theories of absolute and conditional convergence, respectively, and in terms of panel data models. To reconcile the availability of data across the various countries, data for the period 1990–2013 were used. The data show signs of relevant dispersion among countries and evidence of sigma convergence in the majority of variables associated with global energy supply and demand. Conversely, other evidence indicates a significant absolute convergence of the global production and consumption of energy. Put differently, although significant differences in energy production and consumption among the world’s countries exist, so do signs of convergence, namely, that lower values in some countries are by way of approximation of those verified in countries with higher values. That situation is not necessarily detrimental in terms of renewable sources of energy; however, it is not the case in every context (in some cases the convergence is for the fossil fuel energy, for example). From a strategic perspective, the results recommend policies better customised at the various levels of decision making to promote renewable sources of energy.

The Use of Wood Biomass in the Regional System of Renewable Energy Sources as a Chance for the Region

The world needs energy. It is an obvious truth you do not need to prove. The modern world needs the electricity. With advancing civilization and the rate of consumption, and the demand for electricity is growing. At the same time, conventional resources are running out. This situation leads to the search for new renewable sources of energy. Therefore a crucial role of forests should be taken into consideration. The study shows that, in the relatively short term, the wood biomass (mainly forest) will play a significant role in the regional energy system

Energy production analysis of Common Reed – Phragmites australis (Cav.) Trin.

Abstract Slovakia is acountry with limited natural resources, therefore its essential task is to search for new renewable sources of energy to reduce its dependence on imported fossil fuels. The results of research confirmed that the Common Reed (Phragmites australis (Cav.) Trin.) has considerable potential of phytomass production and energy storage (calorific value reached 17,448 J g−1 d.w.). Biomass production of Common Reed under natural conditions of the lower Liptov region reached 12.702 tons of a dry mater per hectare with the calculated energy storage of 221.622 GJ ha−1. The average biogas production was 351.31 l kg−1 of a dry matter of which the methane (CH4) content represents 185.21 l kg−1 (52.72%). With regards to the values of combustion heat, a calorific value and the production of methane it can also be noted that in case of Common Reed it is more profitable to focus on direct combustion of biomass than the production of biogas and methane.