Effects Of Renewable Energy Sources Research Articles

Fixed head short-term hydrothermal scheduling in presence of solar and wind power

A probabilistic short-term hydro-thermal-wind-photovoltaic scheduling based on point estimate method (PEM) is proposed in this article. To model the uncertainties associated with wind and solar power, point estimate method is used. The Weibull and Beta distributions are employed to handle the uncertain input variables. The mean generation cost of the system is optimized based on an optimization algorithm named crow search algorithm (CSA). Three test systems have been taken, the first test system contains only hydro and thermal plants, and rest of the two systems are based on wind and solar including hydro and thermal unit to investigate the effect of renewable energy sources in the selected test systems. Furthermore, underestimation and overestimation of available wind power has also been included in the problem. The simulation results show that when the penetration of renewable energy sources increases, the mean generation cost decreases. The results obtained by CSA have been compared with other well-known methods. Moreover, the accurate distribution of generation cost for the next day-ahead can be found out using Gram-Charlier series expansion.

Innovative Basis of Research of Energy-Efficient Potential and Effectiveness of Renewable Energy Sources

Innovative Basis of Research of Energy-Efficient Potential and Effectiveness of Renewable Energy Sources

An energy scheduling method for multiple users of residential community connected to the grid and wind energy source

Energy management of residential consumers plays a very important role in the achievement of aim of energy saving, lesser cost of electricity for the residential consumers and highest possible satisfaction of the consumers. In this paper, a common energy scheduler for the multiple users has been designed for energy scheduling of residential consumers having smart appliances. Mathematical modelling of different types of appliances has been done to achieve the required results. Time of use tariff and day ahead real time pricing tariff have been used for energy scheduling. A wind energy source has been considered to reduce the burden of energy demand on the grids and to analyse the effect of renewable energy sources in a small scale energy management problem. A delay factor has been also included in the main objective function of the problem to maintain the satisfaction level of the consumers by reducing cost of waiting. The final designed problem is solved by mixed integer linear programming technique using GAMS software. The time taken for the solution is very less. In this paper, to increase the energy efficiency and the accuracy of the required results, the selected time horizon of 24 h is divided into 96 small time slots, each of 15 min duration. Achievement of the aim of the paper, that is reduction in the cost of electricity and attainment of the highest possible satisfaction level of the users, has been verified by the simulation results. Practical application: Our work is completely applicable in the practical field. This work can be used for the energy scheduling of home appliances.

Investigation of the effects of renewable energy sources on interconnectıon networks

Demand for electricity is increasing due to population growth, the development of technology and the level of prosperity of communities. Coal, natural gas, oil, etc., which are called traditional sources can no longer meet this demand. In addition, these resources are harmful to the environment and have high costs. For all these reasons, the trend towards alternative energy sources is increasing. These sources are called renewable energy sources. Solar, wind, water, geothermal etc. as examples of renewable energy sources. In addition to producing enough energy, it is also necessary to use the produced energy efficiently. This is defined as the energy quality (power quality). The power quality parameters are defined to keep the obtained electric energy within certain limits in terms of quality. These parameters include; harmonic, voltage flicker, voltage deviation etc. Through this study; it has been analyzed, with the increasing number of solar power plants connecting to the network, what kind of changes occurred in the electricity network and how the solar power plants affect the network in terms of energy quality. The analysis was carried out by evaluating the one month data from a 5 MW solar power plant.

THE IMPACT OF RENEWABLE ENERGY SOURCES ON THE ENVIRONMENT IN THE OPINION OF COUNTY RESIDENTS CHOJNICKI

The aim of the study was to present issues of the environmental effects of renewable energy sources. Research was conducted in July 2016 among 269 inhabitants of rural areas of the Chojnice district. A diagnostic survey was employed as the research method. The research showed that renewable energy sources have a positive impact on the environment, and that environmental hazards are not as great as those of conventional energy production. According to the respondents, the greatest environmental damage in the field of RES is related to landscape changes.

Microgrid reliability evaluation considering the intermittency effect of renewable energy sources

Microgrid reliability evaluation considering the intermittency effect of renewable energy sources

Energy on renewable sources: Prospects for the world and for Russia

The outlook for global energy by the mid-21st century will largely depend on nontraditional energy sources, the role of which is growing rapidly already today. Colossal investments in the development of renewable energy sources (RESs) over the past 25–30 years have favored a technological leap, which has reduced the cost of energy by orders of magnitude. Some RESs approached traditional hydrocarbon energy by their economic indicators. The correct economic evaluation of prospects for RES development is a topical scientific and practical problem. Its solution will help, on the one hand, understand and measure the scale and depth of the effects of renewable energy sources on global and domestic energy and, on the other, evaluate the opportunities and prospects for the Russian Federation. The authors of this article analyze trends in RES development in global and domestic practice and recommend improvements to Russian policy in this sphere.

The Effect of Renewable Energy Sources on the Global Power Industry

The global power market is undergoing an important transformation. Successful development of technologies of renewable energy sources (RES) and even a complete switchover of individual countries to those technologies is no longer a technical or economic problem. Some cities, regions and even countries have already set a goal to switch over completely or partially to RES. In the near future, in the power industry the existing trends are expected to consolidate: prices on RES technologies are going to depreciate and the share of RES in the power sector is bound to rise. In Russia, no radical changes on the power market are expected so far: in accordance with the officially approved plan only 6 GW of new REC power stations which are going to ensure 4.5% of the country’s entire power consumption will be built in Russia by 2024.

Non-Aqueous Redox Flow Batteries Based on Polyoxometalates

Renewable energy generation around the world continues to see dramatic growth. According to a recent U.S. Energy Information Administration (EIA) report, 13% of US energy demand in 2013 was met by renewables and the amount is still increasing. Large scale energy storage systems promise to increase the effectiveness of renewable energy sources. Redox Flow Batteries (RFB) represent a highly scalable approach. Traditional RFBs are mostly aqueous which limits their operating voltage range due to water splitting. Non-aqueous systems offer a larger voltage window. Polyoxometalates (POMs), which exhibit versatile redox properties and multiple electron transfers were used as the active species in non-aqueous RFBs. POMs generally contain group 5 or group 6 transition metals linked by oxygen atoms and centered around a heteratom. Common POMs are of the Keggin type ([XM12O40]q−, where X = P, Si, Ge, etc., and M = Mo, W, V, etc. ) or Wells-Dawson type ([X2M18O62]q-). The redox properties of POMs can be altered by exchanging the framework metal atoms or the central heteroatom very easily. Li3PMo12O40, Li4PMo11VO40 and Li6P2W18O62 were tested in acetonitrile and the lithium was chosen as the counter-cation in order to avoid H2 generation. Owing to limitations on the transport rate of Li+ through conventional proton-exchange membranes such as Nafion, an aramid nano-fiber (ANF) membrane was utilized for charge-discharge experiments. The low permeability of ANF prevents the POM crossover, with less than 1% crossover observed after one week. Greater than 85% coulombic efficiency was observed for symmetric cells containing the POMs above, with good reversibility and stability. Both symmetric and asymmetric cells (different POMs utilized for the anolyte and catholyte) were tested. Asymmetric POM-based RFBs hold promise for increasing the voltage window and overall energy density.

Optimal Bidding Strategy and Intramarket Mechanism of Microgrid Aggregator in Real-Time Balancing Market

Microgrid (MG) system with multienergy resources has a wide and dispatchable generation range and shows instant response, therefore, constituting a potentially suitable real-time power balancing resource. In this paper, we introduce the concept of MG aggregator to involve small-scale MGs in real-time balancing market bidding via a hierarchical market framework. At the upper real-time market level, the bidding strategy of aggregator is optimized by a risk-constrained mean-variance model to depress the effects of renewable energy sources (RES) uncertainty; at the lower intramarket level, an event-driven mechanism is presented to reach the cleared quantity of the upper market while realizing maximum economy. Furthermore, the above-centralized self-scheduling problem of MG aggregator is decomposed into individual MG optimization problems to achieve an optimal solution with fast convergence. Simulation results verify that the proposed market framework and the bidding strategy for MG aggregator are of high applicability in real market environment.

Optimal Control of Power Flows and Energy Local Storages in a Network of Microgrids Modeled as a System of Systems

In this paper, a centralized control model for optimal management and operation of a smart network of microgrids (SNMs) is designed. The proposed control strategy considers grid interconnections for additional power exchanges. This paper is based on an original Linear Quadratic Gaussian (LQG) problem definition for the optimal control of power flows in a SNMs. The control strategy incorporates storage devices, various distributed energy resources, and loads. The objective function aims to minimize the power exchanges among microgrids (MGs), and to make each local energy storage system in a MG works around a proper optimal value. The proposed model is evaluated through a case study in the Savona district, Italy, consisting of four MGs that cooperate together under an SNMs connected to a main grid. The case study shows that the proposed approach can effectively cope with the aim to decrease the intermittencies effects of renewable energy sources, and to manage real-time burst in the residential local demands.

Возобновляемая энергетика в ЕС: смена приоритетов

The article analyses the EU policies of promoting renewable energy sources (RES), including the role of state subsidizing and the change of EU policy in 2013. First EU actions in this area were implemented in late 1990s. In mid 2000s the European Commission developed integrated approach of the encouragement of renewables. Promotion of RES was integrated with other areas of the EU energy policies in the framework of the Climate and Energy Package in 2007. The paper evaluates EU achievements and development of particular types of RES in the EU in 2000s. A comprehensive comparative analysis of the cost of different types of RES and the use of incentive measures in the European Union and EU member states is carried out. The conclusion is made that despite the impressive technological progress the renewable energy, with rare exception, is still uncompetitive with the traditional sources of energy in terms of costs. A large-scale state support was the reason for the rapid development of renewables in the EU. Article investigates distorting effects of RES subsidies on the market price of electricity. Feed-in tariffs, investment grants, quotas and tax benefits were the most widespread forms of direct and indirect RES subsidies in the EU. During the economic crisis, these subsidies have become a heavy burden for the budgets of the EU countries and population. Now the EU is modifying its strategy on RES in order to reduce the volume of subsidies. In 2013 European Council substantially changed the priorities of the EU energy policies: instead of «sustainable energy» it accentuated the need to provide a “competitive energy”. Strategic decision to reform the existing methods of RES subsidizing and to develop an «economically reasonable» support scheme was made. The reduction of subsidies will inevitably lead to a sharp reduction in the rate of growth of renewables and the failure to achieve previously agreed EU targets.

Multi-objective stochastic Distribution Feeder Reconfiguration from the reliability point of view

The main purpose of this paper is to assess the DFR (Distribution Feeder Reconfiguration) strategy as a costless technique to enhance the reliability of the distribution systems. The objective functions to be investigated are: SAIFI (System Average Interruption Frequency Index), AENS (Average Energy Not Supplied), total active power losses and the total network cost. In order to observe the effect of renewable energy sources on the reliability of the power system, wind power source as a popular type of renewable energy source is also considered in the system. In addition, to make the analysis more reliable, the uncertainty of the forecast error of active and reactive loads, wind speed variations as well as the failure rate and repair rate parameters are modeled though the probabilistic load flow. Since the problem investigated is a type of discrete, nonlinear and non-convex optimization problem, a novel self adaptive modified optimization algorithm based on the BA (bat algorithm) is proposed too. The proposed self adaptive modification method makes use of three sub-modifications to give each bat (solution) a choice of preferences during the optimization process. The efficiency and feasibility of the proposed method are studied through a standard IEEE (Institute of Electrical and Electronics Engineers) test system.

03/01856 Environmental and economic effects of renewable energy sources use on a local case study: Cosmi, C. et al. Energy Policy, 2003, 31, (5), 443–457

03/01856 Environmental and economic effects of renewable energy sources use on a local case study: Cosmi, C. et al. Energy Policy, 2003, 31, (5), 443–457

Environmental and economic effects of renewable energy sources use on a local case study

Renewable sources represent an effective alternative to fossil fuels for preventing resources depletion and for reducing air pollution. However, their diffusion requires huge capital investment and major infrastructure changes, which have to be assessed to verify their effectiveness. The article present an application of the R-MARKAL model to investigate the feasibility of renewable use on a local case study for electricity and thermal energy production. A comprehensive modelling approach is used to emphasise the relationships and feedback between conversion and demand sectors (residential, services and commercial), taking into account contemporaneously legal issues and physical limits of the system. The model's solutions represent the minimum cost choice and the results show that even in absence of exogenous environmental constraints, many renewable technologies are profitable demand device and their investment costs are paid off in a medium term by lower operating and maintenance expenditures. In this context the use of thermal energy from incinerator allows one to achieve a consistent reduction of atmospheric pollutant emissions and, particularly, of greenhouse gases emissions due to waste degradation.