New Publications are available for Energy resources
http://dl-live.theiet.org
New Publications are available now online for this publication.
Please follow the links to view the publication.Future structure of rural medium-voltage grids for sustainable energy supply
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0762
Due to the fundamental change of the legal framework in Germany [1] and the mandatory targets for renewable energy shares of final energy consumption set by the European Renewable Energy Council [2], the number of distributed renewable generation units in medium-voltage (MV) grids has strongly increased. Especially in rural areas an ongoing dynamic growth of integration of biomass and photovoltaic plants can be expected. In certain situations of injection, parts of rural grids will face overloads and can hardly be operated in line with the technical guidelines. This paper deals with the renewal effort of a rural 20 kV distribution grid with high proportion of renewable energy sources in the next 20 years. To analyze the future problems of voltage stability, scenarios of renewable energy injection of the years 2015 and 2030 have been created. Concrete recommendations for measures in the MV-grid have been developed. Furthermore general recommendations for planning guidelines of MV-grids with a high proportion of renewable energy sources have been derived. (4 pages)Impact of emerging distributed generation facilities on distribution network
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0880
European and national authorities are focusing on renewable energy sources for some time now. Incentives for investments in this domain targeted both development of new sites and bonuses for green energy production so many projects for small energy production plants are now either working or will be commissioned in near future. In contrast, refurbishing of existing distribution network is somehow left behind, causing many setbacks. One reason is that renewable resources are often available in less developed areas on the far end of radial distribution networks. Sustaining current rate of development will become very difficult under current legislative frame without regulation adjustment. First part of our paper present the current situation in one subsidiary of Electrica S.A. , the Romanian distribution company, taking into account both existing facilities and new projects developed in our area. Then, some of available technical solutions are described Third part of this paper covers the influence of new small distributed generators on power quality. PQ monitoring equipments were deployed for each new power plant. Conclusions and future development directions make up the final part of our paper. (4 pages)Customer led network revolution - integrating renewable energy into LV networks using energy storage
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0812
Integrating renewable energy into LV networks brings a number of challenges to existing distribution networks, particularly steady-state voltage rise and in some cases voltage unbalance. Electrical Energy Storage (EES) systems can play an essential role in facilitating renewable energy integration by mitigating voltage rise problems and unbalanced issues. As part of the Customer Led Network Revolution (CLNR) smart grid project, this paper describes research relating to the voltage rise issues arising from large-scale PV integration and presents a solution using EES, based on data analysis from a field trial network, PSCAD simulation and laboratory emulation. (4 pages)Cost-benefit analysis of integration DER into distribution network
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0750
The large integration of DER into distribution system has significantly changed the approach to planning, design and operation of distribution networks. Based on the cost and benefits of three sides (distribution network owner, EDR provider, and electricity user), this paper proposes a elemental calculation approach to analysis the costs and benefits when DER is token as an alternative on network investment to meet special needs for special customer. A test example is used to verify the efficiency and effectiveness of the approach. (4 pages)Integration of demand side management, distributed generation, renewable energy sources and energy storages
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0784
The increasing number of renewable energy sources and distributed generators requires new strategies for the operation and management of the electricity grid in order to maintain or even to improve the power supply reliability and quality. In addition, liberalization of the grids leads to new management structures, in which trading of energy and power is becoming increasingly important. The interconnection of DG inevitably changes the characteristics of the system to which it is being connected, due to the fact that distribution systems were traditionally designed with the assumption of a passive network. The consequence of the integration of DG is that this assumption is no longer valid. There are a number of technical challenges that needs to be addressed. The main objective of this Task is to study how to achieve a better integration of flexible demand (Demand Response, Demand Side Management) with Distributed Generation, energy storages and Smart Grids. (4 pages)Technologies for the integration of electric vehicles in current electrical power system
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0876
The penetration of electric vehicles in the existing electrical power system can be the solution in order to optimize the exploitation of renewable energies and save the current deficiencies suffered in terms of electrical energy storage capacity. Today, with the centralized system of power generation and because of the cost involved in connecting and disconnecting power plants in situations of excess of energy generated against the demand, renewable energy tends to disconnected, with consequent economic loss that it entails. Therefore, the idea of connecting a large number of batteries can be very attractive from the point of view of energy storage in certain moments, when depending on the demand curve, generation may be lost. (4 pages)Potential of small hydro power plants for delivering ancillary services in Germany
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0763
A high penetration of renewable energy sources leads to a higher demand on ancillary services. To ensure the stability of the network, new approaches need to be developed. Small run-of-the-river hydro power plants offer the opportunity to control the network voltage by reactive and active power. Furthermore, the units can participate on the power balancing market to ensure the operation of the transmission system. For this purpose, the main aspects of ancillary services are presented. Especially, the fundamental regulatory requirements for control reserve and for voltage control are descripted. The efficiency of voltage control in medium and low voltage networks by reactive power variation is investigated in a case study. Thereby, the reachable deviation by this control measure is determined considering high feed-in and high load scenarios, respectively. The deliverable control energy of small hydro power plants is estimated and evaluated concerning the fundamental technical aspects. Especially, the potential for the control reserve capacity for each TSO will be analysed. (4 pages)Voltage profile quality of conformance evaluation with process capability analysis in the presence of distributed generation
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0827
Quality is defined as meeting the requirements of the customers, so it is vital for distribution companies to provide electric power with specified voltage in all time for all customers in the competitive energy market. In the absence of distributed generation (DG) it is possible to control voltage profile with proper network design and optimized setting of high voltage transformer online tap changers, but in the presence of DG, especially renewable resource like photovoltaic panels and wind turbines, the voltage profile is affected by stochastic behaviour wind velocity, sun light and DG owners decisions. In this study process capability analysis and statistical control chart have been used together to evaluate of distribution system capability to maintain voltage in design level and to detect abnormalities in voltage profile in the presence of distributed generation. (4 pages)Integration of renewables into the distribution grid needs new software tools for coordination of protective relays
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0709
Traditional software tools developed for distribution system simulation and overcurrent protection coordination need to be revised to cope with the progressive integration of renewable distributed energy resources (DERs) in distribution grid to achieve better relay protection and coordination. Meanwhile, adoption of the microgrid concept results in certain problem for the protective relays using conventional techniques because of the downstream sources that can feed the fault and also the appreciable difference between the utility-grid connected mode and autonomous (islanded) mode. Traditional distribution grid protection is based on the overcurrent scheme with the flow of fault current from the upstream sources. However, the protection confronts with two main issues: firstly, the radial configuration of the distribution network is jeopardized by the distributed resources; and secondly the DERs have a stochastic nature and the contribution of fault current from the downstream is no longer a certain parameter that could be evaluated at the design stage. This paper analyzes the new requirements and strategies expected to be included in the traditional software tools in order to be applicable for the complex future distribution grids. (4 pages)The regulator's role in the integration of renewable power in distribution grids
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0721
The fight against climate change, through rising feed-in tariff policies in France, has resulted in the increase of renewable energy in the electricity production mix. Some of the renewable sources are centralised as in large wind farms for example. Others are decentralised such as photovoltaic panels installed on the roofs of homes. The former are mainly connected to transmission networks and the latter to distribution networks. The number of such installations connected to the French distribution networks has greatly increased since 2008. These individual sources are difficult to predict and control and highly variable. In addition, customers no longer simply consume electricity, but inject it as well, which requires bidirectional flows on networks originally designed to transport electricity in only one direction. (3 pages)Energy resource scheduling considering reactive power management
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0802
The reactive power management is an important task in future power systems. The control of reactive power allows the increase of distributed energy resources penetration as well as the optimal operation of distribution networks. Currently, the control of reactive power is only controlled in large power units and in high and very high voltage substations. In this paper a reactive power control in smart grids paradigm is proposed, considering the management of distributed energy resources and of the distribution network by an aggregator namely Virtual Power Player (VPP). (4 pages)Experiences with the integration of renewable energy sources - from a distribution system to an energy management system
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0904
In Germany the government decided of renewable energy to 80 to raise the amount percent in 2050. Mitteldeutsche Netzgesellschaft Strom (MITNETZ Strom, formerly known as envia Verteilnetz GmbH) as a large distribution system operator in the east of Germany has to handle about 48 percent of renewable energy already today. Until 2020 this ratio is expected to raise to 100 percent and more. So the impacts and challenges for the whole energy system in Germany and Europe for the next decades can be seen today and have to be solved here in the next few years. The author shows the experiences the solutions found in the last years next of MITNETZ Strom, and the tasks for the years. A new generation management system was developed and implemented, new overhead lines and substations were build. The challenges for the future are the optimizing and reinforcement, but also the extension of the existing system. Additionally, the new role of a distribution system operator as a responsible partner for the coordination of system services from renewable plants has to be developed. (4 pages)Real time voltage control in distribution network considering renewable energy sources
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0793
Nowadays, fossil fuels reduction, environmental impacts, transmission line and substation construction costs, economic and technical efficiency, are leading to increase distributed generation such as renewable energy sources (RES). RES are connected to distribution networks (DN), so we don't need to transmission equipment. But the reverse power flow from RES causes to change operation method. As we know weather condition have influence on output power in RES. Conventional control methods are not useful for operation and bus voltage variation damage equipment of network and customer. So we see voltage control is important in DN with RES. So developing in communicating, smart sensors and distribution network automation is made possible for real time control. In this paper we propose a real time voltage and reactive power control in distribution network considering RES. Also fuzzy sets theory is combined with partial swarm optimization algorithm to solve the multiobjective voltage control problem. (4 pages)Optimal placement of sectionalizing switches in distribution network with presence of renewable energy resources
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0882
This paper proposes a method to determine the location of sectionalizing switches in presence of stochastic renewable resources. Particle swarm optimization is used for placement of sectionalizing switches with considering an objective function. The proposed objective function is composed of two terms: minimizing of cost of sectionalizing switches and maximization of reliability benefit. Monte Carlo simulation is used to reliability assessment. The performance of the proposed approach is assessed by a real distribution network. (4 pages)A new paradigm in centralized operation of Portuguese high voltage electric network
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0727
With the continuous increasing of Distributed Generation, we urge to pursuit new solutions to monitor and control the electric network. This paper will present not only the main features of the state of the art GENESys that is operable from de Control Centre at Portuguese Dispatch Centre but also new ideas and innovations to meet this challenge. Since 2004 to 2010 the Portuguese DSO, EDP Distribuicão (EDPD), customer per employee ratio has improved from about 1,0 to 1,7 and the electricity distributed per employee almost doubled during the same period. By the end of 2010 there where, in Portugal, more than 6 million electricity clients, 400 HV/MV Substations, a HV and MV network with more than 82000km and almost 140000km at LV. Also, EDPD is the third largest renewable energy operator in the Iberian Peninsula and the third largest global player in wind energy, through the EDP Renewables (EDPR). (3 pages)Effects of EV-parking lots on transmission lines congestion and price in the electricity market
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0729
Nowadays, the use of distributed energy resources (DERs) is increase to supply loads in power system. EV-parking lots are one of these resources that presence of them in the system can have an influential impact on improvement of operation conditions and electricity price in the market. In this paper, an algorithm is proposed for participation of EV-parking lot in the market and selection of optimal parking. Results show that the presence of EV-parking lots in the electricity market can reduce the market total cost and the congestion costs. (4 pages)Distributed generation, condition for using wind energy in the southern Khorasan province, maintaining and converting wind to the compressed air
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0778
Restructuring in Iranian Electric Power Systems has been caused focusing on Renewable Energy Sources in these systems more than before. Distributed Generation (DG) units may have various effects on the Electrical Power Systems according to their specifications, conditions of operating, and the location of installing. What declares nowadays in this field, is finding the correct location, method of generating power, and the way to connect DG units to the National Grid. In this research, an introduction of DG, its advantages, and the conditions for using DG units in Iran has been discussed and also a survey on Wind Energy in the Southern Khorasan Province and subsequently the usage of Compressed Air in storing Wind Energy have been discussed and analyzed. (4 pages)Optimal operation of distribution network considering renewable energy sources by binary particle swarm optimization and fuzzy theory
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0787
Today, the development of telecommunications infrastructure has led to rapid exchange of data between the distribution network components and the control center. On the other hand, renewable energy sources (RES) are increasing due to deregulation and restructuring in power systems, global warming and reduction of fossil fuels .These sources are connected to the distribution network therefore behavior of these networks will change. One of the most important problems is the optimal operation of the distribution network including renewable energy sources. Optimal operation of distribution network is a mixed integer, nonlinear and multi-objective problem. Therefore in this paper, binary particle swarm optimization and fuzzy set theory are used for solved the problem. Finally, a practical distribution test system is used to investigate the feasibility and effectiveness of the proposed method. (4 pages)Automatic design and optimisation of distribution systems containing renewable energy sources
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0712
This paper addresses the development of a software tool that is able to automatically design and optimise electrical distribution systems containing renewable energy sources. The tool is intended to alleviate the task of system designers and analists with regard to the integration of renewable energy sources and use of energy storage systems into their system. (4 pages)Network active management for load balacing based in a intelligent multi agent system
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0889
More than 1/3 of the EU's power will need to be generated from Renewable Energy Sources (RES) in 2020. This implies a profound transformation of Europe's energy system, grid and markets. The integration of distributed and micro generation in the electricity grid will provide more options for Distribution System Operators (DSOs) to balance their grid areas on the Medium Voltage (MV) and Low Voltage (LV) levels, thereby reducing stress at the Transmission System Operator (TSO) level. At the same time, this will place new requirements on TSOs and DSOs, particularly in terms of operational security. This paper describes the impact of intermittent distributed generation (DG) on distribution grid operation and how load balancing can be used to reduce that impact and to take advantage of it. (4 pages)Quantifying the benefits of DG units in distribution network systems
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0738
Today, with the rise in global energy consumption and thus increase its production CO<sub xmlns="http://pub2web.metastore.ingenta.com/ns/">2</sub> emission has increased sharply. Research shows that one third of the total CO<sub xmlns="http://pub2web.metastore.ingenta.com/ns/">2</sub> emissions are from power plants. Based on the analysis of Energy Technology Perspectives (ETP2008) unless we find an effective way of decreasing CO<sub xmlns="http://pub2web.metastore.ingenta.com/ns/">2</sub> level there will be a 130% increase in CO<sub xmlns="http://pub2web.metastore.ingenta.com/ns/">2</sub> emission by 2050. There are many solutions suggested for preventing the excessive production of environmental contaminants such as increasing energy efficiency, utilizing distributed generators and renewable energy sources. The present study in addition to further introducing distributed generation systems as an effective method for energy production, aims to identify useful indexes for the assessment of these systems in the network, in terms of voltage, losses and environmental impacts. Then a model will be introduced for the assessment the impacts these systems have and also evaluation of the resulted financial benefits for consumers, energy companies and the general community. In the end results of the placement of photovoltaic generators as a type of distributed generation will be evaluated. (4 pages)Probabilistic assessment of constraint volumes on active networks
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0896
Active Network Management (ANM) presents an effective approach to facilitating the connection of renewable generation onto increasingly congested networks. Estimating the severity of constraint experienced by managed generators is a key requirement in order to successfully evaluate the impact of implementing ANM solutions. This paper describes an established method of constraint analysis, its requirements, and outcomes. This approach to constraint analysis is developed further, introducing a probabilistic method for the estimation of curtailment volumes. Examples are provided illustrating the outcomes from such studies. (4 pages)Design and implementation of a solar thermal / photovoltaic energy system
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0739
Toward go green, the main aim of this paper is presentation of a proposal for the integration and implementation of photovoltaic(PV) technologies in buildings considering aesthetic effects, particularized for the Iran through a case study. Our main objective is the selection of the most appropriate technical solution (PV and thermal) for the integration of renewable energy in buildings and electricity grid interconnection in near future. The proposed energy system is employed for energy supply in a residential building for different end uses such as hot water and electricity, a major part of electricity required for lighting, domestic appliances (elevator and electric garage door) that is generated through a PV system. Both the solar thermal and PV systems are installed on the building roof. (4 pages)Directional reactive power undervoltage protection - a protection concept for connecting decentralized renewable energy sources
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0001
With their increasing number, it is getting important that decentralized and renewable energy sources are supporting the stabilization of the system voltage after short voltage dropouts. Often, in the past, these generators were disconnected during network faults. This is not adequate anymore, as it would lead to a loss of a considerable amount of feed-in power. However, if the generators stay connected, it must be ensured that they are not receiving reactive power, as this would lead to a collapse of the grid. In Germany, a number of legal requirements and grid codes are regulating the connection of such generators. These documents also stipulate the use of Directional Reactive Power Undervoltage Protection (Q→& U< protection) that would disconnect such energy sources if they received reactive power during faults on the network. This paper gives an overview about the legal documents and an introduction to the protection function mentioned above. The basic principle of the Q→& U< protection is explained by means of its requirement specifications. Furthermore, the paper will show up standardized test methods evaluating the Q→& U< protection. It will describe how to test the releasing functions, the reactive power direction determination and also all binary inputs and outputs that are necessary for the protection function. (5 pages)Periodic injection of a second harmonic component with Fourier isolation for the detection of power islands
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0349
Distributed Generation (DG) systems include several technologies, many based on renewable energy sources. Due to the intermittent nature of many DG systems, it is necessary to include energy storage devices. This results in a multitude of DG units that require grid connection. Single phase power converters are necessary to achieve connection between domestic scale DG units and the grid. The majority of utility connection standards state that the DG unit must detect a loss of mains (LOM) event and stop feeding energy into the grid. This paper presents a laboratory setup that has been specifically designed to verify the adherence to grid connection standards. Multiple in-the-loop based LOM detection methods are presented, analysed and compared. A harmonic injection technique is introduced and its merits discussed. (5 pages)On-line security assessment and control decision support for large amount wind power integrated power system
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0128
With the integration of large scale wind power, the characteristics of power system operation has been changing, and, some problems come forth. On-line security assessment and control decision support system provides the stability and security state message for dispatcher in time, and, some suggestions to improve the level of power system stability and security. To suit the requirements of large amount wind power integrated power system, the technology of on-line security assessment and control decision support must be modified. This paper focuses on the technology of on-line security assessment and control decision for operation of power system with large scale wind power and designing the support system. In the paper, the study and application of on-line security assessment and control decision support technology in China are introduced. Considering the wind power in China having some distinct characteristics such as large scale, centralized development, long-distance and high voltage transportation, the new requirements to on-line security assessment and control decision support are analyzed. They includes need for new information, on-line modelling with large scale wind farm, transfer limitation calculation under the constraint condition of wind power integration requirement, auxiliary preventive control decision based on the forecasting and adjustment properties of wind power output, coordinated emergency control wind power with hydraulic and thermal power. On the basis of technical rule for connecting wind farm into power grid and the interaction between wind power and power grid, the advices on engineering application of on-line security assessment and control decision support technology for large amount wind power integrated power system, are proposed, for example, with respect to the standard of security assessment and selection of pre-contingency sets. (7 pages)A power electronic transformer based on indirect matrix converter for PWM AC drive with lossless commutation of leakage energy
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0227
High frequency ac link three phase ac to three phase adjustable speed and magnitude PWM ac converters with single stage power conversion and bidirectional power flow are important in the generation of power from renewable energy sources or where isolation is necessary. Due to the use of high frequency these type of converters achieve high power density. Open loop power factor correction, higher efficiency and reliability are important features of these type of converters. One major problem in this type of converter is the commutation of leakage energy which results in power loss, reduction in switching frequency, distortion and loss of output voltage. The topology based on the indirect modulation of matrix converters uses minimum amount of copper and has relatively less number of semiconductor switches. This paper presents a lossless source based commutation strategy along with a modulation technique that minimizes the frequency of leakage inductance commutation. It also results in the soft switching of the output converter (Zero current switching : ZCS). The topology along with the proposed control has been analysed and simulated. Simulation results confirm the operation. (5 pages)Optimal allocation of renewable energy resources for minimising emissions in distribution networks
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0525
Integration of renewable Distributed Generation (DG) into the distribution networks is one of the effective ways to ensure emission reduction with the added benefits of network support and transmission and distribution system expansion deferral. Emission reduction by renewable DGs mostly depends on the generation technology, size and type of DG units and curtailment of fossil fuel based grid energy. This paper proposes a strategy for evaluating the size and type of renewable DG and determining the best mix of different renewable DG technologies by minimising primary and operational emissions without violating network constraints. A methodology based on time sequential optimisation is proposed for maximising annual emission offset considering the time varying demand and generation with different penetration of renewable resources into distribution networks. The proposed technique is tested on a realistic distribution feeder with different scenarios and results are presented. (6 pages)Cost optimal design of micro hydel systems
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0355
Micro hydel systems are turning out to be an important choice for power generation as a renewable energy source, considering the hydel resource available in India. Reports from Ministry for New Renewable Energy (MNRE) states that the estimated potential for power generation in India from hydel plants is about 15,000 MW from 5718 identified sites. Researchers are trying to develop hydel systems with induction generators, operating both in grid-tied and stand-alone modes. This paper describes an optimization model which gives a cost optimized design for micro hydel systems. The model is applied to obtain an optimal design at a typical site in Kerala.Artificial bee colony optimization for combined economic load and emission dispatch
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0386
This paper presents an application of artificial bee colony (ABC) algorithm for multi-objective optimization problem in power system. Considering the environmental impacts that grow from the emissions produced by fossil-fuelled power plant, the economic dispatch that minimizes only the total fuel cost can no longer be considered as single objective. Artificial bee colony algorithm strategy based on mathematical modeling to solve economic, emission and combined economic and emissions dispatch problems by a single equivalent objective function. Artificial bee colony algorithm has been applied to two realistic systems at different load condition. Results obtained with proposed method are compared with other techniques presented in literature. ABC algorithm is easy to implement and capable of searching near global optimum solution at fast convergence and efficiency.Modelling and optimization of renewable energy integration in buildings
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0345
The sustainable security of energy supply, led both developed and developing countries to make and implement new policies to improve efficiency in energy consumption, to adopt new alternatives like renewable energy systems. To face the economic, social, technological and environmental challenges, the need for energy conservation as well as for developing renewable technologies has become even more critical. Hybrid systems can be considered as a reasonable solution, capable to support systems that cover the energy demands of both stand-alone and grid connected consumers. Commonly, it consists of a mix of two or more energy sources used jointly to provide increased system efficiency as well as greater balance in energy supply. The aim of this paper is to present the architecture of a Decision Support System (DSS) that can be used for the hourly energy management of a mix of renewable energy systems. Specifically, an integrated model representing a hybrid energy generation system (characterized by solar plate collector, PV, wind and battery storage) connected to the grid is developed. The approach is based on mathematical modelling of each component, then an optimization problem is solved in order to better manage and control the energy flow so to ensure reliable supply of demand.A three level neutral point clamped Inverter with buck-boost capability for renewable energy sources
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0361
As demand for renewable energy generation increases, the demand for power inverters with voltage buck-boost capability is also expected to rise. This is because the output of renewable energy sources such as solar panel, wind turbines etc are not constant due to varying climatic as well as geographic conditions. So in order to obtain an ac supply with adjustable voltage and frequency, a multi level inverter with buck boost capability is proposed. Multi-level converters are power-conversion systems composed by an array of power semiconductors and capacitive voltage sources that, when properly connected and controlled, can generate a multiple step voltage waveform with variable and controllable frequency, phase, and amplitude. In this a three level neutral point clamped inverter topology is used. Normally a neutral point clamped (NPC) inverter has a disadvantage of input capacitor voltage unbalancing. This can also be avoided by a special arrangement of input capacitors. Alternate Phase Opposition Disposition (APOD) modulation scheme is used for the modulation of NPC bridge. This inverter is used to drive a three phase induction motor. Simulation works are carried out in MATLAB/SIMULINK.Alternate hydro electric dam system called TejWell
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0352
This paper as a solution to world energy needs presents a new type of dam system called TejWell dam. The dam takes advantage of Hydraulics principles to achieve operational objectives. This paper provide a theoretically solution invention of this new kind of dam. Calculations of a prototype dam are provided in this paper which provides for calculation of characteristics needed by dam. The calculations describe how the characteristics of vital parts vary with dam's height and volume. This solution is very much feasible not only on theory and paper but seems practical also. These kinds of dams if built will not cause any ecological disaster. These kinds of dams will also not displace people unlike conventional dams. These dams can be built in sea, rivers, wells, ponds, anywhere where there is water with some depth. So these dams can solve the world energy problem. A theoretical prototype model is calculated in this paper which looks feasible.Global status of renewable energy and market: future prospectus and target
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0356
The World is gradually shifting focus toward its renewable energy resource. Driven by an increasing demand for electricity and widening gap between demand and supply. World has target 800 GW of Renewable power by 2035, Without including Small Hydro power plant and has been enduring a pressing need to reduce its high and increasing greenhouse gas emission. Renewable Energy in the world day by day increases its installation capacity. Renewable electric energy demand has grown by an average 30% per annum over the past 20 years against a backdrop of rapidly declining costs and prices. By early 2010, policy targets for renewable energy at the national level existed in at least 85 countries worldwide, including all 27 European Union member states .Many national targets are for shares of electricity production, typically 5-30 percent, but range from 2 percent to 90 percent. By early 2010, more than two-thirds of the 85 countries with existing national targets were aiming for 2020 or beyond in some manner. Developing countries can virtually stabilize their C02 emissions by 2025 and reduce afterwards, whilst at the same time increasing energy consumption due to economic growth. OECD countries will be able to reduce their emissions by up to 90% by 2050.Theoretical performance prediction of a diesel locomotive based thermoelectric generator
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0452
In recent years researchers have shown interest in development of renewable energy resources and more efficient energy conversion techniques for ensuring sustainable energy supply. Towards more efficient energy utilization approach, generation of thermoelectricity from waste heat forms an attractive tool. Although application in large scale is still limited due to lower conversion efficiency of currently available thermoelectric materials, it is demonstrated by researchers that precisely designed thermoelectric generators may harness significant amount of useful energy, which otherwise re mains untapped and lost forever. In this paper a conceptual parallel flow type Thermoelectric Generation system for Diesel Locomotive exhaust heat recovery is proposed. This paper also presents a one dimensional, steady state, numerical model developed for theoretical performance prediction of the proposed system. Optimistic results were obtained from the theoretical evaluation that supports the idea of developing the system further.Deterministic - renewable energy on road
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0347
World is developing in terms of technology and population, which demands for increased power production. Now much of the energy supplies come from fossil fuels which are non-renewable energy resources. Researches indicate that fossil fuels will be exhausted in around 200 years [1]. Moreover all non renewable energy resources leads to global warming, whose ill effects are well known. Hence the need for renewable energy resources have been well understood and being implemented. This paper discusses a deterministic-renewable source of energy on road transport using EAR (Energy Absorbers on Road). In addition to the hardware (EAR) which is already explored by researchers, this paper discusses the implementation possibilities and quantification has also been attempted on the same. A comparison has also been made with other renewable energy resources. This paper projects this as a practical deterministic source of renewable energy. This paper covers the working principle, implementation possibilities and the experimental output of the proposal.Environmental friendly solar energy in restructured Indian power sector
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0343
Renewable energy sources and technologies have potential to provide solutions to the longstanding energy problems being faced by the developing countries like India. Solar energy can be an important part of India's plan not only to add new capacity but also to increase energy security, address environmental concerns, and lead the massive market for renewable energy. Restructuring has changed the traditional mission and mandates of power utilities in complex ways, and had large impacts on environmental, social, and political conditions for countries like India. The combination of utility restructuring, technology evolution, recent environmental policies provide the bases for renewable to progress an important energy option in near future for India. Only renewables are eligible for support from within their country of origin and count towards that Governments renewable and carbon targets, so there is urgent need to promote renewable in present Indian restructured power sector in sustainable and eco-friendly manner. In this paper, efforts have been made to summarize the availability, current status, strategies, perspectives, promotion policies, major achievements and future potentials of solar energy options in Indian restructured power sector.Scenarios for a Future Electricity Supply: Cost-Optimized Variations on Supplying Europe and its Neighbours with Electricity from Renewable Energies
http://dl-live.theiet.org/content/books/rn/pbrn010e
<p xmlns="http://pub2web.metastore.ingenta.com/ns/">This book pursues the fundamental idea of using renewable energies in a rational and economic way in order to develop a climate-friendly electricity supply. As the most cost efficient solution, an electricity network for the whole of Europe and parts of Africa and Asia must be found. The sources of renewable and partly decentralised electricity generation could be connected in a comprehensive power supply to meet the electricity needs of an entire region. Czisch examines different scenarios for a CO<sub>2</sub> neutral electricity system under different political, technological and economic conditions for Europe and its closer surroundings. The aim is to find in each variation the economically optimal solution, whereby the supply area embraces approximately 1.1 billion inhabitants and an electricity consumption of roughly 4000 terrawatt-hours per annum (TWh/a).</p>A times series model for the aggregate GB wind output circa 2030
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0184
We present a four-season model representing the aggregate output of a possible British wind fleet circa 2030, suitable for providing synthetic wind tune series or a statistical characterisation of the short-term transitional statistics. The model is fitted to historic onshore anemometry data, and adjusted to account for offshore generation and the diurnal component of atmospheric stability variations. (6 pages)Economical assessment of solar electricity from organic photovoltaic systems
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0107
Small size polymeric solar cells at laboratory scale have recently reached efficiencies up to 8.3% [1]. The rapid progress in manufacturing methods which allow a continuous roll-to-roll production indicate that this high efficiency could be within reach for larger modules [2]. Life cycle analysis has evaluated the environmental impact of this emerging technology and allows us to compare the carbon emissions mitigation potential of the polymeric solar technology with other photovoltaic technologies, other renewable energy sources, or fossil fuels [3]. In this work, a detailed economic calculation on the cost of electricity production by a lkWp grid-connected organic photovoltaic system has been performed. Building on the detailed material inventory and the module manufacturing process for the production of organic photovoltaic modules [2], the economical cost of a 1kWp organic photovoltaic system has been calculated taking into account the materials, direct process, labour, balance of system components, design and maintenance costs and using a well established methodology for the economical analysis [4,5]. Assuming values for the performance ratio of the PV system, insolation level, inflation and interest rates, the levelised cost of electricity (LCOE) from an organic photovoltaic system is calculated. The interest of organic photovoltaic technologies is mainly the promise of very low-cost for module components and therefore cheap solar electricity. Our calculation demonstrates that this statement is within reach for an already tested manufacturing process which allows the fabrication of organic photovoltaic modules. The cost of solar electricity is calculated to be 0.26 euro/kWh for 3% efficiency modules of 5 years lifetime, assuming a performance ratio of 0.85 and an insolation of 1700kWh/m2 per year. This reduces to 0.11 euro/kWh if cells with the module reach the current record efficiency of 8.3% and the module lifetime is extended to 10 years. A sensitivity analysis has been performed and it shows the importance of improving the lifetime of the organic PV modules to around 10 years. The cost of electricity from an organic photovoltaic system could be more favourable than that obtained for an equivalent inorganic (silicon-based) system and could attain grid parity in the coming years. (2 pages)Overview of voltage control strategies in medium voltage networks with implementation of distributed generation
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0191
The traditional voltage control in medium voltage networks no longer suffices with the increasing penetration of DG units. This paper will give an overview of possible voltage control strategies for medium voltage networks aiming to maximize the production of renewable energy. Simulations and case studies will be conducted to examine these control strategies and to compare them to the traditional voltage control in medium voltage networks. In this overview, active power curtailment, reactive voltage control and control strategies using the OLTC will be examined. (6 pages)Vehicle to grid and demand side management - an assessment of different strategies for the integration of electric vehicles
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0156
Electric vehicles offer new possibilities for the compensation of large fluctuations caused by renewable energy feed-in. They can be integrated into the electricity grid through different strategies. This study compares non-controlled charging, Demand Side Management and Vehicle to Grid integration strategies with regard to the achievable smoothing of the residual load in the target years 2020 and 2030. Therefore, these strategies are implemented in a temporal resolved model and an indicator for the quality of compensation is developed. The analysis of the results show that significant effects can be achieved with Demand Side Management, especially in 2030. The smoothing effect of Vehicle to Grid is even stronger, although the potential of this integration strategy is not exhausted when it is used for the compensation of fluctuations. (6 pages)Power converters analysis in a renewable energy based hybrid system with hydrogen storage
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0212
This paper presents a hybrid system including a photovoltaic array, a wind turbine, electrolyzers, fuel cells and hydrogen storage tanks, in order to reliably supply a radio base station in isolated locations, where to make a grid connection might be quite expensive. The intermittent and variable energy produced by those different elements must be conditioned in order to fulfil the load demand and requirements. Power converters assume that purpose and their behaviour under different operating situations is simulated to demonstrate how effective they are, even when the generation conditions are intermittent and apparently not reliable. (6 pages)Connecting renewable generation to rural 11KV networks with high levels of voltage unbalance
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0166
This paper looks at the problems of connecting embedded generation in rural networks where high levels of voltage unbalance exist. It discusses the cause of the unbalance and describes its effects. Correcting the unbalance by load balancing is put forward as a long term solution but short term solutions are discussed. These include the use of single phase regulators, over sizing the generator or connecting the generator via an inverter. (4 pages)Optimal offering strategies to the day-ahead market by a wind power producer
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0172
This paper develops a computational tool, based on two-stage stochastic programming, for a wind power producer bidding in the electricity market. The uncertainty related to electricity market prices and wind power production is taken into account. A hybrid intelligent technique, combining wavelet transform, particle swarm optimization and adaptive-network-based fuzzy inference system, enables the generation of scenarios. Besides, risk aversion is considered using the conditional value-at-risk methodology. Computer simulation results are provided and analyzed. Finally, conclusions are duly drawn. (5 pages)Making small high-penetration renewable energy systems work - Scottish island experience
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0186
The power systems on the Scottish islands of Eigg and Foula are presented. These systems were designed by Senergy Econnect Ltd and Wind and Sun Ltd, and make use of SMA's Sunny Island battery inverter to generate a three-phase reference power supply. The renewable generation is sited at various locations around the network, and includes synchronous hydro generation, asynchronous hydro generation, inverter-connected wind turbines, and inverter connected PV arrays. Diesel generators are controlled automatically by the Sunny Island inverters to meet demand when renewable output is insufficient. Autonomous load control equipment allows surplus renewable power to be diverted to heating loads when it is available. The paper identifies the technologies which have made these systems achievable, outlines some issues associated with implementing such systems and highlights lessons learned. (7 pages)Photovoltaic model with MPP tracker for standalone / grid connected applications
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0205
In this study, a novel solar power plant model is proposed. The model is implemented using MATLAB/SIMULINK software package. Perturb and Observe (P&O) algorithm is used for MPP tracker implementation. The dynamic behaviour of the proposed model has been validated by using Sharp's NUS0E3E and Lorentz' mono-crystalline modules in different solar radiation and temperature conditions. Good agreement between the outcomes of the model and the experimental data was achieved. The output characteristics of the PV module under different solar irradiance and temperature are nonlinear. Furthermore, the solar irradiation is unpredictable, which makes the maximum power point (MPP) of the PV module change accordingly. Therefore, a maximum power point tracking (MPPT) technique is needed to operate the PV module at its maximum power point. The developed simulation offers a novel teaching and training tool for undergraduate degree program on renewable power systems. (6 pages)Analysis of reliability aspects of wind power generation in Romania using Markov models
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0173
Wind power has some characteristics that affect its integration into power systems: variability, unreliable accuracy of the output prediction, and the remote insertion into the network. A critical issue facing the integration of the wind power production is the reliable prediction of its contribution to meet the system's load demand. The authors propose to use tools specific for the reliability analysis of the systems, assuming discrete-time Markov processes, with a view to determine reliability index-type of characteristics for the wind power production. (5 pages)Vision 2020+ - strategies for integrating smart renewable power parks with super grid
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0217
In the journey towards 22<sup xmlns="http://pub2web.metastore.ingenta.com/ns/">nd</sup> century, world will be facing severe energy crisis. Supergrid will be required to feed the increasing electricity demand. Supergrid offers the potential to increase penetration of renewable energy resources. This paper provides overview of supergrid and smart renewable energy power parks. The paper will highlight the various technical challenges involved in the integration of renewable power parks with supergrid. The paper will further identify and briefly describe how smart technologies can smooth the integration challenges. Future improvement areas will also be highlighted. (6 pages)Modelling and experimental verification of converter drive system for distributed generation
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0224
Practical research environments can be used to enhance modelling of power system components through measurements. On the other hand, simulation model can enhance the use of laboratory facilities in helping to focus on the most essential cases. This paper describes the validation process of the model developed for converter drive system installed in MultiPower laboratory. Validation results are used to assess the accuracy of modelling. There is a good match between the measurements and simulation results; however some issues regarding the comparison of measurements and simulation results are also discussed. The developed model can be further used to integrate it with other renewable energy resources. (6 pages)