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Hydrogen Smart-Grids: Smart Metering of Electricity from Hydrogen Fuel Cells  [PDF]
Gopalakrishnan Kumar, Serhan Demirci, Chiu-Yue Lin
Journal of Sustainable Bioenergy Systems (JSBS) , 2013, DOI: 10.4236/jsbs.2013.32022
Abstract:

In the last decade, increasing applications of information technology (IT) within power industry has become a significant reality. As distributed power networks are gaining importance and renewables are getting a bigger ratio within energy production, Smart Grid applications have become essential, especially due to the intermittent nature of renewable energy resources. Smart Grid is a sustainable energy system that measures, checks, and controls the generation, transmission, and consumption of electrical energy in grids on all voltage levels. Smart Grid experts are driving forward the development of effective communication and information technologies for the build-up of intelligent power supply networks. Examples of these are control systems for the realization of virtual power plants, intelligent consumer data acquisition systems, and smart distribution management systems. Fuel cell-based hydrogen electricity, in comparison to other renewable energy sources, is more stable and predictable. Yet hydrogen power and smart-grids have many application points, mainly as means of energy storage. This study claims that hydrogen energy and smart-grids could also engage through an appliance of IT managed metering of hydrogen power production. Smart metering and management of hydrogen fuel cells would enable advanced planning of short-to-mid-term power productions and thus foster use of hydrogen power within distributed networks, as local community or industrial applications.

Current challenges for efficient electricity grids
Ruth Klüser
Poiesis & Praxis , 2009, DOI: 10.1007/s10202-009-0070-x
Abstract: The comprehensive liberalisation of the electricity market at the end of the last century has initiated a dynamic development. The politically determined disjunction of the network operation from generation, commerce and distribution which broke open the value added chain concerning the business organisation is to induce competition and consequently lower prices. Thus, besides a secure electricity supply, profitability, efficiency, quality and environmental aspects constitute present aims and have led to an enormous increase of complexity in the power supply. Furthermore, the imponderability and uncertainty of competition processes in a liberated market aggravate prognoses for future investment decisions. Not least the anymore rising electricity demand, the emerging of a single European power market as well as technically pushed changes in the production structure, due to the emergence of alternative forms of power generation such as wind or solar energy, biomass energy or fuel cells, account for electric networks which afford complex planning and regulation mechanisms. This article gives a survey of various requirements posed on electricity networks and concludes with a short description of solution approaches to safeguard a cost-saving and secured future electricity supply.
Long-range Response in AC Electricity Grids  [PDF]
Daniel Jung,Stefan Kettemann
Physics , 2015,
Abstract: Local changes in the topology of electricity grids can cause overloads far away from the disturbance, making the prediction of the robustness against changes in the topology - for example caused by power outages or grid extensions - a challenging task. The impact of single-line additions on the long-range response of DC electricity grids has recently been studied. By solving the real part of the static AC load flow equations, we conduct a similar investigation for AC grids. In a regular 2D grid graph with cyclic boundary conditions, we find a power law decay for the change of power flow as a function of distance to the disturbance over a wide range of distances. The power exponent increases and saturates for large system sizes. By applying the same analysis to the German transmission grid topology, we show that also in real-world topologies a long-ranged response can be found.
Delocalization of Phase Perturbations and the Stability of AC Electricity Grids  [PDF]
S. Kettemann
Physics , 2015,
Abstract: The energy transition towards an increased supply of renewable energy raises concerns that existing electricity grids, built to connect few centralized large power plants with consumers, may become more difficult to control and stabilized with a rising number of decentralized small scale generators. Here, we aim to study therefore, how local phase fluctuations affect the AC grid stability. To this end, we start from a model of nonlinear dynamic power balance equations. We map them to complex linear wave equations and find stationary solutions for the distribution of phases $\varphi_i$ at the generator and consumer sites $i$. Next, we derive differential equations for deviations from these stationary solutions. Next, we derive differential equations for deviations from these stationary solutions. Starting with an initially localized phase perturbation, it is found to spread in a periodic grid diffusively throughout the grid. We derive the parametric dependence of diffusion constant $D$. We apply the same solution strategy to general grid topologies and analyse their stability against local fluctuations. The fluctuation remains either localized or becomes delocalized, depending on grid topology and distribution of consumers and generators $P_i$. Delocalization is found to increase the lifetime of phase fluctuations and thereby their influence on grid stability, while localization results in an exponentially fast decay of phase fluctuations at all grid sites.
Power Management using PLC and SCADA
Roshan Bhaiswar,Ambarish A. Salodkar,Pravin Kshirasagar
International Journal of Engineering Innovations and Research , 2012,
Abstract: Operation, control and protection system can be implemented to cover various industries starting from small scale industries to wide area operation and controlling. Power Control operation with Supervisory Control Data Acquisition (SCADA) System is mandatory to run smooth heater control in industries. High scale SCADA system with enhanced features not only used for wide area system operation, but also covers Distribution Management System (DMS), Energy Management System (EMS), various Network Applications and Metering Management systems. This implementation includes power management for such industries using PLC and SCADA system. Control algorithm measures critical parameters and adjust variable outputs to optimize power by turning ON/OFF the heater with improved performance. Further electricity cost further reduces by around 5 20PLC and SCADA is used to model and realize the complete system and perform the experiment for result analysis.
An assessment of billing electricity consumers via analogue meters in Kano, Nigeria, by Kano electricity distribution plc
L Abdulwahab
Bayero Journal of Pure and Applied Sciences , 2009,
Abstract: This paper assesses the perception of billing consumers via analogue meter in Kano Electricity Distribution Plc, Nigeria. Questionnaire survey was used to collect data from the consumers, frequency counts and percentages were used to analyze the generated data. The result of the study revealed that 38% of the Analogue meters were installed between eleven to twenty one years ago; hence the need for replacement of obsolete meters and periodic inspection of all consumers’ meters at least once in three months for proper reading is vital in order to achieve accurate billing. The study also revealed poor and unreliable power supply and most often the bills issued for the electricity consumption are based on estimates, thus contributing to poor consumers’ response to payments of electricity bills. Some suggestions that can facilitate the improvements of the operation of the Distribution Company were offered.
Review of DC System Technologies for Large Scale Integration of Wind Energy Systems with Electricity Grids  [PDF]
Sheng Jie Shao,Vassilios G. Agelidis
Energies , 2010, DOI: 10.3390/en3061303
Abstract: The ever increasing development and availability of power electronic systems is the underpinning technology that enables large scale integration of wind generation plants with the electricity grid. As the size and power capacity of the wind turbine continues to increase, so is the need to place these significantly large structures at off-shore locations. DC grids and associated power transmission technologies provide opportunities for cost reduction and electricity grid impact minimization as the bulk power is concentrated at single point of entry. As a result, planning, optimization and impact can be studied and carefully controlled minimizing the risk of the investment as well as power system stability issues. This paper discusses the key technologies associated with DC grids for offshore wind farm applications.
Long-Range Response to Transmission Line Disturbances in DC Electricity Grids  [PDF]
Darka Labavi?,Raluca Suciu,Hildegard Meyer-Ortmanns,Stefan Kettemann
Physics , 2014, DOI: 10.1140/epjst/e2014-02273-0
Abstract: We consider a DC electricity grid composed of transmission lines connecting power generators and consumers at its nodes. The DC grid is described by nonlinear equations derived from Kirchhoff's law. For an initial distribution of consumed and generated power, and given transmission line conductances, we determine the geographical distribution of voltages at the nodes. Adjusting the generated power for the Joule heating losses, we then calculate the electrical power flow through the transmission lines. Next, we study the response of the grid to an additional transmission line between two sites of the grid and calculate the resulting change in the power flow distribution. This change is found to decay slowly in space, with a power of the distance from the additional line. We find the geographical distribution of the power transmission, when a link is added. With a finite probability the maximal load in the grid becomes larger when a transmission line is added, a phenomenon that is known as Braess' paradox. We find that this phenomenon is more pronounced in a DC grid described by the nonlinear equations derived from Kirchhoff's law than in a linearised flow model studied previously in Ref. \cite{witthaut2013}. We observe furthermore that the increase in the load of the transmission lines due to an added line is of the same order of magnitude as Joule heating. Interestingly, for a fixed system size the load of the lines increases with the degree of disorder in the geographical distribution of consumers and producers.
Hybrid Power System about Wind and Electricity Based on PLC
基于 PLC 的风电混合动力系统

LI Wen-Jiang,HUANG Guan,LIU Nan,AN Bai-Feng,
李文江
,黄冠,刘南,安柏峰

计算机系统应用 , 2012,
Abstract: In order to solve the problem about the utilization of wind resources in industrial production in the past was insufficiently,we designed the wind hybrid systems based on PLC,and it opened up a new space of the development of the wind power.Based on wind turbine,the system drive the air compressor with the supplement of electric motors,storing the compressed air to air storage tank,which has an inner drive served as the cylinder of the executing agency and operating steadily as demanding,to realize the energy savings finally.PLC is the core,machinery is base,pneumatic system output energy in this system,and typical test results obtained through the system test.There are lots of advantages in this system,such as good safety,lower cost,easy to maintain,no noise and pollution.It can be popularized widely,and it also adapt to the demand of energy conservation and emission reduction,what's more,it has a good market prospect.
Intelligent Metering for Urban Water: A Review  [PDF]
Thomas Boyle,Damien Giurco,Pierre Mukheibir,Ariane Liu,Candice Moy,Stuart White,Rodney Stewart
Water , 2013, DOI: 10.3390/w5031052
Abstract: This paper reviews the drivers, development and global deployment of intelligent water metering in the urban context. Recognising that intelligent metering (or smart metering) has the potential to revolutionise customer engagement and management of urban water by utilities, this paper provides a summary of the knowledge-base for researchers and industry practitioners to ensure that the technology fosters sustainable urban water management. To date, roll-outs of intelligent metering have been driven by the desire for increased data regarding time of use and end-use (such as use by shower, toilet, garden, etc.) as well as by the ability of the technology to reduce labour costs for meter reading. Technology development in the water sector generally lags that seen in the electricity sector. In the coming decade, the deployment of intelligent water metering will transition from being predominantly “pilot or demonstration scale” with the occasional city-wide roll-out, to broader mainstream implementation. This means that issues which have hitherto received little focus must now be addressed, namely: the role of real-time data in customer engagement and demand management; data ownership, sharing and privacy; technical data management and infrastructure security, utility workforce skills; and costs and benefits of implementation.
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