Concepts and Methods to Assess the Dynamic Thermal Rating of Underground Power Cables

With the increase in the electrical load and the progressive introduction of power generation from intermittent renewable energy sources, the power line operating conditions are approaching the thermal limits. The definition of thermal limits variable in time has been addressed under the concept of dynamic thermal rating (DTR), with which it is possible to provide a more detailed assessment of the line rating and exploit the electrical system more flexibly. Most of the literature on DTR has addressed overhead lines exposed to different weather conditions. The interest in the dynamic thermal rating of power cables is increasing, considering the evolution of computational methods and advanced systems for cable monitoring. This paper contains an overview of the concepts and methods referring to dynamic cable rating (DCR). Starting from the analytical formulations developed many years ago for determining the power cable rating in steady-state conditions, also reported in International Standards, this paper considers the improvements of these formulations proposed during the years. These improvements are leading to include more specific details in the models used for DCR analysis and the computational methods used to assess the power cable’s thermal conditions buried in soil. This paper is focused on highlighting the path from the initial theories and models to the latest literature contributions. Attention is paid to thermal modelling with different levels of detail, applications of 2D and 3D solvers and simplified models, and their validation based on experimental measurements. A salient point of the overview is considering the DCR impact on reliability aspects, risk estimation, real-time calculations, forecasting, and planning with different time horizons

Centralised and decentralised control of active distribution systems: models, algorithms and applications.

Power system were traditionally planned and designed by assuming unidirectional power flows from power stations to loads. Nowadays, several factors (e.g., liberalization of the electricity market, need of increased reliability, and environmental issues) lead to a situation where electricity is produced also downstream the transmission level. Connecting generators to the distribution networks could provide several benefits to the whole system, but also technical and safety problems that must be faced. On the other hand, the loads are changing: new loads like electric vehicles and electric pumps are appearing in the network and they are going to modify the electricity consumption; while traditional loads are designed in order to be more efficient, but with additional functions or special features that require more energy. For all these reasons, since 2005, the interest on Smart Grid (electricity network that can intelligently integrate the actions of all users connected to it – generators, consumers – in order to efficiently deliver sustainable, economic and secure electricity supplies) increased. In this framework different techniques to control, operate and thereby integrate distributed energy resources into the network have been analysed and developed. The first technique designed is a centralised control, characterised by a central controller (Distribution Management System) that gathers information like the measures of the main electric parameters, energy price and indicates to DERs (Active Loads, Generators, Energy Storage) the optimal set points minimizing the system cost, subject to technical and economical constraints. The second technique developed is a decentralised control using Multi Agent Systems (MAS). This type of control has been designed and developed for the direct control of active demand and plug-in electric vehicles, managed by the Aggregator, entrusted by the end users to change their consumption habits according to their needs. Moreover, the proposed decentralised MAS, with the active participation of small consumers in the electricity system, support the integration of the Electric Vehicles in the LV distribution network and reduce its harmful impact on voltage regulation. The techniques and the algorithms proposed by the author are analysed and applied in representative Italian Distribution networks, by taking into account the development of the distribution system according to the load profile evolution, providing several examples to underline the importance of the Active Management for deferring the reinforcement of the existing grid infrastructures, increasing the hosting capacity of the networ

Centralised and decentralised control of active distribution systems: models, algorithms and applications.

Power system were traditionally planned and designed by assuming unidirectional power flows from power stations to loads. Nowadays, several factors (e.g., liberalization of the electricity market, need of increased reliability, and environmental issues) lead to a situation where electricity is produced also downstream the transmission level. Connecting generators to the distribution networks could provide several benefits to the whole system, but also technical and safety problems that must be faced. On the other hand, the loads are changing: new loads like electric vehicles and electric pumps are appearing in the network and they are going to modify the electricity consumption; while traditional loads are designed in order to be more efficient, but with additional functions or special features that require more energy. For all these reasons, since 2005, the interest on Smart Grid (electricity network that can intelligently integrate the actions of all users connected to it – generators, consumers – in order to efficiently deliver sustainable, economic and secure electricity supplies) increased. In this framework different techniques to control, operate and thereby integrate distributed energy resources into the network have been analysed and developed. The first technique designed is a centralised control, characterised by a central controller (Distribution Management System) that gathers information like the measures of the main electric parameters, energy price and indicates to DERs (Active Loads, Generators, Energy Storage) the optimal set points minimizing the system cost, subject to technical and economical constraints. The second technique developed is a decentralised control using Multi Agent Systems (MAS). This type of control has been designed and developed for the direct control of active demand and plug-in electric vehicles, managed by the Aggregator, entrusted by the end users to change their consumption habits according to their needs. Moreover, the proposed decentralised MAS, with the active participation of small consumers in the electricity system, support the integration of the Electric Vehicles in the LV distribution network and reduce its harmful impact on voltage regulation. The techniques and the algorithms proposed by the author are analysed and applied in representative Italian Distribution networks, by taking into account the development of the distribution system according to the load profile evolution, providing several examples to underline the importance of the Active Management for deferring the reinforcement of the existing grid infrastructures, increasing the hosting capacity of the networ

Regulating Offshore Electricity Infrastructure in the North Sea:Towards a New Legal Framework

Offshore wind farms need to be connected to the onshore electricity grids of the North Sea coastal states. With an increasing amount of wind farms, it becomes beneficial to construct a meshed offshore electricity grid rather than only single point-to-point lines between the windfarm and the coast. However, the legal framework for offshore electricity infrastructure is currently not yet able to facilitate an offshore electricity grid. Therefore, this dissertation discusses how the legal framework for offshore grid should be changed in order to facilitate the cost-effective development of offshore electricity infrastructure. A main conclusion is that a 'North Sea Agreement' is a suitable instrument. The dissertation analyses the possible contents of such an agreement using a qualitative informal cost benefit analysis

DEMSEE (2007: Istanbul)

It is true that Electricity is a pillar for our present Civilization and Culture. One should also recognize that Electricity is the finest useable form of Energy and therefore the most precious. Deregulation of Electricity Markets aims ultimately to make almost everyone responsible for the way electricity is generated, distributed and used. It aims to let fair market rules result in a Market Operation that will advance this sense of responsibility for everybody. This is particularly important in view of the present delicate state of the Environment which should for Humanity’s sake be preserved, at all costs. And indeed, we are lucky in the sense that the current Information Technologies and Information and Communication Technology will allow us to live up to our responsibilities concerning rational electricity usage as well as the preservation of the environment. However, a strong, wide and lasting commitment is necessary, i.e. political will by every nation, to achieve progress with respect of the environment. ...ELECTRIC POWER SUPPLY: THE ENGINEERING CHALLENGES AND THE CONTRIBUTION OF CIGRE / Jean KOWAL, 1 -- SUBSIDIES IN WHOLESALE ELECTRICITY MARKET / Osman SEVAİOĞLU, 8 -- GASEOUS DIELECTRICS IN POWER TRANSMISSION AND DISTRIBUTION / Loucas G. CHRISTOPHOROU, 13 -- INFRASTRUCTURE DEVELOPMENT AND POWER SYSTEM SECURITY ISSUES IN A LIBERALIZED ENVIRONMENT IN SOUTH-EASTERN EUROPE (SEE) -- Evangelos LEKATSAS, 20 / NATURAL HAZARDS, GLOBAL CLIMATE CHANGE AND ENERGY PRODUCTION -- Menas KAFATOS, 27 / EDUCATIONAL EXPERIMENT KIT STUDIES ON RENEWABLE ENERGY SOURCES -- Özcan ATLAM, 32 / AN EFFECTIVE SET OF I.C.T. TOOLS FOR TEACHING & LEARNING OF RENEWABLE ENERGY SYSTEMS (RES) -- S. KAPLANIS, E. KAPLANI, 41 / A GIS WEB – APPLICATION FOR POWER SYSTEM OF CRETE -- J. SYLLIGNAKIS, C. ADAMAKIS, T.M. PAPAZOGLOU, 48 / DIAGNOSTIC REVIEW OF A BLACKOUT IN RHODES -- T. M. PAPAZOGLOU, E.J. THALASSINAKIS, C. TSICHLAKIS, N.D. HATZIARGYRIOU, 55 / REAL-TIME TRANSFORMER DYNAMIC LOADING APPLICATION-IMPLEMENTATION AND PRACTICAL USE -- S. KRSTONIJEVIĆ, N. ČUKALEVSKI, G. JAKUPOVIĆ, N. DAMJANOVIĆ, S. CVETIĆANIN, 62 / A COMPARISON OF THE PERFORMANCE RATIO OF PHOTOVOLTAIC MODULES AT DIFFERENT TILT ANGLES -- E. DRAKAKIS, F. MAVROMATAKIS, Y. RANGHIADAKIS, P. TZANETAKIS and I. FRAGIADAKIS, 69 / ON THE MAXIMIZATION OF THE COST-EFFECTIVENESS OF A PV PLANT -- S. KAPLANIS, E. KAPLANI, 75 / INTEGRATED SOFTWARE, FOR IMPULSE VOLTAGES ESTIMATION, IN HIGH VOLTAGE NETWORKS WITH DISTRIBUTED GENERATION -- Stavros LAZAROU, Eleftheria PYRGIOTI, Dimosthenes AGORIS, 83 / NEW 400 kV INTERCONECTION OHL KOSOVO - ALBANIA AND TRANSMISSION NETWORK CONCEPT OF KOSOVO -- S. LIMARI1, K. BAKIC, K. ROBO, L. AHMA, 92 / DEREGULATED ELECTRICITY MARKET IN SOUTH – EASTERN EUROPE: ACTIVE NETWORKS -- Venizelos EFTHYMIOU, 102 / CO2 EMISSIONS FROM THE USE OF FOSSIL FUELS IN CRETE – GREECE -- John VOURDOUBAS, Antonios PITARIDAKIS, Charalampos LITOS, 109 / SURVEY OF POWER EXCHANGES – ORGANIZATION AND RESPONSIBILITIES -- O. GJERDE, O.B. FOSSO, 1J. BOGAS, 114 / FREQUENCY PERFORMANCE MONITORING AND ANALYSIS IT SUBSYSTEM FOR a TSO’s CONTROL CENTRE: ARCHITECTURE AND INITIAL EXPERIENCE WITH ITS USE -- Goran JAKUPOVIĆ, Ninel ČUKALEVSKI, Nikola OBRADOVIĆ, 121 / MARIN POLLUTION AND EFFECTIVE USE OF THE RTV SILICON COATINGS IN CRETAN POWER SYSTEM -- Emmanuel J. THALASSINAKIS, 128 / MONTE CARLO PROCEDURES FOR SIMULATING REAL TIME CONTINGENCES AND SETTING OPTIMAL REDISPATCHING STRATEGIES IN MULTI-AREA SYSTEMS -- S. BENINI, A. LEONI, P. PELACCHI, D. POLI, 136 / COMPARING DIFFERENT APPROACHES TO SOLVE THE UNIT COMMITMENT PROBLEM CONSIDERING HYDRO-PUMPED STORAGE STATIONS -- Yiannis A. KATSIGIANNIS, Emmanuel S. KARAPIDAKIS, 147 / ROOF INTEGRATED SOLAR PARABOLIC COLLECTORS SIMULATION ANALYSIS -- G. BARAKOS, S. KAPLANIS, M. PETRAKIS, A. SPYROGIANNOULAS, 154 / THE ROLE OF A POWER EXCHANGE FOR ENERGY TRADING AND POWER GENERATION INVESTMENT -- Bakatjan SANDALKHAN, 161 / HEURISTIC BASED SYNCHRONOUS GENERATOR EXCITATION CONTROL FOR USE IN A DEREGULATED ENVIRONMENT OF ISLAND POWER SYSTEMS -- Yannis L. KARNAVAS, Nicolaos P. POLYZOS, 169 / INNOVATIVE EDUCATION, TRAINING AND DEVELOPMENT PRACTICES AT THE ELECTRICITY AUTHORITY OF CYPRUS -- George ASHIKALIS, 177 / WIND FARMS EXPERIENCE IN CRETE ISLAND -- Antiopi GIGANTIDOU, Ioannis STEFANAKIS, N.D. HATZIARGYRIOU, 186 / PUBLIC KEY INFRASTRUCTURE AS A NEW TECHNOLOGY ENABLING ELECTRONIC AUCTIONS USED IN THE CONTEXT OF ELECTRICITY MARKET RESTRUCTURING: AN ASPECT OF THE COMPLEX GLOBAL ECONOMY -- John K. SAKELLARIS, 195 / THE LIBERALIZATION OF THE ELECTRIC POWER MARKET IN SOUTH – EASTERN MEDITERRANEAN -- Dimitris SARRIS, 202 / DETERMINATION OF COST STAGES OF TRANSMISSION LINE PRODUCTS FROM LONDON METAL EXCHANGE TO FINAL CONSUMER -- Sedat KARABAY, Ahmet ŞEN, 205 / NON-INTRUSIVE, ON-LINE RESIDENTAL METERING BASED ON BROADBAND COMMUNICATION -- Ali İNAN, Themis PAPASTERGIOU, 213 / CONTRIBUTION OF LANDFILL GAS ELECTRICITY GENERATION TO ENERGY BALANCE OF CRETE ISLAND: AN ECONOMIC, ENVIRONMENTAL AND SUSTAINABLE ASSESSMENT USING LEAP MODEL -- A. A. TSAVE, E. S. KARAPIDAKIS, P. M. SOUPIOS, 2181st ed

Economics of Electricity Battery Storage

This chapter deals with the challenges and opportunities of energy storage, with a specific focus on the economics of batteries for storing electricity in the framework of the current energy transition. Storage technologies include a variety of solutions that have been used for different grid services, including frequency control, load following, and uninterrupted power supply. A recent interest is being triggered by the increasing grid balance requirements to integrate variable renewable sources and distributed generation. In parallel, lithium-ion batteries are experiencing a strong market expansion driven by an uptake of electric vehicles worldwide, which is leading to a strong decrease of production costs, making Li-ion batteries an attractive solution also for stationary storage applications

The Palgrave Handbook of International Energy Economics

This open access handbook is distinguished by its emphasis on international energy, rather than domestic energy policies or international geopolitic aspects. Addressing key topics such as energy production and distribution, renewables and corporate energy structures, alongside global energy trends, regional case studies and emerging areas such as the digitalization of energy and energy transition, this handbook provides a major new contribution to the field of international energy economics. Written by academics, practitioners and policy-makers, this handbook is a valuable and timely addition to the literature on international energy economics. This book was published open access with the support of Eni