Distributed Power Generation in Europe: Technical Issues for Further Integration

The electric power sector in Europe is currently facing different changes and evolutions mainly in response to the three issues at EU level - environmental sustainability, security of supply, and competitiveness. These issues, against a background of growing electricity demand, may represent drivers for facilitating the further deployment of Distributed Power Generation technologies in Europe. The present Report focuses on the potential role of Distributed Power Generation (or simply Distributed Generation, DG) in a European perspective. More specifically, this work aims to assess the technical issues and developments related to DG technologies and their integration into the European power systems. As a starting point the concept of Distributed Generation is characterised for the purpose of the study. Distributed Generation, defined as an electric power source connected to the distribution network, serving a customer on-site or providing network support, may offer various benefits to the European electric power systems. DG technologies may consist of small/medium size, modular energy conversion units, which are generally located close to end users and transform primary energy resources into electricity and eventually heat. There are, however, major issues concerning the integration of DG technology into the distribution networks. In fact, the existing distribution networks were not generally designed to operate in presence of DG technologies. Consequently, a sustained increase in the deployment of DG resources may imply several changes in the electric power system architecture in the near future. The present Report on Distributed Generation in Europe, after an overview of the basic elements of electric power systems, introduces the proposed definition and main features of DG. Then, it reviews the state-of-the-art of DG technologies as well as focuses on current DG grid integration issues. Technical solutions towards DG integration in Europe and developments concerning the future distribution systems are also addressed in the study.JRC.F.7-Energy systems evaluatio

Gene amplification as double minutes or homogeneously staining regions in solid tumors:Origin and structure

Double minutes (dmin) and homogeneously staining regions (hsr) are the cytogenetic hallmarks of genomic amplification in cancer. Different mechanisms have been proposed to explain their genesis. Recently, our group showed that the MYC-containing dmin in leukemia cases arise by excision and amplification (episome model). In the present paper we investigated 10 cell lines from solid tumors showing MYCN amplification as dmin or hsr. Particularly revealing results were provided by the two subclones of the neuroblastoma cell line STA-NB-10, one showing dmin-only and the second hsr-only amplification. Both subclones showed a deletion, at 2p24.3, whose extension matched the amplicon extension. Additionally, the amplicon structure of the dmin and hsr forms was identical. This strongly argues that the episome model, already demonstrated in leukemias, applies to solid tumors as well, and that dmin and hsr are two faces of the same coin. The organization of the duplicated segments varied from very simple (no apparent changes from the normal sequence) to very complex. MYCN was always overexpressed (significantly overexpressed in three cases). The fusion junctions, always mediated by nonhomologous end joining, occasionally juxtaposed truncated genes in the same transcriptional orientation. Fusion transcripts involving NBAS (also known as NAG), FAM49A, BC035112 (also known as NCRNA00276), and SMC6 genes were indeed detected, although their role in the context of the tumor is not clear

Targeted HVDC Deployment for a Sustainable European Transmission System Development

Against a background of energy market restructuring, increasing environmental awareness and rising concerns about security of energy supply, the electric power system in Europe is facing several issues. Indeed, the general increase of inter- and intra-zonal power transactions and the constant growth in electricity demand in Europe are currently putting the entire electric system under strain. Such issues have been traditionally addressed by adding new capacity, with investments particularly in the field of large-size generation and high voltage Alternating Current (AC) transmission infrastructures. Nowadays, increasing the power system capacity is frequently a challenging option due to economic, environmental, and political constraints that hinder the construction of new large power plants and high voltage lines. To address the above issues new solutions are therefore necessary. Among them, one of the most promising foresees the targeted deployment of HVDC (High Voltage Direct Current) transmission technologies displacing the conventional high voltage AC ones. When comparing HVDC with AC, for the same transmitted power the need for right of way is much smaller for HVDC than for AC. The environmental impact as a whole may then be smaller with HVDC. On the other side, a techno-economic assessment needs to be carefully carried out. HVDC technology presents characteristics that have made it widely attractive over AC transmission for specific applications like long-distance power transmission and long submarine cable links. Currently, recent advances in the power electronics coupled to the traditional features of HVDC may lead to improve the operation and sustain the development of the European transmission grid. In fact, the application of VSC (Voltage Source Converter)-based HVDC can provide the European power system with an increased transmission network capacity and generally enhanced system reliability, security and controllability. These properties are especially important in a deregulated environment, where VSC-based HVDC with its fast power flow control capability can be an attractive option to solve several transmission problems. The present paper aims at investigating the impact of VSC-based HVDC on the European power systems, focusing on the technical, environmental, and economic benefits given by the deployment of these devices. Specific attention is paid to the transmission capacity enhancement attainable by VSC-HVDC in targeted applications in the European transmission system. Towards this scope, the modeling of these VSC-HVDC technologies for steady-state studies becomes essential. An original model of these devices is introduced in the paper. Then, a techno-economic analysis of the impact of VSC-HVDC on liberalized power systems in Europe is undertaken to investigate the feasibility and the sustainability of such investment compared to building AC lines.JRC.F.7-Energy systems evaluatio

Automated energy management in distributed electricity systems: An EEPOS approach

The increasing capacity of distributed electrical generators brings new challenges in maintaining a high security and quality of electricity supply. New techniques are required for grid support and power balance. The highest potential for these techniques is to be found on the part of the electricity distribution grid. This article addresses this issue and presents the EEPOS project’s approach to automated management of flexible electrical loads in neighbourhoods. The management goals are (i) maximum utilisation of distributed generation in the local grid, (ii) peak load shaving/congestion management, and (iii) reduction of electricity distribution losses. Contribution to the power balance is considered by applying two-tariff pricing for electricity. The presented approach to energy management is tested in a hypothetical sensitivity analysis of a distribution feeder with ten households and ten photovoltaic (PV) plants with an average daily consumption of electricity of 4.54 kWh per household and a peak PV panel output of 0.38 kW per plant. Energy management shows efficient performance at relatively low capacities of flexible load. At a flexible load capacity of 2.5% (of the average daily electricity consumption), PV generation surplus is compensated by 34%-100% depending on solar irradiance. Peak load is reduced by 30% on average. The article also presents the load shifting effect on electricity distribution losses and electricity costs for the grid user.JRC.C.3-Energy Security, Distribution and Market

Sustainability Analysis of VSC-HVDC in the Liberalised European Power System - a Practical Case

The present paper aims at investigating the impact of the emerging Voltage Source Converter-based High Voltage Direct Current (VSC-HVDC) technology on the liberalised power system in Europe. In particular, focus is on key technical, economic, and environmental features of VSC-HVDC. A techno-economic analysis on a European priority interconnection project (i.e. the planned tie line Poland-Lithuania) is undertaken, so as to compare the economic and environmental sustainability of an investment in VSC-HVDC with other options.JRC.F.3-Energy securit

Modeling and Application of VSC-HVDC in the European Transmission System

The present paper focuses on the technical, environmental, and economic features of VSC-based HVDC technologies. The aim is to investigate the impact of VSC-HVDC on the European power system: specific attention is paid to the transmission capacity enhancement attainable in targeted applications. Towards this purpose, an original steady state model of the VSC-HVDC is presented and tested. Then, a techno-economic analysis of the impact of VSC-HVDC on liberalized power systems in Europe is undertaken so as to investigate the feasibility and the sustainability of such investment, also compared to building HVAC lines.JRC.DDG.F.3-Energy securit

Evoluzione della Generazione Distribuita in Europa

Il crescente livello di penetrazione delle risorse di Generazione Distribuita nelle reti elettriche europee pone numerose sfide, sia tecniche, sia regolatorie, al fine di garantirne un'efficace integrazione nei sistemi elettriciJRC.F.7-Energy systems evaluatio

The Impact of DG on European Electricity Grids

Integration of distributed generation into Europe's electricity networks may be feasible, but the design of distribution grids in particular needs to evolve towards new models, in order to avoid medium-term problems. Following on from their first article (COSPP September-October 07), Angelo L'Abbate, Gianluca Fulli and Stathis D. Peteves consider the issues and options.JRC.F.7-Energy systems evaluatio

Power Distribution Systems in Europe: Present Status and Challenges towards a further Integration of Distributed Generation

In response to energy market restructuring, environmental pressures, and concerns about the security of energy supply, the European electric power system, both at transmission and distribution level, is experiencing changes in the operation mode and facing renovations in the architectural design. At transmission level, the bulk power system expansion - in terms of new large-scale generation and added transmission capacity, both needed to adequately meet the increase in electricity demand - is curbed by techno-economic, environmental, and social constraints. At distribution level, a number of recent trends offer the potential to overcome some of the major constraints on the upstream transmission/generation system. In particular, given the steady technological progress in cogeneration and renewable power generation, the construction of small- or medium-sized power plants near consumer locations allows for a minimisation of electricity losses, an improved network support and an increase in efficiency of the overall electricity system. This, in turn, may result in avoiding or postponing the need for building new large power plants and/or transmission lines. These power plants closer to customers are the main elements of the well-known Distributed Generation (DG) architecture. DG expansion within the European distribution networks is however limited by technical and regulatory location-specific issues (e.g. in terms of voltage levels, network structure, availability and mix of distributed power sources, grid ownership and management). Furthermore, there are still major issues concerning the integration of DG technology into the distribution network, mainly in terms of flexibility of the generating units (production cycling) and management of the local systems (need for local power balancing resources). In fact, it has to be stressed that at the outset the distribution systems were generally not designed to operate in presence of DG technologies. The present paper investigates the current status and the forthcoming challenges related to distribution systems in Europe, with a particular attention to the technical and regulatory issues of DG integration. It examines the status of the distribution grids in some Member States and overall in the EU. This analysis of the distribution system will be matched with forecasts on DG by other studies. This comparison will yield the shortcomings and the opportunities for expanding distributed power generation.JRC.F.7-Energy systems evaluatio

La Rete di Trasmissione Europea - Infrastrutture Strategiche ed Iniziative Comunitarie

The present paper provides an update on the status of the priority projects for the expansion of the pan-European electricity system and on the European Community's initiatives supporting the development of the trans-European electricity networks.JRC.F.3-Energy securit