62 research outputs found
From pan-continental to inter-continental systems analyses: Planning HVDC corridors in long-term grid studies
No full textThis paper, after providing an overview on key past and ongoing continental studies, with particular focus on European and neighboring regions, presents a methodological approach for an optimal long-term development of an intercontinental grid based on HVDC corridors
Modeling of a smart grid system using real time data on NEPLAN
No full textThe simulation model of the Smart Grids Laboratory of the Institute of Energy and Transport is presented in this paper and a day of its operation is analyzed. The developed model simulates six different modules (a photovoltaic array, a Li-ion battery storage system, a small wind turbine, a diesel generator, a laboratory load and the connection point with the grid). The modules are connected radially at a common bus
Modeling a large-scale battery energy storage system for power grid application analysis
No full textThe interest in modeling the operation of large-scale battery energy storage systems (BESS) for analyzing power grid applications is rising. This is due to the increasing storage capacity installed in power systems for providing ancillary services and supporting nonprogrammable renewable energy sources (RES). BESS numerical models suitable for grid-connected applications must offer a trade-off, keeping a high accuracy even with limited computational effort. Moreover, they are asked to be viable in modeling for real-life equipment, and not just accurate in the simulation of the electrochemical section. The aim of this study is to develop a numerical model for the analysis of the grid-connected BESS operation; the main goal of the proposal is to have a test protocol based on standard equipment and just based on charge/discharge tests, i.e., a procedure viable for a BESS owner without theoretical skills in electrochemistry or lab procedures, and not requiring the ability to disassemble the BESS in order to test each individual component. The BESS model developed is characterized by an experimental campaign. The test procedure itself is framed in the context of this study and adopted for the experimental campaign on a commercial large-scale BESS. Once the model is characterized by the experimental parameters, it undergoes the verification and validation process by testing its accuracy in simulating the provision of frequency regulation. A case study is presented for the sake of presenting a potential application of the model. The procedure developed and validated is replicable in any other facility, due to the low complexity of the proposed experimental set. This could help stakeholders to accurately simulate several layouts of network services
The Impact of Large Renewable Deployment on Electricity High Voltage Systems
No full textIn the last decades an increasing integration of renewable energy sources (RES) in the extra high voltage (EHV) and high voltage (HV) networks, boosted by technical reasons and political decisions has been noticed. RES introduce significant environmental benefits, but also considerable difficulties to power system planning and operation. In fact, if RES are correctly allocated, they allow deferring network upgrade investments and decreasing Joule losses. On the other hand, the uncertainty of RES production may cause dispatching problems, malfunctioning of protection and voltage regulation systems, etc. Many European Union (EU) research projects concluded that RES might be useful to accomplish economic, environmental and reliability targets removing the existing barriers to innovation and liberalized market.
The paper is part of a Research Project financed by the European Commission2
to study the influence of a large penetration of RES on the EHV and HV electrical grids. The case study proposed in the paper refers to a portion of the Italian grid, the Sardinian power system, interconnected to the Italian mainland by means of the existing 200 kV and 500 kV high voltage direct current (HVDC) submarine cables (SA.CO.I. and SA.PE.I). Sardinia is one of the most favorable Italian regions for the exploitation of wind and solar energy and it has been experiencing a great increment of wind power production, which will be doubled in the next ten years. In the paper, the models to predict at 2020 and 2030 the generation park, demand profiles, as well as the development of the electricity infrastructures in Sardinia are briefly described. The steady-state analysis of the Sardinian grid with AC Power Flow studies applied to the foreseen load and generation scenarios in 2020 and 2030 allowed identifying critical conditions of the grid caused by RES production, load profile, and the lack of homotheticity between generation and load
Distributing load flow computations across system operators boundaries using the Newton–Krylov–Schwarz algorithm implemented in PETSC
No full textThe upward trends in renewable energy penetration, cross-border flow volatility and electricity actors’ proliferation pose new challenges in the power system management. Electricity and market operators need to increase collaboration, also in terms of more frequent and detailed system analyses, so as to ensure adequate levels of quality and security of supply. This work proposes a novel distributed load flow solver enabling for better cross border flow analysis and fulfilling possible data ownership and confidentiality arrangements in place among the actors. The model exploits an Inexact Newton Method, the Newton–Krylov–Schwarz method, available in the portable, extensible toolkit for scientific computation (PETSc) libraries. A case-study illustrates a real application of the model for the TSO–TSO (transmission system operator) cross-border operation, analyzing the specific policy context and proposing a test case for a coordinated power flow simulation. The results show the feasibility of performing the distributed calculation remotely, keeping the overall simulation times only a few times slower than locally
A European Supergrid for Renewable Energy - Local Impacts and Far-reaching Challenges
No full textThis article assesses the impact of extensive deployment of indigenous and external renewable energy sources on a local electricity system (Sardinia Island) and discusses the main challenges faced by the European power grids in integrating high shares of renewable-based generation technologies. It presents the 2030 scenarios for the Sardinian power system and the results of steady-state analyses in extreme (renewable) generation and consumption conditions. These results are eventually combined with the assessment of key technology development trends to explain how this can affect the development of a European supergrid. In general, the article stresses that rendering the bulk-power system capable of accommodating high renewable energy penetration not only requires reinforcing the electricity highways
but also demands carefully planning the architecture of and the interface with regional power systems.JRC.F.7 - Energy systems evaluatio
Characterisation of electrical energy storage technologies
No full textIn the current situation with the unprecedented deployment of clean technologies for electricity generation, it is natural to expect that storage will play an important role in electricity networks. This paper provides a qualitative methodology to select the appropriate technology or mix of technologies for different applications. The multiple comparisons according to different characteristics distinguish this paper from others about energy storage systems.
Firstly, the different technologies available for energy storage, as discussed in the literature, are described and compared. The characteristics of the technologies are explained, including their current availability. In order to gain a better perspective, availability is cross-compared with maturity level. Moreover, information such as ratings, energy density, durability and costs is provided in table and graphic format for a straightforward comparison. Additionally, the different electric grid applications of energy storage technologies are described and categorised. For each of the categories, we describe the available technologies, both mature and potential. Finally, methods for connecting storage technologies are discussed
ANALYSIS AND VISUALIZATION OF NATURAL THREATS AGAINST THE SECURITY OF ELECTRICITY TRANSMISSION SYSTEM
No full textElectricity is one of the crucial energies of modern society, but it is greatly threatened by various kinds of menaces, especially natural hazards. Although they rarely happen, their occurrence may hugely affect the operation of power system. In this paper, we firstly, according the impact on power systems, classify natural threats into two categories (natural disasters and extreme weather conditions) and several subcategories (geological, hydrological, meteorological and climatological). Then the changes in natural threats to power systems and their trends during recent decades are discussed, along with a review of events that pose natural threats to the power system. Finally, the georeferenced model based on the Italy transmission system for natural threats analysis is presented
Effects of North-African electricity import on the European and the Italian power systems: a techno-economic analysis
No full textElectricity independence of the Baltic States: Present and future perspectives
No full textDue to historical and geographical reasons, the Baltic States are strongly interconnected to power transmission grids of Russia and Belarus. Current energy security policies and electricity interconnection targets in the EU trigger the need for studying and implementing alternative electricity supply options and power system configuration schemes for the Baltic countries.
In order to provide a supporting analysis for the energy policy making, with a special focus on electricity, a framework with methodologies is proposed in this paper to assess the electricity independence of the Baltic States. To comprehensively assess the electricity independence, we provided three indices: “adequacy”, “security” and “economic factor”. The proposed framework and methodologies are applied for assessing the electricity independence of the Baltic States in the present (2014) and future scenarios: mid-term (2020), and long-term (2030) time frame.
The analysis results show that the planned generation capacities are adequate to cover future electricity demand in the Baltic States in 2020 and 2030. Under the current electricity grid planning, power distribution in some local areas is limited in the future scenarios. Additional grid investments are necessary to keep high security level of power supply in 2020/30
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