1,319 research outputs found
Review of trends and targets of complex systems for power system optimization
Optimization systems (OSs) allow operators of electrical power systems (PS) to optimally operate PSs and to also create optimal PS development plans. The inclusion of OSs in the PS is a big trend nowadays, and the demand for PS optimization tools and PS-OSs experts is growing. The aim of this review is to define the current dynamics and trends in PS optimization research and to present several papers that clearly and comprehensively describe PS OSs with characteristics corresponding to the identified current main trends in this research area. The current dynamics and trends of the research area were defined on the basis of the results of an analysis of the database of 255 PS-OS-presenting papers published from December 2015 to July 2019. Eleven main characteristics of the current PS OSs were identified. The results of the statistical analyses give four characteristics of PS OSs which are currently the most frequently presented in research papers: OSs for minimizing the price of electricity/OSs reducing PS operation costs, OSs for optimizing the operation of renewable energy sources, OSs for regulating the power consumption during the optimization process, and OSs for regulating the energy storage systems operation during the optimization process. Finally, individual identified characteristics of the current PS OSs are briefly described. In the analysis, all PS OSs presented in the observed time period were analyzed regardless of the part of the PS for which the operation was optimized by the PS OS, the voltage level of the optimized PS part, or the optimization goal of the PS OS.Web of Science135art. no. 107
A Comprehensive Method For Coordinating Distributed Energy Resources In A Power Distribution System
Utilities, faced with increasingly limited resources, strive to maintain high levels of reliability in energy delivery by adopting improved methodologies in planning, operation, construction and maintenance. On the other hand, driven by steady research and development and increase in sales volume, the cost of deploying PV systems has been in constant decline since their first introduction to the market. The increased level of penetration of distributed energy resources in power distribution infrastructure presents various benefits such as loss reduction, resilience against cascading failures and access to more diversified resources. However, serious challenges and risks must be addressed to ensure continuity and reliability of service. By integrating necessary communication and control infrastructure into the distribution system, to develop a practically coordinated system of distributed resources, controllable load/generation centers will be developed which provide substantial flexibility for the operation of the distribution system. On the other hand, such a complex distributed system is prone to instability and black outs due to lack of a major infinite supply and other unpredicted variations in load and generation, which must be addressed. To devise a comprehensive method for coordination between Distributed Energy Resources in order to achieve a collective goal, is the key point to provide a fully functional and reliable power distribution system incorporating distributed energy resources. A road map to develop such comprehensive coordination system is explained and supporting scenarios and their associated simulation results are then elaborated. The proposed road map describes necessary steps to build a comprehensive solution for coordination between multiple agents in a microgrid or distribution feeder.\u2
Electric vehicle energy integration scenarios: a feasibility analysis environment
The UK Government has set a goal that by 2040, every new car will be an ultra-low emission vehicle. This makes the exploitation of excess storage in electric vehicles to provide electricity support potentially beneficial. The technology required to utilise this opportunity is called ‘vehicle-to-grid’, primarily a vehicle connection post with a built-in bi-directional inverter, providing both vehicle charging and discharging functionality. Through utilisation of this equipment, local energy systems, such as building clusters, can utilise the excess energy stored within the vehicles parked on site.
The aim of this research was to create a platform from which to evaluate the investment opportunity of vehicle-to-grid in a local services case study for future energy scenarios. As such, a feasibility analysis environment was developed that evaluates the economic benefit to both vehicle and building owners in installing vehicle-to-grid. The software has the capability to assess any case study with a collection of buildings, vehicles, photovoltaics or market demand. Energy scenarios have been developed within the software to run case studies for economic evaluation, with the scenarios ranging from building peak shaving, tariff demand reduction, photovoltaic demand shifting and energy market provision. By altering the number of vehicles being assessed, the software can also calculate infrastructure provision requirements and related costs. [Continues.
Optimal Management of an Integrated Electric Vehicle Charging Station under Weather Impacts
The focus of this Dissertation is on developing an optimal management of what is
called the “Integrated Electric Vehicle Charging Station” (IEVCS) comprising the
charging stations for the Plug-in Electric Vehicles (PEVs), renewable (solar) power
generation resources, and fixed battery energy storage in the buildings. The reliability and
availability of the electricity supply caused by severe weather elements are affecting utility
customers with such integrated facilities. The proposed management approach allows such
a facility to be coordinated to mitigate the potential impact of weather condition on
customers electricity supply, and to provide warnings for the customers and utilities to
prepare for the potential electricity supply loss. The risk assessment framework can be
used to estimate and mitigate such impacts.
With proper control of photovoltaic (PV) generation, PEVs with mobile battery
storage and fixed energy storage, customers’ electricity demand could be potentially more
flexible, since they can choose to charge the vehicles when the grid load demand is light,
and stop charging or even supply energy back to the grid or buildings when the grid load
demand is high. The PV generation capacity can be used to charge the PEVs, fixed battery
energy storage system (BESS) or supply power to the grid. Such increased demand
flexibility can enable the demand response providers with more options to respond to
electricity price changes. The charging stations integration and interfacing can be
optimized to minimize the operational cost or support several utility applications
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Challenges to the Integration of Renewable Resources at High System Penetration
Successfully integrating renewable resources into the electric grid at penetration levels to meet a 33 percent Renewables Portfolio Standard for California presents diverse technical and organizational challenges. This report characterizes these challenges by coordinating problems in time and space, balancing electric power on a range of scales from microseconds to decades and from individual homes to hundreds of miles. Crucial research needs were identified related to grid operation, standards and procedures, system design and analysis, and incentives, and public engagement in each scale of analysis. Performing this coordination on more refined scales of time and space independent of any particular technology, is defined as a “smart grid.” “Smart” coordination of the grid should mitigate technical difficulties associated with intermittent and distributed generation, support grid stability and reliability, and maximize benefits to California ratepayers by using the most economic technologies, design and operating approaches
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Grid flexibility by electrifying energy systems for sustainable aviation
This thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University LondonDecarbonisation of aviation goals set by Flightpath 2050 Europe’s Vision for Aviation
requires that the airports become emission-free by 2050. This thesis original contribution to
knowledge is to explore the incorporation of aviation electrification technologies, including
electric aircraft (EA), electrified ground support equipment (GSE), and airport parking electric
vehicles (EVs), into power systems, evaluating their influence on grid infrastructure and
operations, as well as their potential to support the grid operation.
A comprehensive review of aviation electrification technologies revealed a research gap in the
integration of these technologies into the power systems. The thesis contributes to electricity
network infrastructure planning for electrification of aviation and airport-based distributed
energy resources (DER) that provide ancillary services to the power grid.
A multi-objective airport microgrid planning framework is developed, comparing EA charging
strategies and revealing that battery swap performs better. Vehicle-to-grid (V2G) strategy with
parking EVs improves the microgrid's performance. A techno-economic assessment of wireless charging
systems for electric airport shuttle buses shows better economic performance than conventional
buses and other charging options.
A novel Aviation-to-Grid (A2G) flexibility concept provides frequency response services to the GB
power system using EA battery charging systems, with typical A2G service capacity showing
significant variation across eight UK airports. A deep reinforcement learning (DRL)-based A2G
dispatch approach evaluates the impact of EA charger capacity on energy dispatch results, with
higher capacities leading to higher revenue and lower operation costs.
To summarise, this thesis addresses the research gaps in integrating aviation
electrification technologies into power systems, offering valuable insights for airport operators
aiming to decarbonise air transport activities through the adoption of these technologies. The
study also provides an understanding of the impacts on grid operators in terms of infrastructure
planning and operations. This comprehensive approach ensures a cohesive understanding of the
challenges and opportunities presented by aviation
electrification and its integration into power systems
Energy storage and electric vehicles as a means of mitigating uncertainty in urban microgrids
Phd ThesisThe United Kingdom (UK) government intends to end the sale of new conventional petrol
and diesel cars by 2040, and Electric Vehicles (EVs) could emerge as the replacement. This
is likely to increase the load on electrical distribution networks, while uncontrolled EV
charging could increase load forecast uncertainty. Utilising sufficient Energy Storage System
(ESS) power to maintain the networks within their power flow and voltage limits without
needing to reinforce the network, while not over using the storage despite the uncertainty,
remains a challenge. Similarly, the EVs themselves have been suggested as a flexible load
however realising this flexibility also remains a challenge. This Thesis researches the ability
of ESSs and EVs to mitigate load and generation uncertainty within urban microgrids.
Initially, the technical and economic impacts of uncontrolled EV charging on distribution
networks is investigated by combining an extensive real world dataset of EV charging events
and domestic household load. It is found that distribution transformer power flow limits will
be the first operational limit to be breached when EV penetration reaches 40%. The resulting
reinforcement cost that Ofgem would allow Distribution Network Operators (DNOs) to
recover from consumers is estimated at £60.81bn - £74.27bn up to 2040.
A methodology is then proposed to forecast future uncontrolled EV charging load based on
the ‘here and now’ load experienced on the network. In addition, a methodology is proposed
to aggregate a number of smart charging EVs to form a Virtual Energy Storage System
(VESS) able to deliver services to the distribution network with a high degree of
controllability (~99%), while also guaranteeing the energy required by the EVs for their
primary purpose of transportation. The VESS is combined with other forms of flexibility to
deliver an Enhanced Frequency Response (EFR) service where a fuzzy logic control
methodology is proposed to maximise power availability.
Finally, a Robust Optimisation (RO) formulation is developed that balances the trade-off
between the cost of protecting network operational limits from load and generation
uncertainty, against the cost of failing to protect network operational limits. RO requires a
linear representation of the power system, and the errors introduced through linearization via
sensitivity factors are calculated as up to 1.6% when there is no load and generation
uncertainty, and up to 4.0% when there is load and generation uncertainty.Engineering and Physical Sciences Research Council (EPSRC)
Siemen
Smart Metering Technology and Services
Global energy context has become more and more complex in the last decades; the raising prices of fuels together with economic crisis, new international environmental and energy policies that are forcing companies. Nowadays, as we approach the problem of global warming and climate changes, smart metering technology has an effective use and is crucial for reaching the 2020 energy efficiency and renewable energy targets as a future for smart grids. The environmental targets are modifying the shape of the electricity sectors in the next century. The smart technologies and demand side management are the key features of the future of the electricity sectors. The target challenges are coupling the innovative smart metering services with the smart meters technologies, and the consumers' behaviour should interact with new technologies and polices. The book looks for the future of the electricity demand and the challenges posed by climate changes by using the smart meters technologies and smart meters services. The book is written by leaders from academia and industry experts who are handling the smart meters technologies, infrastructure, protocols, economics, policies and regulations. It provides a promising aspect of the future of the electricity demand. This book is intended for academics and engineers who are working in universities, research institutes, utilities and industry sectors wishing to enhance their idea and get new information about the smart meters
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