Optimal Allocation of Energy Storage and Wind Generation in Power Distribution Systems

The advent of energy storage technologies applications for the electric power system gives new tools for planners to cope with the operation challenges that come from the integration of renewable generation in medium voltage networks. This work proposes and implements an optimization model for Battery Energy Storage System (BESS) and distributed generation allocation in radial distribution networks. The formulation aims to assist distribution system operators in the task of making decisions on energy storage investment, BESSs\u27 operation, and distributed generation penetration\u27s level to minimize electricity costs. The BESSs are required to participate in energy arbitrage and voltage control. In addition, due to the complexity of the model formulated, a genetic algorithm combined with an AC multi-period optimal power flow implementation is used to solve the problem. The methodology provides the optimal connection points and size of a predetermined number of BESSs and wind generators, and the BESS\u27s operation. The model considers the BESSs\u27 charging/discharging efficiency, depth of discharge level, and the network\u27s operation constraints on the nodal voltage and branches power flow limits. The proposed methodology was evaluated in the IEEE 33-bus system. The results show that BESSs investment in radial distribution systems facilitates the deployment of distributed generation and favors the reduction of generation costs despite its still high capital cost. Adviser: Fred Choobine

Strategic market participation of an energy storage system in a competitive electricity market considering short-run uncertainties

This thesis proposes an efficient method for scheduling and operating a power system with a single storage unit. The method utilizes a market clearing mechanism that incorporates distributed robust chance constraint (DRCC) methods to manage the risk associated with uncertain flexible technologies. The study assumes a fully centralized market setup and aims to optimize utility within the power sector while accounting for the presence of a storage system. The approach assumes an affine response to uncertainty, enabling the market operator to identify the most effective plan for executing flexibility to maximize social welfare in the day-ahead market and manage potential power imbalances in real-time operations. The dispatch mechanism takes into account the "availability costs" of flexible assets to manage their utilization efficiently. The study demonstrates that the proposed method enhances social welfare by taking advantage of the synergies between interconnected power networks and storage, particularly in situations where renewable energy generation is uncertain. However, the model is sensitive to the choice of price differences, availability costs, and investment costs, and cannot precisely advise building an energy storage system to provide flexibility response.This thesis proposes an efficient method for scheduling and operating a power system with a single storage unit. The method utilizes a market clearing mechanism that incorporates distributed robust chance constraint (DRCC) methods to manage the risk associated with uncertain flexible technologies. The study assumes a fully centralized market setup and aims to optimize utility within the power sector while accounting for the presence of a storage system. The approach assumes an affine response to uncertainty, enabling the market operator to identify the most effective plan for executing flexibility to maximize social welfare in the day-ahead market and manage potential power imbalances in real-time operations. The dispatch mechanism takes into account the "availability costs" of flexible assets to manage their utilization efficiently. The study demonstrates that the proposed method enhances social welfare by taking advantage of the synergies between interconnected power networks and storage, particularly in situations where renewable energy generation is uncertain. However, the model is sensitive to the choice of price differences, availability costs, and investment costs, and cannot precisely advise building an energy storage system to provide flexibility response

Distributed Generation, Storage, Demand Response, and Energy Efficiency as Alternatives to Grid Capacity Enhancement

The need for investment in capital intensive electricity networks is on the rise in many countries. A major advantage of distributed resources is their potential for deferring investments in distribution network capacity. However, utilizing the full benefits of these resources requires addressing several technical, economic and regulatory challenges. A significant barrier pertains to the lack of an efficient market mechanism that enables this concept and also is consistent with business model of distribution companies under an unbundled power sector paradigm. This paper proposes a market-oriented approach termed as “contract for deferral scheme” (CDS). The scheme outlines how an economically efficient portfolio of distributed generation, storage, demand response and energy efficiency can be integrated as network resources to reduce the need for grid capacity and defer demand driven network investments

Maximising revenue for non-firm distributed wind generation with energy storage in an active management scheme

The connection of high penetrations of renewable generation such as wind to distribution networks requires new active management techniques. Curtailing distributed generation during periods of network congestion allows for a higher penetration of distributed wind to connect, however, it reduces the potential revenue from these wind turbines. Energy storage can be used to alleviate this and the store can also be used to carry out other tasks such as trading on an electricity spot market, a mode of operation known as arbitrage. The combination of available revenue streams is crucial in the financial viability of energy storage. This study presents a heuristic algorithm for the optimisation of revenue generated by an energy storage unit working with two revenue streams: generation-curtailment reduction and arbitrage. The algorithm is used to demonstrate the ability of storage to generate revenue and to reduce generation curtailment for two case study networks. Studies carried out include a single wind farm and multiple wind farms connected under a 'last-in-first-out' principle of access. The results clearly show that storage using both operating modes increases revenue over either mode individually. Moreover, energy storage is shown to be effective at reducing curtailment while increasing the utilisation of circuits linking the distribution and transmission networks. Finally, renewable subsidies are considered as a potential third revenue stream. It is interesting to note that under current market agreements such subsidies have the potential to perversely encourage the installation of inefficient storage technologies, because of increased losses facilitating greater "utilisation" of renewable generation

Scenarios for the development of smart grids in the UK: literature review

Smart grids are expected to play a central role in any transition to a low-carbon energy future, and much research is currently underway on practically every area of smart grids. However, it is evident that even basic aspects such as theoretical and operational definitions, are yet to be agreed upon and be clearly defined. Some aspects (efficient management of supply, including intermittent supply, two-way communication between the producer and user of electricity, use of IT technology to respond to and manage demand, and ensuring safe and secure electricity distribution) are more commonly accepted than others (such as smart meters) in defining what comprises a smart grid. It is clear that smart grid developments enjoy political and financial support both at UK and EU levels, and from the majority of related industries. The reasons for this vary and include the hope that smart grids will facilitate the achievement of carbon reduction targets, create new employment opportunities, and reduce costs relevant to energy generation (fewer power stations) and distribution (fewer losses and better stability). However, smart grid development depends on additional factors, beyond the energy industry. These relate to issues of public acceptability of relevant technologies and associated risks (e.g. data safety, privacy, cyber security), pricing, competition, and regulation; implying the involvement of a wide range of players such as the industry, regulators and consumers. The above constitute a complex set of variables and actors, and interactions between them. In order to best explore ways of possible deployment of smart grids, the use of scenarios is most adequate, as they can incorporate several parameters and variables into a coherent storyline. Scenarios have been previously used in the context of smart grids, but have traditionally focused on factors such as economic growth or policy evolution. Important additional socio-technical aspects of smart grids emerge from the literature review in this report and therefore need to be incorporated in our scenarios. These can be grouped into four (interlinked) main categories: supply side aspects, demand side aspects, policy and regulation, and technical aspects.

Scenarios for the development of smart grids in the UK: synthesis report

‘Smart grid’ is a catch-all term for the smart options that could transform the ways society produces, delivers and consumes energy, and potentially the way we conceive of these services. Delivering energy more intelligently will be fundamental to decarbonising the UK electricity system at least possible cost, while maintaining security and reliability of supply. Smarter energy delivery is expected to allow the integration of more low carbon technologies and to be much more cost effective than traditional methods, as well as contributing to economic growth by opening up new business and innovation opportunities. Innovating new options for energy system management could lead to cost savings of up to £10bn, even if low carbon technologies do not emerge. This saving will be much higher if UK renewable energy targets are achieved. Building on extensive expert feedback and input, this report describes four smart grid scenarios which consider how the UK’s electricity system might develop to 2050. The scenarios outline how political decisions, as well as those made in regulation, finance, technology, consumer and social behaviour, market design or response, might affect the decisions of other actors and limit or allow the availability of future options. The project aims to explore the degree of uncertainty around the current direction of the electricity system and the complex interactions of a whole host of factors that may lead to any one of a wide range of outcomes. Our addition to this discussion will help decision makers to understand the implications of possible actions and better plan for the future, whilst recognising that it may take any one of a number of forms

Distributed Resources Shift Paradigms on Power System Design, Planning, and Operation: An Application of the GAP Model

Power systems have evolved following a century-old paradigm of planning and operating a grid based on large central generation plants connected to load centers through a transmission grid and distribution lines with radial flows. This paradigm is being challenged by the development and diffusion of modular generation and storage technologies. We use a novel approach to assess the sequencing and pacing of centralized, distributed, and off-grid electrification strategies by developing and employing the grid and access planning (GAP) model. GAP is a capacity expansion model to jointly assess operation and investment in utility-scale generation, transmission, distribution, and demand-side resources. This paper conceptually studies the investment and operation decisions for a power system with and without distributed resources. Contrary to the current practice, we find hybrid systems that pair grid connections with distributed energy resources (DERs) are the preferred mode of electricity supply for greenfield expansion under conservative reductions in photovoltaic panel (PV) and energy storage prices. We also find that when distributed PV and storage are employed in power system expansion, there are savings of 15%-20% mostly in capital deferment and reduced diesel use. Results show that enhanced financing mechanisms for DER PV and storage could enable 50%-60% of additional deployment and save 15 /MWh in system costs. These results have important implications to reform current utility business models in developed power systems and to guide the development of electrification strategies in underdeveloped grids

Electricity Network Scenarios for Great Britain in 2050

The next fifty years are likely to see great developments in the technologies deployed in electricity systems, with consequent changes in the structure and operation of power networks. This paper, which forms a chapter in the forthcoming book Future Electricity Technologies and Systems, develops and presents six possible future electricity industry scenarios for Great Britain, focussed on the year 2050. The paper draws upon discussions of important technologies presented by expert authors in other chapters of the book to consider the impact of different combinations of key influences on the nature of the power system in 2050. For each scenario there is a discussion of the effects of the key parameters, with a description and pictorial illustration. Summary tables identify the role of the technologies presented in other chapters of the book, and list important figures of interest, such as the capacity and energy production of renewable generation technologies

Energy storage in the UK electrical network : estimation of the scale and review of technology options

This paper aims to clarify the difference between stores of energy in the form of non-rechargeable stores of energy such as fossil-fuels, and the storage of electricity by devices that are rechargeable. The existing scale of these two distinct types of storage is considered in the UK context, followed by a review of rechargeable technology options. The storage is found to be overwhelmingly contained within the fossil-fuel stores of conventional generators, but their scale is thought to be determined by the risks associated with long supply chains and price variability. The paper also aims to add to the debate regarding the need to have more flexible supply and demand available within the UK electrical network in order to balance the expected increase of wind derived generation. We conclude that the decarbonisation challenge facing the UK electricity sector should be seen not only as a supply and demand challenge but also as a storage challenge. (c) 2010 Elsevier Ltd. All rights reserved

Green revolution 2.0: a sustainable energy path

This repository item contains a single issue of Sustainable Development Insights, a series of short policy essays that began publishing in 2008 by the Boston University Frederick S. Pardee Center for the Study of the Longer-Range Future. The series seeks to promote a broad interdisciplinary dialogue on how to accelerate sustainable development at all levels.The Green Revolution in agriculture greatly increased crop yields and averted mass starvation, but it also turned small farms into factory farms that concentrated production in a few locations and reduced the diversity of crops. In this paper, Professor Nalin Kulatilaka, Co-Director of BU’s Clean Energy & Environmental Sustainability Initiative, calls for a Green Energy Revolution that decentralizes energy supplies through a smart electricity network. He argues that such a revolution could provide for a diversity of energy sources located closer to users, which in turn could shift consumption patterns, reduce losses and decrease overall energy demand. He concludes that shifting to such a system “will adopt clean energy technologies while fostering new businesses, creating new jobs and ultimately empowering society to reach new heights in energy conservation and sustainability“