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Direct current distribution systems (DCDS) are a promising alternative to alternating current (AC) systems because they remove AC--DC conversion between sources and loads that cause energy losses. Compared to AC systems, a DCDS has higher power capacity, energy efficiency and reliability, and no need for synchronisation---suitable where a large amount of renewable power is generated and consumed locally in DC. A DCDS has unique features that affect its implementation: low system inertia, strict power limits and power--voltage coupling. Hence, simply applying markets designed for AC cannot guarantee a DCDS's supply security and voltage stability. This dissertation aims to identify DC-tailored local market designs that facilitate a DCDS's operational efficiency and reliability under uncertainty. To identify promising DCDS market designs from all feasible options, we developed and applied a comprehensive design framework for local electricity markets. It is based on an engineering design process of identifying goals, determining design space, testing and evaluation. Whereas previous studies focused on individual commodities, we widened the scope to include the role of market architecture. Its main element is the choice of sub-markets for energy delivery, the provision of DC-substation capacity, and voltage regulation. For each selected sub-market, we analysed the design options for the general organisation, bid format, allocation and payment, and settlement. Considering the design complexity, we performed three rounds of market design according to the agile development principle: a qualitative assessment, a quantitative analysis without uncertainty, and a quantitative analysis under uncertainty. In Step 1, we analysed the design options and identified three types of DCDS market designs according to the above framework, each featuring a unique architecture. First, the integrated market (IM) design explicitly links three sub-markets (for energ, Energy & Industry

Direct current distribution systems (DCDS) are a promising alternative to alternating current (AC) systems because they remove AC--DC conversion between sources and loads that cause energy losses. Compared to AC systems, a DCDS has higher power capacity, energy efficiency and reliability, and no need for synchronisation---suitable where a large amount of renewable power is generated and consumed locally in DC. A DCDS has unique features that affect its implementation: low system inertia, strict power limits and power--voltage coupling. Hence, simply applying markets designed for AC cannot guarantee a DCDS's supply security and voltage stability. This dissertation aims to identify DC-tailored local market designs that facilitate a DCDS's operational efficiency and reliability under uncertainty. To identify promising DCDS market designs from all feasible options, we developed and applied a comprehensive design framework for local electricity markets. It is based on an engineering design process of identifying goals, determining design space, testing and evaluation. Whereas previous studies focused on individual commodities, we widened the scope to include the role of market architecture. Its main element is the choice of sub-markets for energy delivery, the provision of DC-substation capacity, and voltage regulation. For each selected sub-market, we analysed the design options for the general organisation, bid format, allocation and payment, and settlement. Considering the design complexity, we performed three rounds of market design according to the agile development principle: a qualitative assessment, a quantitative analysis without uncertainty, and a quantitative analysis under uncertainty. In Step 1, we analysed the design options and identified three types of DCDS market designs according to the above framework, each featuring a unique architecture. First, the integrated market (IM) design explicitly links three sub-markets (for energ, Energie and Industrie

DC distribution systems are a promising alternative to existing AC distribution systems. They connect customers to local energy sources without conversion, thus reducing power losses. However, the unique features of DC impose strict requirements for system operation compared to AC. Within the context of a liberalized energy market, this article demonstrates three promising market designs—an outcome of a comprehensive engineering design framework—that meet those DC requirements. They are an integrated market design, which incorporates all system costs into energy prices; a market design that passes wholesale energy prices directly to prosumers; and a locational energy market design that relieves congestion with nodal prices. An optimization model estimates the three market designs’ performance by simulating a realistic DC distribution system, featuring a high share of electric vehicles. Results indicate that the integrated market design is optimal in theory but computationally infeasible in practice. The wholesale energy price design aiming at constraint-free energy trading requires substantial investments in flexibility. The locational energy market design yields nearly optimal operation in urban networks and is considered the best feasible market design for DC distribution systems., Algorithmics, Energy & Industry

DC distribution systems are a promising alternative to existing AC distribution systems. They connect customers to local energy sources without conversion, thus reducing power losses. However, the unique features of DC impose strict requirements for system operation compared to AC. Within the context of a liberalized energy market, this article demonstrates three promising market designs—an outcome of a comprehensive engineering design framework—that meet those DC requirements. They are an integrated market design, which incorporates all system costs into energy prices; a market design that passes wholesale energy prices directly to prosumers; and a locational energy market design that relieves congestion with nodal prices. An optimization model estimates the three market designs’ performance by simulating a realistic DC distribution system, featuring a high share of electric vehicles. Results indicate that the integrated market design is optimal in theory but computationally infeasible in practice. The wholesale energy price design aiming at constraint-free energy trading requires substantial investments in flexibility. The locational energy market design yields nearly optimal operation in urban networks and is considered the best feasible market design for DC distribution systems., Algorithmics, Energie and Industrie

Direct Current Distribution System (DCDS), a promising alternative to existing AC systems, connect customers to DC energy sources without AC/DC conversion. The unique features of DC, including the power-voltage coupling effect, impose different requirements to DCDS operation compared to AC. Addressing a liberalized energy market, this paper investigates the significant impact of market design on DCDS operation with an empirical analysis of electric vehicle charging. With an empirical analysis on EV charging, we investigate the level of efficiency a centralized market may theoretically reach, then compare it with a market based on prosumers’ local decision., Algorithmics, Energy & Industry

DC distribution systems (DCDSs) are a promising alternative to AC systems because they remove AC-DC conversions between renewable sources and loads. Their unique features compared to AC include low system inertia, strict power limits and power–voltage coupling. In a liberalised electricity market, merely applying an AC market design to a DCDS cannot guarantee the latter’s supply security and voltage stability; new markets must be designed to meet DC challenges. This article identifies the key design options of DCDS electricity markets. To identify these options, we develop a comprehensive design framework for local electricity markets; to our knowledge, we provide the first such analysis. Whereas previous studies focus on separate aspects of DCDS markets, we widen the scope to include the role of market architecture and investigate the arrangements of sub-markets. As an illustration, we demonstrate three promising DCDS market designs that can be defined in our framework, and provide a first assessment of their performance., Algorithmics, Energy & Industry

Direct Current Distribution System (DCDS), a promising alternative to existing AC systems, connect customers to DC energy sources without AC/DC conversion. The unique features of DC, including the power-voltage coupling effect, impose different requirements to DCDS operation compared to AC. Addressing a liberalized energy market, this paper investigates the significant impact of market design on DCDS operation with an empirical analysis of electric vehicle charging. With an empirical analysis on EV charging, we investigate the level of efficiency a centralized market may theoretically reach, then compare it with a market based on prosumers’ local decision., Algorithmics, Energie and Industrie

DC distribution systems (DCDSs) are a promising alternative to AC systems because they remove AC-DC conversions between renewable sources and loads. Their unique features compared to AC include low system inertia, strict power limits and power–voltage coupling. In a liberalised electricity market, merely applying an AC market design to a DCDS cannot guarantee the latter’s supply security and voltage stability; new markets must be designed to meet DC challenges. This article identifies the key design options of DCDS electricity markets. To identify these options, we develop a comprehensive design framework for local electricity markets; to our knowledge, we provide the first such analysis. Whereas previous studies focus on separate aspects of DCDS markets, we widen the scope to include the role of market architecture and investigate the arrangements of sub-markets. As an illustration, we demonstrate three promising DCDS market designs that can be defined in our framework, and provide a first assessment of their performance., Algorithmics, Energie and Industrie

Direct current distribution systems (DCDS), which connect local prosumers directly to community grids without AC/DC conversions, are a promising alternative to AC systems. While regulations call for market-based operation, existing markets for AC systems do not meet DC requirements and cannot be applied to a DCDS. This paper develops a design framework for local electricity markets and with it explores possible DCDS market designs. We review the technical requirements and desired properties for DCDS operation, enumerate its market design goals, then identify the design variables influencing the short-term market efficiency. This paper is our first step towards a systematic DCDS market design, and it supports our future work on quantitative analysis of the design choices., Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., Algorithmics, Energy & Industry

Under the background of global energy conservation, the energy hub (EH)-based integrated energy system is becoming the transition direction of future energy structure. In this paper, we study the cooperative economic scheduling problem for multiple neighboring integrated energy systems on the basis of EH. Different with the traditional non-cooperative mode where each EH operates individually, these EHs constitute a cooperative community and can share energy among them. Considering the autonomy and selfinterest of different EHs, the coordinated management problem is modeled as a bargaining cooperative game, where involved EHs will bargain with each other about the exchanged energy and the associated payments. The bargaining solution can achieve a fair and Pareto-optimal balance among the objective functions of different EHs. A distributed optimization is applied to find the bargaining solution of the cooperative system, to guarantee the autonomous scheduling and information privacy of EHs. Numerical studies demonstrate the effectiveness of the bargaining-based cooperative economic scheduling framework, and also show the improvement of benefits of the community system., Algorithmics

Battery energy storage (BES) and demand response (DR) are considered to be promising technologies to cope with the uncertainty of renewable energy sources (RES) and the load in the microgrid (MG). Considering the distinct prediction accuracies of the RES and load at different timescales, it is essential to incorporate the multi-timescale characteristics of BES and DR in MG energy management. Under this background, a hierarchical energy management framework is put forward for an MG including multi-timescale BES and DR to optimize operation with the uncertainty of RES as well as load. This framework comprises three stages of scheduling: day-ahead scheduling (DAS), hour-ahead scheduling (HAS), and real-time scheduling (RTS). In DAS, a scenario-based stochastic optimization model is established to minimize the expected operating cost of MG, while ensuring its safe operation. The HAS is utilized to bridge DAS and RTS. In RTS, a control strategy is proposed to eliminate the imbalanced power owing to the fluctuations of RES and load. Then, a decomposition-based algorithm is adopted to settle the models in DAS and HAS. Simulation results on a seven-bus MG validate the effectiveness of the proposed methodology., Algorithmics

Direct current distribution systems (DCDS), which connect local prosumers directly to community grids without AC/DC conversions, are a promising alternative to AC systems. While regulations call for market-based operation, existing markets for AC systems do not meet DC requirements and cannot be applied to a DCDS. This paper develops a design framework for local electricity markets and with it explores possible DCDS market designs. We review the technical requirements and desired properties for DCDS operation, enumerate its market design goals, then identify the design variables influencing the short-term market efficiency. This paper is our first step towards a systematic DCDS market design, and it supports our future work on quantitative analysis of the design choices., Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., Algorithmics, Energie and Industrie

Battery energy storage (BES) and demand response (DR) are considered to be promising technologies to cope with the uncertainty of renewable energy sources (RES) and the load in the microgrid (MG). Considering the distinct prediction accuracies of the RES and load at different timescales, it is essential to incorporate the multi-timescale characteristics of BES and DR in MG energy management. Under this background, a hierarchical energy management framework is put forward for an MG including multi-timescale BES and DR to optimize operation with the uncertainty of RES as well as load. This framework comprises three stages of scheduling: day-ahead scheduling (DAS), hour-ahead scheduling (HAS), and real-time scheduling (RTS). In DAS, a scenario-based stochastic optimization model is established to minimize the expected operating cost of MG, while ensuring its safe operation. The HAS is utilized to bridge DAS and RTS. In RTS, a control strategy is proposed to eliminate the imbalanced power owing to the fluctuations of RES and load. Then, a decomposition-based algorithm is adopted to settle the models in DAS and HAS. Simulation results on a seven-bus MG validate the effectiveness of the proposed methodology., Algorithmics

Under the background of global energy conservation, the energy hub (EH)-based integrated energy system is becoming the transition direction of future energy structure. In this paper, we study the cooperative economic scheduling problem for multiple neighboring integrated energy systems on the basis of EH. Different with the traditional non-cooperative mode where each EH operates individually, these EHs constitute a cooperative community and can share energy among them. Considering the autonomy and selfinterest of different EHs, the coordinated management problem is modeled as a bargaining cooperative game, where involved EHs will bargain with each other about the exchanged energy and the associated payments. The bargaining solution can achieve a fair and Pareto-optimal balance among the objective functions of different EHs. A distributed optimization is applied to find the bargaining solution of the cooperative system, to guarantee the autonomous scheduling and information privacy of EHs. Numerical studies demonstrate the effectiveness of the bargaining-based cooperative economic scheduling framework, and also show the improvement of benefits of the community system., Algorithmics

DC distribution systems (DCDS) connect local generators and loads directly. By avoiding unnecessary losses in AC-DC conversion, DCDS offers higher energy efficiency. Since different parties in a DCDS may have conflicting goals, matching between power supply and demand should be done with carefully designed allocation rules and monetary transfers, such that no one prefers to act otherwise than the outcome of the allocation. This paper reveals DCDS' unique operational requirements and indicates the challenges and opportunities they pose to market design. A design framework is introduced into DCDS electricity market, incl. tradable services, design goals, market participants, design options and performance criteria. We review the existing market models for AC and DC distribution systems and point out the direction for future work., Algorithmics, Energy & Industry

DC distribution systems (DCDS) connect local generators and loads directly. By avoiding unnecessary losses in AC-DC conversion, DCDS offers higher energy efficiency. Since different parties in a DCDS may have conflicting goals, matching between power supply and demand should be done with carefully designed allocation rules and monetary transfers, such that no one prefers to act otherwise than the outcome of the allocation. This paper reveals DCDS' unique operational requirements and indicates the challenges and opportunities they pose to market design. A design framework is introduced into DCDS electricity market, incl. tradable services, design goals, market participants, design options and performance criteria. We review the existing market models for AC and DC distribution systems and point out the direction for future work., Algorithmics, Energie and Industrie