Optimal EV Charge Scheduling Considering FCR Participation and Battery Degradation

Emerging vehicle-to-grid (V2G) technology gives more flexibility to electric vehicles (EVs) for participating in ancillary service markets. This paper presents an optimal charge scheduling model for EVs by considering V2G, frequency containment reserve (FCR), and battery degradation, to investigate the profitability of FCR participation for an individual EV. The model considers the EV owners’ preferences for desired energy at the departure times while participating in FCR. The total scheduling cost of the EV is minimized through a mixed integer linear programming (MILP) problem. The outputs of theMILP model are the EV’s charge/discharge pattern and the amount of power for each scheduling horizon. It is found that FCR participation is quite profitable for EV owners

A novel energy management system for optimal energy and flexibility scheduling of residential buildings: a case study in HSB Living Lab

The future distribution system needs more flexibility to handle the peak power demand arising from the electrification of heating and transportation. This paper proposes a novel energy management system (EMS) for residential buildings to optimize their electric and heat consumptions while offering flexibility in response to the requirements of the Distribution System Operator (DSO). The aim of the proposed EMS is to minimize the energy and peak power costs while simultaneously maximizing the revenue from offering flexibility. This is achieved through the optimal scheduling of battery energy storage charging and discharging as well as the efficient utilization of the heat pump. To cope with forecasting uncertainties, a rolling horizon-based algorithm with uncertainty modelling based on the chance constraint method is incorporated. The performance of the proposed EMS is investigated by simulating the daily operation of a real residential building. The case studies indicate that the scheduled flexibility can be successfully dispatched even in the presence of forecasting uncertainties, causing 6% reduction in the payment cost of the building

Stochastic Operation Scheduling Model for a Swedish Prosumer with PV and BESS in Nordic Day-Ahead Electricity Market

In this paper, an optimal stochastic operation\ua0scheduling model is proposed for a prosumer owning\ua0photovoltaic (PV) facility coupled with a Battery Energy\ua0Storage System (BESS). The objective of the model is to\ua0maximize the prosumer’s expected profits. A two-stage\ua0stochastic mixed-integer nonlinear optimization (SMINLP)\ua0approach is used to cope with the parameters’ uncertainties.\ua0Artificial Neural Networks (ANN) are used to forecast themarkets’ prices and the standard scenario reduction\ua0algorithms are applied to handle the computational\ua0tractability of the problem. The model is applied to a case\ua0study using data from the Nordic electricity markets and\ua0historical PV production data from the Chalmers University\ua0of Technology campus, considering a scaled up 5MWp power\ua0capacity. The results show that the proposed approach could\ua0increase the revenue for the prosumer by up to 11.6% as\ua0compared to the case without any strategy. Furthermore, the\ua0sensitivity analysis of BESS’s size on the expected profit shows\ua0that increasing BESS size could lead to an increase in the net\ua0profits

Congestion Management using Local Flexibility Markets: Recent Development and Challenges

Increasing amount of renewable based distributed generation at distribution systems, leads to an increased need for active distribution network management dealing with local network congestion and voltage issues. Development of local flexibility markets aims to provide a market-based solution to these issues. This paper presents a comprehensive review of proposed approaches towards markets exploiting the flexibilities from the demand-side. Efforts have been made on presenting a systematic overview of market design, including e.g. framework, participation, bidding and clearing mechanisms, of local flexibility market proposals developed in recent years. The implementation and regulatory issues and challenges are also discussed. The paper also presents the conceptual framework of the local flexibility service market which is currently being developed within UNITED-GRID project. This proposal aims to provide a holistic approach on local service markets, so that Distribution System Operators (DSOs) are provided with a market-based instrument to manage their networks efficiently

A Congestion Forecast Framework for Distribution Systems with High Penetration of PV and PEVs

This paper presents a congestion forecast framework for electrical distribution systems with high penetration of solar photovoltaic and plug-in electric vehicles. The framework is based on probabilistic power flow to account for the uncertainties in photovoltaic production and load demand. The proposed framework has been implemented and tested using the data of the real distribution grid of Chalmers University of Technology campus. Cases studies have been carried out using the framework to analyse the impact of different local production levels and operating modes of solar photovoltaic inverter. The results have shown that cumulative probability for network congestion in branches and transformers would increase by 30% and 20% respectively, when the level of local PV generation, demand and PEVs demand to increase by 100%, 95% and 100% respectively. Also, results have shown that network congestion in branches and transformers is 4% and 8% respectively, more likely to occur in the constant-V mode as compared to constant-pf mode. These results can help distribution system operators to predict any upcoming congestion in their system and subsequently help them in taking suitable actions in order to mitigate congestion

Inflamed Non-Limbal Scleral Dermoid Masquerading as Nodular Scleritis

Background: Dermoid cysts are one of the most common orbital lesions in childhood. They typically present as a palpable subcutaneous mass in the superotemporal region along the frontozygomatic suture. When involving the eye, ocular dermoids typically present as visible lesions at the limbus. Clinical Case Report: A five-year-old male presented with focal injection of the left nasal conjunctiva sparing the limbus that progressed to a non-mobile scleral nodule with overlying 3+ injection, tenderness to palpation, and minimal blanching with phenylephrine suspicious for nodular scleritis versus abscess. The inflammation improved, but the nodule persisted despite treatment with topical antibiotics, steroids, and oral NSAIDs. Superonasal subconjunctival excisional biopsy revealed an 8mm mass with a visible hair protruding from lesion, with pathological analysis revealing findings of acutely inflamed dermoid cyst. Discussion: To our knowledge, this is the first documented case of a non-limbal ocular dermoid masquerading as nodular scleritis.https://scholarlycommons.henryford.com/merf2020caserpt/1048/thumbnail.jp

Local flexibility market framework for grid support services to distribution networks

The increasing volume of distributed resources and user-dependent loads in local networks has increased the concern for congestion and voltage management in distribution networks. To mitigate these issues, the implementation of local flexibility markets has been proposed to assist distribution system operators (DSOs) to manage their networks efficiently. This paper presents the framework of a local flexibility market, including the market participants and their roles. This framework aims to empower DSOs with a market-based instrument for the alleviation of congestion incidents by exploiting the flexibility of local resources. The proposed market aims to provide a tool for the holistic management of distribution networks by trading both reservation and activation of flexibility services, indifferent of the type and the timeline of the needed service. Three market modes are proposed, i.e., long-term, short-term and real-time market, and the interactions among those modes are shown. The operation of the market is explained in detail, including the identification of the needed services, the activation of the market as well as the proposed bidding, clearing and settlement mechanisms. The modelling of the long-term and real-time markets is also presented, along with some indicative simulation results for long-term and real-time services. Finally, the future developments as well as the major conclusions are discussed

Energy Scheduling Strategies for Grid-connected Microgrids: A Case Study on Chalmers Campus

This paper focuses on the optimal energy managementof grid-connected microgrids with battery energy storagesystems. The microgrid energy management and the optimalpower flow of the distribution network are formulated as mixed-integerlinear optimization problems to evaluate microgrid energyscheduling strategies including cost minimization, maximum useof own resources, and minimum energy exchange with theupstream network. The real distribution network of ChalmersUniversity of Technology campus is used as a case study. Thestudy results show that economic optimization yields an annualmicrogrid cost reduction of 4%. Alternatively, if the microgridminimizes the energy exchange, virtual islanding operation (zeroenergy exchange) for 3211 hours can be achieved within a year.The results also present the effects on the operation and costof the distribution system and highlight a trade-off betweenmicrogrid cost minimization and battery lifetime

Complete genome sequence of Lutibacter profoundi LP1T isolatet from an Arctic deep-sea hydrothermal vent system

Lutibacter profundi LP1T within the family Flavobacteriaceae was isolated from a biofilm growing on the surface of a black smoker chimney at the Loki’s Castle vent field, located on the Arctic Mid-Ocean Ridge. The complete genome of L. profundi LP1T is the first genome to be published within the genus Lutibacter. L. profundi LP1T consists of a single 2,966,978 bp circular chromosome with a GC content of 29.8%. The genome comprises 2,537 protein-coding genes, 40 tRNA species and 2 rRNA operons. The microaerophilic, organotrophic isolate contains genes for all central carbohydrate metabolic pathways. However, genes for the oxidative branch of the pentose-phosphate-pathway, the glyoxylate shunt of the tricarboxylic acid cycle and the ATP citrate lyase for reverse TCA are not present. L. profundi LP1T utilizes starch, sucrose and diverse proteinous carbon sources. In accordance, the genome harbours 130 proteases and 104 carbohydrate-active enzymes, indicating a specialization in degrading organic matter. Among a small arsenal of 24 glycosyl hydrolases, which offer the possibility to hydrolyse diverse poly- and oligosaccharides, a starch utilization cluster was identified. Furthermore, a variety of enzymes may be secreted via T9SS and contribute to the hydrolytic variety of the microorganism. Genes for gliding motility are present, which may enable the bacteria to move within the biofilm. A substantial number of genes encoding for extracellular polysaccharide synthesis pathways, curli fibres and attachment to surfaces could mediate adhesion in the biofilm and may contribute to the biofilm formation. In addition to aerobic respiration, the complete denitrification pathway and genes for sulphide oxidation e.g. sulphide:quinone reductase are present in the genome. sulphide:quinone reductase and denitrification may serve as detoxification systems allowing L. profundi LP1T to thrive in a sulphide and nitrate enriched environment. The information gained from the genome gives a greater insight in the functional role of L. profundi LP1T in the biofilm and its adaption strategy in an extreme environment.publishedVersio

A toolbox for comparing congestion management solutions for distribution networks

To address the emerging challenges in electricity distribution networks, various solutions have been proposed such as alternative tariff design, local flexibility markets (LFMs), bilateral contracts, and local energy markets (LEMs). However, choosing a suitable solution is not straightforward due to multi-dimensional complexity of the challenges which may vary under different circumstances. This paper proposes a toolbox for qualitative and quantitative comparison of the different solutions. The toolbox includes a multi-dimensional analytical framework and a flexible modeling and demonstration platform for conducting quantitative comparison studies. Four solutions i.e. LFM, LEM, cost-reflective tariffs, and bilateral contracts are compared qualitatively using the framework and a real demonstration example of an LFM design is presented utilizing the modeling platform. The toolbox can facilitate research on the local grid challenges and contribute to finding a suitable solution from a multi-dimensional perspective