9 research outputs found
Stochastic Framework for Strategic Decision-making of Load-serving Entities for Day-ahead Market
The deregulation of electricity markets has
diversified the range of financial transaction modes between
independent system operator (ISO), generation companies
(GENCO) and load-serving entities (LSE) as the main
interacting players of a day-ahead market (DAM). LSEs sell
electricity to end-users and retail customers. The LSE that owns
distributed generation (DG) or energy storage units can supply
part of its serving loads when the nodal price of electricity rises.
This opportunity stimulates them to have storage or generation
facilities at the buses with higher locational marginal prices
(LMP). The short-term advantage of this model is reducing the
risk of financial losses for LSEs in DAMs and its long-term
benefit for the LSEs and the whole system is market power
mitigation by virtually increasing the price elasticity of demand.
This model also enables the LSEs to manage the financial risks
with a stochastic programming framework
Coordination between mid-term maintenance outage decisions and short-term security-constrained scheduling in smart distribution systems
Distribution systems are the first volunteers experiencing the benefits of smart grids. The smart grid concept impacts the internal legislation and standards in grid-connected and isolated distribution systems. Demand side management, the main feature of smart grids, acquires clear meaning in low voltage distribution systems. In these networks, various coordination procedures are required between domestic, commercial and industrial consumers, producers and the system operator. Obviously, the technical basis for bidirectional communication is the prerequisite of developing such a coordination procedure. The main coordination is required when the operator tries to dispatch the producers according to their own preferences without neglecting its inherent responsibility. Maintenance decisions are first determined by generating companies, and then the operator has to check and probably modify them for final approval. In this paper the generation scheduling from the viewpoint of a distribution system operator (DSO) is formulated. The traditional task of the DSO is securing network reliability and quality. The effectiveness of the proposed method is assessed by applying it to a 6-bus and 9-bus distribution system
Local Electricity Markets for Electric Vehicles: An Application Study Using a Decentralized Iterative Approach
Local electricity markets are emerging solutions to enable local energy trade for the end
users and provide grid support services when required. Various models of local electricity
markets (LEMs) have been proposed in the literature. The peer-to-peer market model appears
as a promising structure among the proposed models. The peer-to-peer market structure
enables electricity transactions between the players in a local energy system at a lower cost. It
promotes the production from the small low–carbon generation technologies. Energy
communities can be the ideal place to implement local electricity markets as they are
designed to allow for larger growth of renewable energy and electric vehicles, while
benefiting from local transactions. In this context, a LEM model is proposed considering
an energy community with high penetration of electric vehicles in which prosumer-to-vehicle
(P2V) transactions are possible. Each member of the energy community can buy electricity from
the retailer or other members and sell electricity. The problem is modeled as a mixed-integer
linear programing (MILP) formulation and solved within a decentralized and iterative process. The
decentralized implementation provides acceptable solutions with a reasonable execution time,
while the centralized implementation usually gives an optimal solution at the expense of reduced
scalability. Preliminary results indicate that there are advantages for EVs as participants of the
LEM, and the proposed implementation ensures an optimal solution in an acceptable execution
time. Moreover, P2V transactions benefit the local distribution grid and the energy community.This work has received funding from FEDER Funds through COMPETE program and from National Funds through (FCT) under the projects CENERGETIC (PTDC/EEI-EEE/28983/2017), CEECIND/02814/2017 (JS grant), SFRH/BD/133086/2017 (RF PhD grant). We also acknowledge the work facilities and equipment provided by GECAD research center (UIDB/00760/2020) to the project team. Brazilian Federal Agency for Support and Evaluation of Graduate Education (CAPES), in the scope of the Program CAPES-PrInt, process number 88887.310463/2018-00, International Cooperation Project number 5-P2-1479.info:eu-repo/semantics/publishedVersio
Multiagent System Architecture for Short-term Operation of Integrated Microgrids
The forthcoming smart grids are comprised of integrated microgrids operating in grid-connected
and isolated mode with local generation, storage and demand response (DR) programs. The proposed
model is based on three successive complementary steps for power transaction in the market environment.
The first step is characterized as a microgrid’s internal market; the second concerns negotiations between
distinct interconnected microgrids; and finally, the third refers to the actual electricity market. The
proposed approach is modeled and tested using a MAS framework directed to the study of the smart grids
environment, including the simulation of electricity markets. This is achieved through the integration of
the proposed approach with the MASGriP (Multi-Agent Smart Grid Platform) system
Stochastic short-term maintenance scheduling of GENCOs in an oligopolistic electricity market
In the proposed model, the independent system operator (ISO) provides the opportunity for maintenance outage rescheduling of generating units before each short-term (ST) time interval. Long-term (LT) scheduling for 1 or 2 years in advance is essential for the ISO and the generation companies (GENCOs) to decide their LT strategies; however, it is not possible to be exactly followed and requires slight adjustments. The Cournot-Nash equilibrium is used to characterize the decision-making procedure of an individual GENCO for ST intervals considering the effective coordination with LT plans. Random inputs, such as parameters of the demand function of loads, hourly demand during the following ST time interval and the expected generation pattern of the rivals, are included as scenarios in the stochastic mixed integer program defined to model the payoff-maximizing objective of a GENCO. Scenario reduction algorithms are used to deal with the computational burden. Two reliability test systems were chosen to illustrate the effectiveness of the proposed model for the ST decision-making process for future planned outages from the point of view of a GENCO
A regulatory framework for short-term stochastic maintenance outage scheduling in smart grids
The current regulatory framework for maintenance outage scheduling in distribution systems needs revision to face
the challenges of future smart grids. In the smart grid context, generation units and the system operator perform new roles with different objectives, and an efficient coordination between them becomes necessary. In this paper, the distribution system operator (DSO) of a microgrid receives the proposals for shortterm (ST) planned outages from the generation and transmission side, and has to decide the final outage plans, which is mandatory for the members to follow. The framework is based on a coordination procedure between the DSO and other market players. This paper undertakes the challenge of optimization problem in a smart grid where the operator faces with
uncertainty. The results show the effectiveness and applicability of the proposed regulatory framework in the modified IEEE 34- bus test system
Stochastic Short-term Incentive-based Demand Response Scheduling of Load-serving Entities
In competitive electricity markets it is necessary for a
profit-seeking load-serving entity (LSE) to optimally adjust the
financial incentives offering the end users that buy electricity at
regulated rates to reduce the consumption during high market
prices. The LSE in this model manages the demand response
(DR) by offering financial incentives to retail customers, in
order to maximize its expected profit and reduce the risk of
market power experience. The stochastic formulation is
implemented into a test system where a number of loads are
supplied through LSEs
Notes for genera – Ascomycota
Knowledge of the relationships and thus the classification of fungi, has developed rapidly with increasingly widespread use of molecular techniques, over the past 10--15 years, and continues to accelerate. Several genera have been found to be polyphyletic, and their generic concepts have subsequently been emended. New names have thus been introduced for species which are phylogenetically distinct from the type species of particular genera. The ending of the separate naming of morphs of the same species in 2011, has also caused changes in fungal generic names. In order to facilitate access to all important changes, it was desirable to compile these in a single document. The present article provides a list of generic names of Ascomycota (approximately 6500 accepted names published to the end of 2016), including those which are lichen-forming. Notes and summaries of the changes since the last edition of `Ainsworth Bisby's Dictionary of the Fungi' in 2008 are provided. The notes include the number of accepted species, classification, type species (with location of the type material), culture availability, life-styles, distribution, and selected publications that have appeared since 2008. This work is intended to provide the foundation for updating the ascomycete component of the ``Without prejudice list of generic names of Fungi'' published in 2013, which will be developed into a list of protected generic names. This will be subjected to the XIXth International Botanical Congress in Shenzhen in July 2017 agreeing to a modification in the rules relating to protected lists, and scrutiny by procedures determined by the Nomenclature Committee for Fungi (NCF). The previously invalidly published generic names Barriopsis, Collophora (as Collophorina), Cryomyces, Dematiopleospora, Heterospora (as Heterosporicola), Lithophila, Palmomyces (as Palmaria) and Saxomyces are validated, as are two previously invalid family names, Bartaliniaceae and Wiesneriomycetaceae. Four species of Lalaria, which were invalidly published are transferred to Taphrina and validated as new combinations. Catenomycopsis Tibell Constant. is reduced under Chaenothecopsis Vain., while Dichomera Cooke is reduced under Botryosphaeria Ces. De Not. (Art. 59)