Automated Bilateral Trading of Energy by Alliances in Multi-Agent Electricity Markets

ABSTRACT: In liberalized markets, consumers can choose their electricity suppliers or be part of an energy community. The problem with communities is that they may not have enough weight to trade in markets, which can be overcome by forming coalitions. Electricity is traded in spot markets or through bilateral contracts involving consumers and suppliers. This paper is devoted to bilateral contracting, modeled as a negotiation process involving an iterative exchange of offers and counter-offers. It focuses on coalitions of energy communities. Specifically, it presents team and single-agent negotiation models, where each consumer has strategies, tactics, and decision models. Coalition agents are equipped with intra-team strategies and decision protocols. It also describes a study of bilateral contracts involving a seller agent and a coalition of energy communities. By allying into a coalition, members of energy communities reduced their average costs for electricity by between 2% (large consumers) and 64% (small consumers) according to their consumption. Their levelized cost reduction was 19%. The results demonstrate the power of coalitions when negotiating bilateral contracts and the benefit of a low-consumption members alliance with larger players.info:eu-repo/semantics/publishedVersio

Agent-based model of citizen energy communities used to negotiate bilateral contracts in electricity markets

ABSTRACT: The worldwide targets for carbon-neutral societies increased the penetration of distributed generation and storage. Smart cities now play a key role in achieving these targets by considering the alliances of their demand and supply assets as local citizen energy communities. These communities need to have enough weight to trade electricity in wholesale markets. Trading of electricity can be done in spot markets or by bilateral contracts involving customers and suppliers. This paper is devoted to bilateral contracting, which is modeled as a negotiation process involving an iterative exchange of offers and counter-offers. This article focuses on local citizen energy communities. Specifically, it presents team and single-agent negotiation models, where each member has its sets of strategies and tactics and also its decision model. Community agents are equipped with intra-team strategies and decision protocols. To evaluate the benefits of CECs, models of both coalition formation and management have been adapted. This paper also describes a case study on forward bilateral contracts, involving a retailer agent and three different types of citizen energy communities. The results demonstrate the benefits of CECs during the negotiation of private bilateral contracts of electricity. Furthermore, they also demonstrate that in the case of using a representative strategy, the selection of the mediator may be critical for achieving a good deal.info:eu-repo/semantics/publishedVersio

The Economic Sustainability of Variable Renewable Energy Considering the Negotiation of Different Support Schemes

ABSTRACT: The increase in the prices of fossil fuels and environmental issues are leading to a high investment in wind power and solar photovoltaic all over Europe, reducing its dependence on imported fossil fuels. The European countries started incentive programs for investment in these renewable technologies, which consisted of fixed and market premium feed-in tariffs. These feed-in schemes involve long-term contracts with updated prices over inflation. These incentives highly increase the investment and installation of new renewable capacity in Europe. They lead to high renewable penetrations in power systems but originate a tariff deficit due to the difference between market prices and the tariffs paid to these technologies. End-use consumers pay the tariff deficit on retail tariffs. This work analyzes the market-based remuneration of variable renewable energy considering different support schemes and the role of risk-sharing contracts in mitigating the spot price volatility. It presents models able to negotiate bilateral contracts considering risk management, notably risk attitude and risk sharing, bid establishment, and clause (by-laws) negotiation. Furthermore, to evaluate the economic sustainability of renewable generation in Spain, it presents a study for different 12-year support schemes starting in 2010. The results confirmed that, in the case of using risk-sharing contracts during crisis periods, the incidence of low energy prices (price "cannibalization") decreases, such as the tariff deficit. Furthermore, in the case of high-inflation periods, these contracts hedge against the increase in retail prices, resulting in an economic surplus for consumers.info:eu-repo/semantics/publishedVersio

The role of local citizen energy communities in the road to carbon-neutral power systems: outcomes from a case study in Portugal

ABSTRACT: Global warming contributes to the worldwide goal of a sustainable carbon-neutral society. Currently, hydroelectric, wind and solar power plants are the most competitive renewable technologies. They are limited to the primary resource availability, but while hydroelectric power plants (HPPs) can have storage capacity but have several geographical limitations, wind and solar power plants have variable renewable energy (VRE) with stochastic profiles, requiring a substantially higher investment when equipped with battery energy storage systems. One of the most affordable solutions to compensate the stochastic behaviour of VRE is the active participation of consumers with demand response capability. Therefore, the role of citizen energy communities (CECs) can be important towards a carbon-neutral society. This work presents the economic and environmental advantages of CECs, by aggregating consumers, prosumers and VRE at the distribution level, considering microgrid trades, but also establishing bilateral agreements with large-scale VRE and HPPs, and participating in electricity markets. Results from the case-study prove the advantages of CECs and self-consumption. Currently, CECs have potential to be carbon-neutral in relation to electricity consumption and reduce consumers' costs with its variable term until 77%. In the future, electrification may allow CECs to be fully carbon-neutral, if they increase their flexibility portfolio.info:eu-repo/semantics/publishedVersio

Management of local citizen energy communities and bilateral contracting in multi-agent electricity markets

ABSTRACT: Over the last few decades, the electricity sector has experienced several changes, resulting in different electricity markets (EMs) models and paradigms. In particular, liberalization has led to the establishment of a wholesale market for electricity generation and a retail market for electricity retailing. In competitive EMs, customers can do the following: freely choose their electricity suppliers; invest in variable renewable energy such as solar photovoltaic; become prosumers; or form local alliances such as Citizen Energy Communities (CECs). Trading of electricity can be done in spot and derivatives markets, or by bilateral contracts. This article focuses on CECs. Specifically, it presents how agent-based local consumers can form alliances as CECs, manage their resources, and trade on EMs. It also presents a review of how agent-based systems can model and support the formation and interaction of alliances in the electricity sector. The CEC can trade electricity directly with sellers through private bilateral agreements. During the negotiation of private bilateral contracts, the CEC receives the prices and volumes of their members and according to its negotiation strategy, tries to satisfy the electricity demands of all members and reduce their costs for electricity.info:eu-repo/semantics/publishedVersio

Least-cost non-RES thermal power plants mix in power systems with majority penetrations of renewable energy

ABSTRACT: The ambitious targets of the European Union (EU) for a greater penetration of renewable energy sources (RES) in all areas of activity have led to power systems with growing levels of variable RES (VRES) all over the EU. Considering these targets, the EU countries presented their National Energy and Climate Plans (NECP) with their expected capacity until 2030. The NECPs considered a relevant increase in the VRES capacity and in some cases a decrease in the capacity of dispatchable power plants. VRES have near-zero marginal costs and increase the volatility of the net-load due to the stochastic profile of their production. These characteristics increase the need to maintain fast-response dispatchable power plants to guarantee the security of supply and also decrease market prices. Thus, governments promote externalities, as capacity mechanisms and other incentives to these players, guaranteeing their economic sustainability. This study presents the optimization of the non-RES thermal capacity of the Iberian power system by 2030, considering the least-cost algorithm. Considering a cooperative scenario between Portugal and Spain, it is possible to reduce the system costs by 17.40%, the curtailments quantity by 21.93%, the number of market-splitting hours by 43.26% and the dioxide carbon emissions by 4.76%.info:eu-repo/semantics/publishedVersio

Simple and linear bids in multi-agent daily electricity markets: a preliminary report

ABSTRACT: Variable generation (VG) has several unique characteristics compared to those of traditional thermal and hydro-power plants, notably significant fixed capital costs, but near-zero or zero variable production costs. Increasing the penetration of VG tend to reduce energy prices over time, increase the occurrence of zero or negatively priced periods, and reduce the cleared energy levels of existing plants. This paper presents an overview of an agent-based system, called MATREM, to simulate electricity markets. Special attention is devoted to a case study that aims at analyzing the behavior of a simulated day-ahead market in situations with increasing levels of wind generation, and also comparing market schedules and prices in situations involving either simple and linear bids.info:eu-repo/semantics/publishedVersio

Participation of wind power producers in day-ahead and balancing markets: an overview and a simulation-based study

ABSTRACT: At present, a harmonized pan-European electricity market (EM) is a close reality. While in day-ahead markets (DAMs) the harmonization is at an advanced stage, in balancing markets (BMs) still exist some challenging issues, notably the remuneration of imbalances: some countries have simple and clear methods, but others consider complex methods that are not appealing to the participation of variable renewable energy (VRE). The participation of VRE in BMs is technically feasible, although with some restrictions to guarantee security and stability. Thus the economic attractiveness of these markets should be increased in order to enable full integration of VRE without feed-in-tariffs or other incentives. This article presents an overview of EMs, focusing on European BMs, and also investigates the benefits of the participation of wind power producers (WPPs) in BMs at both economic and technical levels. In particular, the article presents a new strategy allowing WPPs to bid in BMs. It also presents a study involving four scenarios, where WPPs participate in: (a) the DAM (baseline scenario), (b) the DAM and the automatic-activated frequency restoration reserve market, (c) the DAM and the manually activated FRR (mFRR) market, and (d) the DAM and a 15-min mFRR market. The simulations are performed with the agent-based system MATREM (for Multi-Agent TRading in EMs). For the last scenario, the results indicate an increase around 6% in the wind energy value to the market, a decrease of 12% in the total reserve used, and a decrease around 16% in the costs from the BM. This article is categorized under: Wind Power > Systems and Infrastructure Wind Power > Economics and Policy Energy Systems Analysis > Economics and Policy.info:eu-repo/semantics/publishedVersio

Changing the day-ahead gate closure to wind power integration: a simulation-based study

ABSTRACT: Currently, in most European electricity markets, power bids are based on forecasts performed 12 to 36 hours ahead. Actual wind power forecast systems still lead to large errors, which may strongly impact electricity market outcomes. Accordingly, this article analyzes the impact of the wind power forecast uncertainty and the change of the day-ahead market gate closure on both the market-clearing prices and the outcomes of the balancing market. To this end, it presents a simulation-based study conducted with the help of an agent-based tool, called MATREM. The results support the following conclusion: a change in the gate closure to a time closer to real-time operation is beneficial to market participants and the energy system generally.info:eu-repo/semantics/publishedVersio

Variable renewable energy and market design: new products and a real-world study

ABSTRACT: Most existing energy markets (EMs) were not designed to take into account an active participation of variable renewable energy (VRE). This situation results typically in imbalances and substantial costs in balancing markets. Such costs are reflected both in the energy and the VRE parts of the consumer tariffs. Both appropriate market products and new elements of market design may largely facilitate the large-scale integration of VRE in EMs. Accordingly, this article presents a new bilateral energy contract and introduces two new marketplaces that can contribute to reduce the imbalances resulting from VRE producers. It also presents a study conducted with the help of an agent-based tool, called MATREM. The results indicate a significant decrease in the imbalances and the associated costs.info:eu-repo/semantics/publishedVersio