Browsing by Author "Lopes, Fernando"
Now showing 1 - 7 of 7
Results Per Page
Sort Options
- Bilateral contracting in multi-agent energy markets with demand responsePublication . Lopes, Fernando; Algarvio, Hugo; Sousa, Jorge A. M.In competitive energy markets (EMs), customers can freely choose their energy suppliers. The electricity trade can be done in organized markets or using forward bilateral contracts. Currently, there are several simulation tools based on multi-agent techniques that allow modeling, partially or globally, competitive EMs. The existing tools allow simulating negotiation prices and volumes through bilateral contracts, transactions in pool markets, etc. However, these tools have some limitations, mainly due to the complexity of the electric system. In this context, this article focuses on bilateral trading and presents the key features of software agents able to negotiate forward bilateral contracts. Special attention is devoted to demand response in bilateral contracting, notably utility functions and trading strategies for promoting demand response. The article also presents a case study on forward bilateral contracting with demand response: a retailer agent and an industrial customer agent negotiate a 24h-rate tariff.
- Multi-agent simulation of bilateral contracting in competitive electricity marketsPublication . Lopes, Fernando; Algarvio, Hugo; Sousa, Jorge A. M.; Helder Coelho; Pinto, Tiago; Santos, Gabriel; Zita Vale; Isabel PracaTraditional vertically integrated power utilities around the world have evolved from monopoly structures to open markets that promote competition among suppliers and provide consumers with a choice of services. Market forces drive the price of electricity and reduce the net cost through increased competition. Electricity can be traded in both organized markets or using forward bilateral contracts. This article focuses on bilateral contracts and describes some important features of an agent-based system for bilateral trading in competitive markets. Special attention is devoted to the negotiation process, demand response in bilateral contracting, and risk management. The article also presents a case study on forward bilateral contracting: a retailer agent and a customer agent negotiate a 24h-rate tariff. © 2014 IEEE.
- Multi-agent Simulation of Bilateral Contracting in Competitive Electricity MarketsPublication . Lopes, Fernando; Algarvio, Hugo; Sousa, Jorge A. M.; Helder Coelho; Pinto, Tiago; Santos, Gabriel; A. Vale, Zita; Praça, IsabelTraditional vertically integrated power utilities around the world have evolved from monopoly structures to open markets that promote competition among suppliers and provide consumers with a choice of services. Market forces drive the price of electricity and reduce the net cost through increased competition. Electricity can be traded in both organized markets or using forward bilateral contracts. This article focuses on bilateral contracts and describes some important features of an agent-based system for bilateral trading in competitive markets. Special attention is devoted to the negotiation process, demand response in bilateral contracting, and risk management. The article also presents a case study on forward bilateral contracting: a retailer agent and a customer agent negotiate a 24h-rate tariff. © 2014 IEEE.
- Power producers trading electricity in both pool and forward marketsPublication . Algarvio, Hugo; Lopes, Fernando; Sousa, Jorge A. M.; Lagarto, JoãoThe electricity industry throughout the world, which has long been dominated by vertically integrated utilities, has experienced major changes. Deregulation, unbundling, wholesale and retail wheeling, and real-time pricing were abstract concepts a few years ago. Today market forces drive the price of electricity and reduce the net cost through increased competition. As power markets continue to evolve, there is a growing need for advanced modeling approaches. This article addresses the challenge of maximizing the profit (or return) of power producers through the optimization of their share of customers. Power producers have fixed production marginal costs and decide the quantity of energy to sell in both day-ahead markets and a set of target clients, by negotiating bilateral contracts involving a three-rate tariff. Producers sell energy by considering the prices of a reference week and five different types of clients with specific load profiles. They analyze several tariffs and determine the best share of customers, i.e., the share that maximizes profit. © 2014 IEEE.
- Power Producers Trading Electricity in Both Pool and Forward MarketsPublication . Algarvio, Hugo; Lopes, Fernando; Sousa, Jorge A. M.; Lagarto, JoãoThe electricity industry throughout the world, which has long been dominated by vertically integrated utilities, has experienced major changes. Deregulation, unbundling, wholesale and retail wheeling, and real-time pricing were abstract concepts a few years ago. Today market forces drive the price of electricity and reduce the net cost through increased competition. As power markets continue to evolve, there is a growing need for advanced modeling approaches. This article addresses the challenge of maximizing the profit (or return) of power producers through the optimization of their share of customers. Power producers have fixed production marginal costs and decide the quantity of energy to sell in both day-ahead markets and a set of target clients, by negotiating bilateral contracts involving a three-rate tariff. Producers sell energy by considering the prices of a reference week and five different types of clients with specific load profiles. They analyze several tariffs and determine the best share of customers, i.e., the share that maximizes profit. © 2014 IEEE.
- Response of Fogo volcano (Cape Verde) to lunisolar gravitational forces during the 2014-2015 eruptionPublication . Dumont, Stéphanie; Silveira, Graça; Custódio, Susana; Lopes, Fernando; Le Mouel, Jean-Louis; Gouhier, Mathieu; GUEHENNEUX, YannickVolcanoes are complex systems that evolve in space and time as a result of their eruptive activity. Volcanic eruptions represent the ultimate expression of a complex interplay between internal and external processes that span across different time scales. Deciphering how internal and external processes interact at the time scale of eruptions may provide key insights on the temporal evolution of eruptions and also help to better evaluate associated volcanic hazards. Studies of the tidal influence on volcanic activity have fallen within this context, although the cause-effect relationship between tides and eruptions is still unclear. In this study, we used Singular Spectrum Analysis to analyze three time-series, namely the seismic tremor, SO2 emission and lava volume flow rate, which cover the first month of effusive activity at Fogo volcano, Cape Verde, in 2014-2015. We detect 9 tidal periodicities and up to 5 in each time-series ranging from semi-diurnal to fortnightly periods. We show that the movement of magma at crustal depths and at surface as well as gas emission during the effusive eruption are all modulated by lunisolar gravitational forces. We highlight the relevance of the volcano location on Earth, which together with the timing of the eruption, associated with a specific astronomical configuration, result in a specific combination of tides that directly influence the volcano eruptive activity. With this data set, we further investigate the response of Fogo volcano to this external forcing. We show that during the 2014-2015 eruption, Fogo volcano acted as a bandpass filter to quasi-permanent tidal oscillations.
- A trader portfolio optimization of bilateral contracts in electricity retail marketsPublication . Algarvio, Hugo; Lopes, Fernando; Sousa, Jorge A. M.; Lagarto, JoãoElectricity markets are systems for effecting the purchase and sale of electricity using supply and demand to set energy prices. Two major market models are often distinguished: pools and bilateral contracts. Pool prices tend to change quickly and variations are usually highly unpredictable. In this way, market participants often enter into bilateral contracts to hedge against pool price volatility. This article addresses the challenge of optimizing the portfolio of clients managed by trader agents. Typically, traders buy energy in day-ahead markets and sell it to a set of target clients, by negotiating bilateral contracts involving three-rate tariffs. Traders sell energy by considering the prices of a reference week and five different types of clients. They analyze several tariffs and determine the best share of customers, i.e., the share that maximizes profit. © 2014 IEEE.