A América Latina tem se tornado nos últimos anos uma das regiões mais dinâmicas para os mercados de energia elétrica, sendo marcada por elevadas taxas de crescimento da demanda, forte participação hidroelétrica e expressiva necessidade de investimentos privados. O processo de reforma dos setores elétricos até o momento ainda não alcançou todos os países da região e ocorreu em “ondas” nos países que hoje possuem mercados desregulados. O processo de reforma iniciado pelo Chile no inicio da década de 80 foi seguido pela Argentina no início dos anos 90 e, pouco depois, pela Bolívia e pelo Peru. Em meados da década de 90, estendeu-se ao Brasil, à Colômbia e a vários países da América Central. Esta “primeira onda” da reformas continha bastantes elementos comuns entre os países e, particularmente, uma forte inspiração nas reformas do mercado elétrico da Inglaterra, desregulado em 1990. Após um período de sucessos e falhas, de 2004 a 2008 alguns países desta região, sobretudo da América do Sul, realizaram ajustes em seus modelos regulatórios. Estes ajustes tinham por objetivo manter os aspectos positivos da primeira “onda” mas, ao mesmo tempo, corrigir aqueles que não funcionaram conforme esperado, sobretudo os relacionados à necessidade de assegurar uma expansão da geração para atender o forte crescimento da demanda de maneira suficiente. Embora as iniciativas de cada país tenham sido independentes, observou-se uma convergência a um modelo comum de mercado para garantir a suficiência com eficiência na geração. Os ingredientes desta “segunda onda” incluem: (i) incentivos a contratos a termo de forma a induzir a entrada de nova capacidade (a chamada “competição pelo mercado” ao invés de “competição no mercado”) com obrigatoriedade da existência de lastro físico para sua cobertura visando a suficiência de geração e (ii) uso de leilões como mecanismo de incentivo à contratação eficiente e estabelecimento de preços de repasse realistas.
Este documento é um capítulo de um livro em organização pelo comité C5 do Cigré Brasil e tem como objetivo apresentar uma visão geral do processo de implementação e características desta segunda geração de modelos regulatórios no setor de geração de países latino-americanos visando identificar os desafios comuns e os esquemas adotados para enfrentá-los, tais como o uso de leilões de contratação, as estratégias para lidar com a incerteza na previsão de demanda, a expansão da capacidade e o grau de intervenção do estado, dentre outros.

Since the liberalization of the power industry, there has been a large amount of literature on the determination of optimal bidding decisions for price maker energy producers. The vast majority of the work developed so far has focused on short-term horizons and may be viewed as successful approaches for systems whose operation is generally deterministic. In the case of price maker hydro plants with significant storage capacity, however, the solution of the strategic bidding problem is more subtle. The reason is that hydro reservoirs allow the bidder to postpone energy production if future prices are expected to be higher than the current price. This demands the management of an energy-constrained resource and determines a time-coupling characteristic to the problem, implying that the bidding strategy should ideally take into account the following stages and consider the stochasticity of inflows. These aspects characterize the strategic bidding for price maker hydro agents as a multi-stage stochastic programming problem, with significant computational challenges. The objective of this work is to present a new methodology for the strategic bidding problem of a price-maker hydropower based company, taking into account several hydro plants, time-coupling and stochastic inflow scenarios. The proposed approach considers a deterministic residual demand curve and is based on stochastic dual dynamic programming (SDDP), which has been successfully applied to the least-cost hydrothermal scheduling problem. Since the technique requires the problem to be concave, a piecewise linear approximation of the expected future benefit function is proposed. The application of the methodology is exemplified with a real case study based on the hydrothermal system of El Salvador.

Energy is recognized as one of the single most important issues in modern society, having high impact in the social and economic development. The quality of human development is dependant, among other factors, on energy supply being available, efficient, reliable and sustainable. Particularly in Latin America, energy plays an essential role in social development and it is perceived as of strategic importance for economic development. The primary challenge faced by the countries in Latin America is to ensure sufficient capacity and investment to serve reliably their growing economies. Social and environmental concerns are an inherent challenge and also must be addressed accordingly. Energy supply can determine competitiveness in a global market, where economic activities must compete not only in a local market, or even regional, but in a global context. Energy policy is certainly conditioned by energy sources available, energy consumption growth, general social and political context, among other factors, but also by history. Due to recent events, Latin America energy policy decisions have been based upon different crisis, where lack of investment drove to lack of supply security and to inefficiency of supply. These remain to be key issues in the region. Nonetheless, climate change has drawn attention away from these key issues, often avoiding policy making to focus on main issues. So then again, one single question remains to be answered in Latin America: What are the economics that balance the equation that considers all the key aspects of an energy policy? This article addresses these issues.

Brazil is one of the world leaders in the use of renewable power. In addition to “mainstream” hydropower, which has historically dominated the country’s electricity production, two renewable sources have become competitive for large scale expansion in the last five years: bioelectricity (BE), cogeneration from sugarcane bagasse; and small hydro (SH), which comprises hydro plants smaller than 30 MW. About 8,000 MW of BE and SH plants are already in operation or under construction. This paper describes the technical and regulatory solutions to the planning, construction and remuneration of the transmission network that integrates them to the main grid. The planning issue is complex because the plants are spread over large areas. As a consequence, the integration network has layers of “collector stations” at different voltages. The optimal design of the network topology plus the siting and sizing of collector stations was solved by a new nonlinear integer programming algorithm. The second hurdle results from the potential conflicts of competing generators trying to jointly procure the construction of a shared network. The solution was to auction the network construction under the supervision of a third party, the national electricity regulator (ANEEL). The final obstacle, allocation of the auctioned network cost among generators, was solved by a MWmile scheme. The above set of methodologies and regulations was first applied to the integration of about 80 BE and SH plants, totaling 4,100 MW, spread over an area equivalent to half of California. The construction of the 2,500km integration network was auctioned in November 2008; operation starts by July 2010. This regulatory solution is also being considered for the integration of wind power, which has emerged the fourth “asset” of the country’s “renewable portfolio”, with 800 MW in operation and under construction, plus a 1,500MW contracting auction scheduled for the third quarter of 2009.

The firm energy of generation plants is a critical component in some electricity markets. It is usually calculated by the regulator and sets a cap to the amount a plant can trade in capacity markets (or auctions), in order to avoid free-riding behaviors. Firm energy is a systemic property and, in case of hydro plants, a synergy is observed whenever a cooperative operation occurs, i.e., the firm energy of a system is greater than the sum of the individual plants. This immediately raises the question of how to divide the system’s firm energy among the individual hydro plants. The objective of this work is to investigate the application of different allocation methods of firm energy rights among hydro plants using a game-theoretic framework. It is shown that there is not an optimal and unique approach to make this allocation. The paper investigates the advantages and disadvantages of different methods, such as marginal allocation, average production during the critical period, incremental allocation, finally recommending the Aumann–Shapley as the allocation method. This method is tested for the Brazilian power system, which has around 100 hydro plants. The results obtained are compared with the current allocation adopted by the electricity regulatory agency of Brazil.

The adequacy problem in electricity market is becoming a very important issue as there is neither theoretical proof nor practical evidence of correct delivering of sufficient and timely generation capacity when it is needed in a real (imperfect) environment. In contrast, classical market design seems to fail when facing high demand growth and/or large hydro share as seen in several Latin American countries such as Chile, Brazil, Colombia and Peru among others. Currently, various mechanisms have arisen across this region with the intention of stimulating energy procurement and new investment. These are mainly based on long-term contract and options obligations, which are allocated through auctions. Auction theory then becomes very important to ensure optimal allocation and efficient prices for both the new generation and the end user. However, difficulties arise when applying pure auction theory because basic hypotheses are not met by most electricity markets. The objective of this paper is to address and discuss the Latin American experience with auction design for long-term contracts focusing on practical design and theory. The different mechanisms and auctions for ensuring supply adequacy are listed along with theoretical justification as part of the potential solution for the adequacy problem that different economies have proposed.

Renewable sources have recently emerged as a generation option for many countries in order to promote clean energy development. In the case of Brazil, small hydro plants and cogeneration from sugarcane waste (bagasse) have been attractive alternatives during the past years, with hundreds of MW installed since 2004. Despite their advantages, both alternatives are hindered by seasonal yet complementary availability. This forces producers to discount (or price) the risks faced when selling firm energy contracts and may ultimately lead to projects being commercially unattractive. We propose a stochastic optimization model that defines the optimal composition of a portfolio based on these two renewable sources in order to maximize the revenue of an energy trading company. At the same time, this model mitigates hydrological and fuel unavailability risks, thus allowing the participation of both sources in the forward market environment in a competitive manner. A case study is presented, based on data from the Brazilian system.

Historicamente o Setor Elétrico Brasileiro tem utilizado a duração do período crítico, como medida para a capacidade de regularização do sistema. O período crítico é obtido de modelos que calculam a energia firme das usinas hidrelétricas. Entretanto, como estes modelos representam a operação das termoelétricas na base, a complementaridade entre estas usinas e as hidrelétricas não é considerada. Este trabalho tem como objetivos principais: (i) definir uma medida para a capacidade de regularização do sistema que leve em consideração a complementaridade termoelétrica; (ii) analisar através desta medida a capacidade de regularização atual do sistema elétrico brasileiro; e (iii) analisar a potencial perda de sua capacidade de regularização no longo prazo devido à entrada em operação cada vez mais freqüente de usinas a fio d’água, dentre outros motivos, por restrições ambientais que dificultam a construção de grandes reservatórios.

Os leilões de contratos por disponibilidade vêm sendo utilizados desde 2005 para a inserção de nova capacidade termelétrica no Brasil. Estes contratos funcionam como uma opção de compra para o consumidor. Como nestes leilões é permitido que os geradores ofereçam o preço de exercício e o prêmio, o principal desafio está na definição de um mecanismo que permita selecionar as melhores ofertas para o consumidor. Este artigo discute a utilização do ICB para a seleção das ofertas nos leilões, apresentando suas propriedades matemáticas e analisando como distorções de sua aplicação podem afetar a modicidade tarifária para o consumidor.

A operação do SEB caracteriza-se pela forte predominância geração hidroelétrica e o despacho das usinas é otimizado através da utilização de ferramentas que não são capazes de sinalizar a necessidade de geração térmica com a antecedência necessária reverter cenários de afluências mais adversos. Por esta razão, o ONS propôs a aplicação de Procedimentos Operativos de Curto Prazo, de forma a complementar o despacho com geração térmica adicional. Propõe-se avaliar a eficiência deste procedimento através do cálculo de um índice custo/benefício que representa o custo adicional pelo aumento da segurança operativa. Resultados são obtidos com base no PMO de Novembro/2008.