Browsing by Author "Watts, David"

Now showing 1 - 9 of 9
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    COMPETENCY IN THE CHILEAN BANKING SECTOR A dynamic approximation
    (FONDO CULTURA ECONOMICA, 2012) Flores, Yarela; Watts, David
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    Economic Model of Ancillary Services in Real Time for Frequency Control
    (2023) Balzer, Kristian; Lazo, Joaquin; Watts, David
    Modern power systems integrate ancillary services (ASs) to provide security and quality of service in real-time operation (RTO) due to the intense frequency variations caused by the uncertainty of solar-wind generation. To this end, the ancillary services market focuses on power reserves for secondary and tertiary frequency control. The adjustment and dispatch of reserves from plants are manual instructions executed by the system operator in order to maintain the frequency within the normal operating range (49.80 & LE; f & LE; 50.20 Hz). This work proposes a methodology for the economic modeling of the ancillary services market in real time using a dynamic hourly mathematical model that integrates the variability of solar-wind generation, a demand monitoring curve, and the trajectory of marginal cost (MgC). This is a segmented methodology in which plants with costs close to the marginal cost are identified in real time using the Supramarginal (SMg) and Inframarginal (IMg) methods. Finally, this economic model for real-time power reserve reallocation represents an innovation in the ancillary services market because its results allow for the operation costs (OC) of the reserves to be reduced by up to 60% and for the displacement of marginal costs to be reduced by 10 to 40% with respect to traditional methodologies such as the economic merit list and the technical minimum methodology, which cause plants to operate without economic justification.
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    From blackouts to breakthroughs: Examining electricity's relevance in healthcare during COVID-19 and the future role of renewable energy
    (2023) Lazo, Joaquin; Escobar, Carolina; Watts, David
    Power supply played a critical role during the COVID-19 pandemic in keeping hospitals and critical medical equipment operating, which was quickly reflected in electricity consumption and new consumption patterns. However, not all countries faced the same challenges. While developed countries could react adequately to changes in hospital electricity consumption patterns, low-income countries faced infrastructure and energy ac-cess challenges during the pandemic, which hampered the management of the pandemic in all of its dimensions. This paper reviews the importance of power supply in hospitals through a literature review and divides the discussion into three sections. First, the factors influencing new hospital consumption patterns during the pandemic are discussed. Then, the consequences of the lack of electricity in remote areas on managing the pandemic are reviewed. Finally, the impact of the pandemic on the design of hybrid power generation systems is reviewed, which must not only provide autonomy for similar future scenarios but also be prepared to respond to sudden increases in power consumption due to a greater number of patients or longer working hours, an increase in the number of critical loads, and possible restrictions on access to fuel. Thus, this work provides valuable insights for policymakers, academics, and researchers on the importance of updating hospital power supply standards and contributes to demonstrating the need to electrify remote hospitals.
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    Impacts of wind and solar spatial diversification on its market value: A case study of the Chilean electricity market
    (2019) Perez Odeh, Rodrigo; Watts, David
    Renewable energy is expected to become the main electricity source in the world in the coming decades, with solar and wind power taking a big share of the energy supply. Although there has been a remarkable advance on renewable energy technologies, their integration is still difficult for regulators, market designers and system operators due to the high variability and limited predictability of solar and wind resources. Measures can be adopted to ease their integration, among them geographical diversification. There is plenty of literature about the diversification of solar and wind resources and there is a common conclusion: greater dispersion smooths out power production. However, literature on the effects of spatial diversification on the power system, electricity prices and renewable energy market value is much scarcer. This paper studies the effects of spatial diversification and questions whether integration policies are incentivizing the placement of renewable generators where they provide the highest value to the electricity system in Chile. Using real data and a simplified dispatch model the analysis presented shows evidence of the effects of diversification on wind and solar market value in Chile. Results suggest that spatial diversification has a strong positive effect on the market value of renewable energy, especially in scenarios with active transmission and hydro-storage constraints. Wind market value may vary up to US$10/MW h depending on the level of diversification and the spatial and temporal constraints of the system and, given current storage capacity of hydro reservoirs, the solar market value may increase US$5/MW h due to diversification if transmission capacity is enough. Even though these results must be observed with caution, because they depend on the assumptions made, there is an important effect of renewable spatial diversification that should be observed by regulators.
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    Redispatch Model for Real-Time Operation with High Solar-Wind Penetration and Its Adaptation to the Ancillary Services Market
    (2024) Balzer, Kristian; Watts, David
    Modern electrical power systems integrate renewable generation, with solar generation being one of the pioneers worldwide. In Latin America, the greatest potential and development of solar generation is found in Chile through the National Electric System. However, its energy matrix faces a crisis of drought and reduction of emissions that limits hydroelectric generation and involves the definitive withdrawal of coal generation. The dispatch of these plants is carried out by the system operator, who uses a simplified mechanism, called "economic merit list" and which does not reflect the real costs of the plants to the damage of the operating and marginal cost of the system. This inefficient dispatch scheme fails to optimize the availability of stored gas and its use over time. Therefore, a real-time redispatch model is proposed that minimizes the operation cost function of the power plants, integrating the variable generation cost as a polynomial function of the net specific fuel consumption, adding gas volume stock restrictions and water reservoirs. In addition, the redispatch model uses an innovative "maximum dispatch power" restriction, which depends on the demand associated with the automatic load disconnection scheme due to low frequency. Finally, by testing real simulation cases, the redispatch model manages to optimize the operation and dispatch costs of power plants, allowing the technical barriers of the market to be broken down with the aim of integrating ancillary services in the short term, using the power reserves in primary (PFC), secondary (SCF), and tertiary (TCF) frequency control.
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    Regulatory response to COVID-19 in the Ibero-American electricity sector: Policy implications and critical analysis of support measures
    (2023) Aguirre, Gerson; Lazo, Joaquin; Watts, David
    The confinement measures implemented to curb the spread of COVID-19 caused massive job destruction and increased residential electricity consumption due to the increased time people spent in their homes, putting millions of people around the world at risk of energy poverty at a time when they depended on it for tele-commuting, distance learning, recreation, and communication. Governments reacted quickly and introduced various emergency measures to secure the power supply. This article reviews and classifies the emergency measures implemented in the electricity sector in 22 Ibero-American countries, identifying the validity of the measures, the benefits provided, and the requirements to apply. The paper focuses on economic support mea-sures for residential customers. The main measures include the prohibition of disconnection of electricity service, deferment of payment of the electricity bill, installment payments of the electricity debt, and reduction of the electricity tariff. However, measures aimed at commercial and industrial customers and companies participating in the electricity supply chain are also reviewed. We argue that these measures, applicable not only during health crises but also during any event that confines the population for an extended period, should be targeted at the most vulnerable population to reduce fiscal expenditure and increase social impact.
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    Statistical analysis of wind energy in Chile
    (PERGAMON-ELSEVIER SCIENCE LTD, 2011) Watts, David; Jara, Danilo
    Bearing in mind the current and pressing need for an update of the existing Chilean power supply system which has been remarkably influenced by new requirements the search for new energy supply sources has become a top priority.
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    Stochastic model for active distribution networks planning: An analysis of the combination of active network management schemes
    (2024) Lazo, Joaquin; Watts, David
    The widespread adoption of distributed generation (DG) is changing the operation of distribution networks. To increase the control of power flows and avoid the detriments of DG intermittency, active distribution networks (ADN) emerge as a feasible solution. In this paper, we propose a convex model for ADN expansion planning. Four active network management (ANM) schemes are considered: DG active power curtailment, DG reactive power control, on-load tap changer (OLTC) tap adjustment, and shunt compensation device control. The problem is formulated as a mixed integer second-order cone programming problem (MISOCP) using the distflow equations and second-order cone relaxations (SOCR). By scenario analysis, we address the uncertainty associated with power demand, renewable generation, and electricity prices. The proposed model is used to study the benefits of different combinations of ANM schemes to a modified IEEE 33-bus system and compare them with the individual benefits of each scheme. The results indicate that ANM schemes can reduce total network costs, reduce losses, delay network reinforcement, and improve the voltage profile. In addition, some combinations of schemes develop synergies in which the combined economic benefits are greater than the sum of the individual benefits.
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    The unnoticed impact of long-term cost information on wind farms' economic value in the USA. - A real option analysis
    (2019) Maeda, Mansaku; Watts, David
    Renewable energies are a natural replacement for conventional or fossil fuel energy generation. One of these sources, wind energy, has exhibited significant cost reductions during the last decades. Even though this historical cost reduction trend is well known in the industry and in the academia, information on this cost trend and volatility has been scarcely incorporated in previous works, thus a natural concern arises when assessing their influence on the economic valuation of wind farms.