ISE - Comunicações em actas de encontros científicos internacionais
Permanent URI for this collection
Browse
Recent Submissions
- The Role of Demand and Vres Flexibility in Carbon-Neutral Power Systems: Insights from Portugal and Spain in Prospective 2050 ScenariosPublication . Algarvio, Hugo; Couto, António; Lopes, Fernando; Estanqueiro, Ana; Faia, Ricardo; Santos, Gabriel; Carvalho, Rui; Faria, Pedro; Vale, ZitaABSTRACT: The goal of a carbon-neutral society by 2050 is speeding up the integration of variable renewable energy sources (vRES) in European power systems. For the expected levels of vRES, the adaptation of the demand will be crucial to manage the stochastic behaviour of these technologies. This work evaluates the impact of four prospective 2050 energy mix scenarios in the Iberian electricity market. All scenarios consider near 100% vRES shares. Scenarios that incentivize demand flexibility (S2 and S4) result in the lowest wholesale prices and costs for society. Peak load reduction using demand response occurred in the two scenarios (S1 and S3) with low demand flexibility and high share of renewable generation. S3 is the most unstable leading to the higher wholesale prices. The results highlight that an equilibrium between demand flexibility and investments in the generation side is essential for reducing costs and ensuring stability.
- From Day-Ahead to a 6-Hour Period-Ahead Market Adapted to the Stochastic Behaviour of Variable Energy Renewable SourcesPublication . Couto, António; Algarvio, Hugo; Lopes, Fernando; Estanqueiro, Ana; Santos, Gabriel; Lezama, Fernando; Faia, Ricardo; Carvalho, Rui; Vale, ZitaABSTRACT: The existing electricity market design challenges the fair and competitive participation of variable renewable energy sources (vRES) due to their weather dependence and limited forecasting accuracy, especially for long-time horizons, as required in the day-ahead market (DAM). These challenges impact market clearing prices and create imbalances, leading to inefficiencies, such as market-splitting events. To enhance the market efficiency and fairness for vRES producers, this work proposes a period-ahead market (PAM) with a 6-hour rolling horizon instead of the traditional 24-hour DAM. A case study of the Iberian electricity market with 2030 energy mix scenarios for Portugal and Spain, demonstrates that, in PAM, vRES producers can reduce wind and solar power forecast errors by over 7 % and 4 %, respectively, when compared with DAM. This leads to a 2 % decrease in electricity prices and an annual reduction of marketsplitting events in 158 hours thus enhancing price harmonization between Portugal and Spain. Additionally, balancing prices also decreased in PAM benefiting the balance responsible parties. The findings highlight that PAM improves the market's efficiency, a key factor in the pathway for the decarbonization of power systems.
- Decarbonization Transition Pathways and Regional Trends: Insights from One Million StudiesPublication . Bento, Nuno; Alves, Tiago; Ribeiro, Ricardo; Fontes, MargaridaABSTRACT: As global temperatures near critical thresholds and emissions continue to rise, the urgency for strategic, accelerated decarbonization grows. Despite a vast climate mitigation literature, a systematic understanding of actionable pathways remains limited. Here, we apply artificial intelligence to analyze over one million scientific papers (2011–2021), generating a data-driven typology of six archetypal decarbonization pathways: Technology Breakthrough, Electrification of Uses, Integrated Policy, Decarbonization of Electricity, Demand Reduction & Co-benefits, and Land Use & Circularity. Regional patterns show Electrification of Uses prevailing in Europe (EU27), while Technology Breakthrough dominates in China, the US, and Japan. Increasing political and societal resistance to mitigation makes the strategic selection and combination of pathways even more critical. Our analysis highlights key synergies between pathways, the scientific competencies required to support them, and persistent gaps—particularly in Land Use and Circularity. We also compare current climate policy directions with the typology, revealing alignment gaps that may weaken policy effectiveness. This framework enables policymakers to better match strategies with regional capacities and research strengths, offering a more coherent approach to decarbonization. Strengthening the integration of science, technology, and policy is essential to overcome fragmentation and deliver the emissions reductions needed to meet the net-zero climate targets.
- Driving Transformative Change: Assessing the Direction and Design of Decarbonization Policies in the EU, US, China, and JapanPublication . Fontes, Margarida; Sousa, Cristina; Bento, NunoABSTRACT: The transition to low‐carbon economies demands policies that drive both decarbonization and deep socioeconomic transformation. This paper assesses the “transformative potential” of 3,400 decarbonization policies from Europe, the US, China, and Japan. We define transformative potential considering both policy direction – alignment with sustainability goals, and policy design ‐ presence of mechanisms that can induce transformation, such as experimentation, actor diversity, multiscale coordination, and reflexivity. The research shows that when we consider a broad universe of decarbonization policies, transformative potential is still limited: only 20% of policies align with at least one transition pathway and include at least one transformative mechanism; and just 2% include three or more mechanisms. By identifying distinguishing features of these higher transformative potential policies, the paper contributes to understanding how technological, sectoral and contextual factors shape the capacity of policies to enable transformative change.
- A Methodology for Dynamic Procurement of Secondary Reserve Capacity in Power Systems with Significant vRES PenetrationsPublication . Algarvio, Hugo; Couto, António; Estanqueiro, AnaABSTRACT: The European pathway to carbon neutrality indicates strong investments in variable renewable energy sources. Demand-side and variable renewable players rely on forecasts to participate in day-ahead markets closing between 12 and 37 hours ahead of real-time operation. As such, the further from the real-time operation those forecasts are provided, the higher their errors and the uncertainty. Deviations from the market schedules are balanced using real-time reserves. Traditionally, transmission system operators (TSOs) use a symmetrical procurement of up and down reserves based on the expected demand. This work considers the computation of a dynamic up and down procurement of secondary capacities by considering the expected deviations, using the day-ahead programmed and expected dispatches of variable renewables, demand, other technologies, and the cross-border capacities. The study uses operational open data from the Spanish TSO from 2019 to 2022. The proposed methodology allows increasing the usage of the up and down secondary capacities by almost 13% and 8%, respectively, freeing up 11% of the allocated resources, on average.
- A Double Pricing and Penalties “Separated” Imbalance Settlement Mechanism to Incentive Self Balancing of Market PartiesPublication . Algarvio, Hugo; Couto, António; Estanqueiro, AnaABSTRACT: Increasing penetrations of variable renewable energy sources increase the usage and costs of reserves due to their stochastic nature. As Balance Responsible Parties all market participants pay the balancing costs of their imbalances according to the imbalance settlement mechanism of each market zone. The European balancing markets and the imbalance settlement mechanisms still have different rules across Europe, but normally, the prices of upward and downward regulation are higher and lower than spot prices, respectively, originating penalties. Against this background, this work presents an alternative “Separated” imbalance settlement mechanism that consists of unbalanced parties paying/receiving directly the costs/revenues of the balancing markets needed to balance them. In this mechanism, the net costs/revenues of Transmission System Operators with energy balancing mechanisms are zero. Furthermore, by separating the payment of penalties between unbalanced directions, this mechanism also incentive unbalanced parties to self-control their dispatch, mitigating part of their deviations. Two case studies have been presented to test the application of this mechanism in Portugal and Spain, comparing its outputs with those of the mechanisms in place in these countries during 2019. Outputs from the studies prove the benefit of using this mechanism to reduce penalties, mainly in the case of active market players that can partly control their dispatch.
- Reduction of the Market Splitting Occurrences: A Dynamic Line Rating Approach for the 2030 Iberian Day-ahead Market ScenariosPublication . Algarvio, Hugo; Couto, António; Estanqueiro, Ana; Carvalho, Rui; Santos, Gabriel; Faia, Ricardo; Faria, Pedro; Vale, ZitaABSTRACT: Typically, Transmission System Operators apply power flow models with Seasonal Line Rating prescriptions to compute the ampacity of power lines, in a process that enables to obtain the cross-border capacity for trading between different countries or market zones. These seasonal-dependent models rely on fixed conservative meteorological conditions throughout the year, underestimating the real-time transmission capacity of overhead lines. This can contribute to market splitting occurrences, i.e., a situation where the cleared power flow between different market zones of the coupled market is superior to the cross-border capacity, separating markets, which brings economic losses to market participants. Dynamic Line Rating analysis allows computing the overhead lines’ capacity considering the weather conditions that influence the power line's thermal dynamics. This work presents a study that applies the CIGRÉ 601 model in cross-border power lines between Portugal and Spain to quantify the reduction in market splitting occurrences in the day-ahead Iberian market considering based on the installed capacities from the 2030 national energy and climate plans. Comparing with the seasonal approach, dynamic line rating enabled to reduce the number of market splitting occurrences from 1512 to 514, reducing the electricity costs by more than 1% and the price difference from 19 to 12 €/MWh.
- Descarbonizar micro/mini-redes através da complementaridade da produção solar fotovoltaica e eólicaPublication . Couto, António; Cardoso, João P.; Simões, Teresa; Estanqueiro, Ana; Stevanato, N.; Mereu, R.RESUMO: Este trabalho apresenta uma metodologia para determinar a capacidade instalada ótima de fontes de energia renováveis variáveis no tempo, numa mini-rede selecionada, e avaliar o potencial destas tecnologias para satisfazer o consumo de eletricidade, permitindo reduzir a dependência de geradores alimentados por combustíveis fósseis. A capacidade ótima é identificada com base na exploração estratégica da sinergia eólica e solar fotovoltaica (FV) para atender à procura de eletricidade, neste caso, para substituir a produção com geradores a diesel. Para este efeito, neste trabalho, explora-se o uso de diferentes ângulos de azimute e inclinação dos sistemas solares fotovoltaicos fixos (convencionais e bifaciais), bem como sistemas com seguimento para criar um portfólio de geração ideal. Os resultados preliminares obtidos destacam que é necessário diversificar a orientação dos painéis solares e explorar a energia eólica para evitar vários períodos com excesso de produção e, consequentemente, corte de geração. Apesar de ser necessário continuar a desenvolver este trabalho, os resultados mostram que o uso dos geradores a diesel pode ser significativamente reduzido, especialmente durante o período diurno.
- How innovations lead to structural change: Elements for a theory of system transformationPublication . Bento, Nuno; Fontes, Margarida; Costa, EvaldoABSTRACT: Accelerating decarbonization to limit global warming to 1.5ºC requires a deep change in the provision and consumption of essential services such as mobility, thermal comfort or substance. It involves the dissemination of several social, technological and institutional innovations across multiple sectors. This contrasts with the traditional perspective in the literature that focuses on specific innovations in a single sector (e.g., solar PV in electricity generation). This research examines the conditions and processes that enable system transformation, here defined as a structural change which have wide social and economic impacts on several sectors (energy, transport, building, industry, food). Building on theories and concepts from economics, innovation and technological change, and sustainability transitions, four main conditions for system transformation emerge: technology; business model; social acceptance; institutions. These conditions underpin processes of system transformation that can be led by demand, supply or coordination. The analysis of two empirical examples (digital convergence and sharing economy) illustrates the explanatory power of this framework and offers insights for improving both the theory and the strategies for deep decarbonization.
- Transformative mechanisms in decarbonization policies: a structured approachPublication . Sousa, Cristina; Fontes, Margarida; Bento, NunoABSTRACT: The transition to a low-carbon society should accelerate to avoid an increase in the temperatures above 1.5º to 2ºC, and this is unlikely to occur without policy intervention (IPCC, 2022). Given the complexity of the problem, recent debates have increasingly pointed to the need of adopting a new, broader view on policy intervention (Weber and Rohracher, 2012; Hekkert et al., 2020). This entails a move beyond a single focus on economic competitiveness and growth and towards a focus on societal problems or “grand challenges”, leading to the emergence of the concept of transformative innovation policy (Schot and Steinmueller 2018; Dierks et al., 2019). This new rationale implies the consideration of a much broader range of policy objectives, targets and instruments, as well as the notion that a mix of policies needs to be deployed to achieve the desired goals (Rogge and Reichardt, 2016).