The objective of this paper is to assess an economic dispatch considering a power system portfolio, which includes predominant amount of hydro power and increasing quantities of intermittent renewables in relation to the total electric capacity. With growing importance of intermittent wind and solar generation taking part into power systems worldwide, there is need for greater chronological resolution to estimate the flexibility of the power system to offer firm capacity. In this way, a linear optimization model operating hourly is developed to calculate the minimum power system cost, while stablishing the capacity allocation to meet the projected load throughout one-year simulation, as an estimation of how the hourly economic dispatch impacts the scheduling of generators belonging to a power system with this portfolio composition. A central focus is how to operate the available hydro capacity to back up intermittent renewables, evaluating the physical hydro operating constraints, monthly energy balance and maximum power availability. A case study was simulated based on the Brazil’s power system configuration, showing that existing hydro capacity provide hourly flexibility to back-up intermittent renewables, potentially saving 1.2 Billion R$, about 3.6% of total system cost referred to 2019. It is worthwhile to realize that the developed methodology can be employed to other power systems with similar capacity portfolio structure for the purpose of calculating its optimum allocation for a specified region and target year.
KeywordsEconomic DispatchEnergy PlanningOperation FlexibilityPower SystemTransmission SystemVariable Renewable Energy
JISEA (Joint Institute for Strategic Energy Analysis) (2020) Options for Resilient and Flexible Power Systems in Select South America Economies. Joint Institute for Strategic Energy Analysis, Denver. https://www.nrel.gov/docs/fy20osti/75431.pdf
Ebert, P.S. and Sperandio, M. (2018) Influence of Wind Power Integration on the Planning and Operation of Hydrothermal Systems Using System Dynamics. IEEE Latin America Transactions, 16, 1432-1438. https://doi.org/10.1109/TLA.2018.8408438
Correa, C., Sanchez, A. and Marulanda, G. (2016) Expansion of Transmission Networks Considering Large Wind Power Penetration and Demand Uncertainty. IEEE Latin America Transactions, 14, 1235-1244. https://doi.org/10.1109/TLA.2016.7459604
Tapia-Ahumada, K.D. (2021) EleMod: A Model for Capacity Expansion Planning, Hourly Operation and Economic Dispatch in Electric Power Systems with Intermittent Renewable Generation. Joint Program on the Science and Policy of Global Change, Technical Note TN#19, Massachusetts Institute of Technology, Cambridge.
Perez-Arriaga, I.J. and Meseguer, C. (1997) Wholesale Marginal Prices in Competitive Generation Markets. IEEE Transactions on Power Systems, 12, 710-717. https://doi.org/10.1109/59.589661
EPE (Empresa de Pesquisa Energética) (2020) Plano decenal de energia 2029. http://www.epe.gov.br/pde/Paginas/default.aspx
Welfle, A. (2017) Balancing Growing Global Bioenergy Resource Demands—Brazil’s Biomass Potential and the Availability of Resource for Trade. Biomass and Bioenergy, 105, 83-95. https://doi.org/10.1016/j.biombioe.2017.06.011
Auer, H. and Haas, R. (2016) On Integrating Large Shares of Variable Renewables into the Electricity System. Energy, 115, 1592-1601. https://doi.org/10.1016/j.energy.2016.05.067
Koltsaklis, N.E., Dagoumas, A.S. and Panapakidis, I.P. (2017) Impact of the Penetration of Renewables on Flexibility Need. Energy Policy, 109, 360-369. https://doi.org/10.1016/j.enpol.2017.07.026
Bejerano, J.B. and Baute, E.T. (2016) Impacts of Intermittent Renewable Generation on Electricity Costs. Energy Policy, 94, 411-420. https://doi.org/10.1016/j.enpol.2015.10.024
Stram, B.N. (2016) Key Challenges to Expanding Renewable Energy. Energy Policy, 96, 728-734. https://doi.org/10.1016/j.enpol.2016.05.034
Salles, M.B.C. (2015) The Power of the Brazilian Wind. Revista, Harvard University, Cambridge, 15, 38.
Abdel-Karim, N., Preston, E., Moura, J. and Coleman, T. (2017) Variable Energy Resource Capacity Contributions Consistent with Reserve Margin and Reliability. 2017 IEEE Power & Energy Society General Meeting, Chicago, 16-20 July 2017, 1-5. https://doi.org/10.1109/PESGM.2017.8274569
Herrera, B. and Watts, D. (2012) The Capacity Value of Wind: Foundations, Review and Applications in Chile. IEEE Latin America Transactions, 10, 1574-1580. https://doi.org/10.1109/TLA.2012.6187601
Ramos, D.S., Guarnier, E. and Witzler, L.T. (2012) Using the Seasonal Diversity between Renewable Energy Sources to Mitigate the Effects of Wind Generation Uncertainties. 2012 6th IEEE/PES Transmission and Distribution: Latin America Conference and Exposition (T&D-LA), Montevideo, 3-5 September 2012, 1-7. https://doi.org/10.1109/TDC-LA.2012.6319142
Mummey, J.F.C., Soares Ramos, D., Sauer, I.L. and Yeh, W.G. (2019) Important Issues and Results When Considering the Stochastic Representation of Wind Power Plants in a Generation Optimization Model: An Application to the Large Brazilian Interconnected Power System. Energy and Power Engineering, 11, 320-332. https://doi.org/10.4236/epe.2019.118020
Witzler, L.T., Ramos, D.S., Camargo, L.A.S. and Guarnier, E. (2016) Reconstruction of Wind Generation Historical Series Aiming at the Analysis of Energy Complementarity: Methodology and Applications. 2016 13th International Conference on the European Energy Market (EEM), Porto, 6-9 June 2016, 1-6. https://doi.org/10.1109/EEM.2016.7521324
Mummey, J.F.C. (2017) Uma contribuicao metodológica para a otimizacao da operacao e expansao do sistema hidrotérmico brasileiro mediante a representacao estocástica da geracao eólica. Tese de Doutorado, Instituto de Energia e Ambiente da Universidade de Sao Paulo, Sao Paulo.
Araújo, P. and Marinho M. (2019) Analysis of Hydro-Wind Complementarity in State of Pernambuco, Brazil by Means of Weibull Parameters. IEEE Latin America Transactions, 17, 556-563. https://doi.org/10.1109/TLA.2019.8891879
Susteras, G.L., Ramos, D.S., Chaves, J.R.A. and Susteras, A.C.V.J. (2011) Attracting Wind Generators to the Wholesale Market by Mitigating Individual Exposure to Intermittent Outputs: An Adaptation of the Brazilian Experience with Hydro Generation. 8th International Conference on the European Energy Market, Zagreb, 25-27 May 2011, 674-679. https://doi.org/10.1109/EEM.2011.5953096
CRESESB (Centro de Referencia em Energias Solar e Eólica Sérgio de S. Brito) (2020) Potencial energetic. http://www.cresesb.cepel.br/
CEPEL (Centro de Pesquisas de Energia Elétrica) Otimizacao Energética e Meio Ambiente. http://www.cepel.br/linhas-de-pesquisa/newave/
Navarro, P.R. (2014) Water Cost in Electricity Generation: Short Term Operation Planning. 2014 IEEE PES General Meeting, National Harbor, 27-31 July 2014, 1-5. https://doi.org/10.1109/PESGM.2014.6939077
Celebi, M.E., Kingravi, H.A. and Vela, P.A. (2013) A Comparative Study of Efficient Initialization Methods for the K-Means Clustering Algorithm. Experts Systems with Applications, 40, 200-210. https://doi.org/10.1016/j.eswa.2012.07.021
ONS (Operador Nacional do Sistema Elétrico) Resultados da operacao-histórico da operacao/geracao de energia. http://www.ons.org.br/Paginas/resultadosdaoperacao/historico-daoperacao/curva_carga_horaria.aspx
Marques, T.C., Cicogna, M.A. and Soares, S. (2006) Benefits of Coordination in the Operation of Hydroelectric Power Systems: Brazilian Case. 2006 IEEE Power Engineering Society Meeting, Montreal, 18-22 June 2006, 8. https://doi.org/10.1109/PES.2006.1709574
CEPEL (Centro de Pesquisas de Energia Elétrica) Planejamento da operacao energética-programas computacionais NEWAVE e DECOMP. http://www.cepel.br/produtos/programas-computacionais/planejamento-da-operacao-energetica.htm
Pereira, M.V.F. and Pinto, L.M.V.G. (1985) Stochastic Optimization of Multireservoir Hydroelectric System: A Decomposition Approach. Water Resources Research, 21, 779-792. https://doi.org/10.1029/WR021i006p00779
Zambelli, M., Filho, S.S., Toscano, A.E., dos Santos, E. and da Silva Filho, D. (2011) NEWAVE versus ODIN: Comparison of Stochastic and Deterministic Models for the Long-Term Hydropower Scheduling of the Interconnected Brazilian System. Sba: Controle and Automacao Sociedade Brasileira de Automática, 22, 598-609. https://doi.org/10.1590/S0103-17592011000600005
Luiz Diniz, A., Da Serra Costa, F., Elvira Maceira, M., Norbiato dos Santos, T., Dos Santos, L.C.B. and Neves Cabral, R. (2018) Short/Mid-Term Hydrothermal Dispatch and Spot Pricing for Large-Scale Systems—The Case of Brazil. 2018 Power Systems Computation Conference (PSCC), Dublin, 11-15 June 2018, 1-7. https://doi.org/10.23919/PSCC.2018.8442897
Diniz, A. and Souza, T. (2015) Short-Term Hydrothermal Dispatch with River-Level and Routing Constraints. 2015 IEEE Power & Energy Society General Meeting, Denver, 26-30 July 2015, 1. https://doi.org/10.1109/PESGM.2015.7285658
Barroso, L.A., Pereira, M.V. and Rosenblatt, J. (2003) Ensuring Energy Supply Adequacy in Market-Based Systems: The Brazilian Experience. 2003 IEEE Power Engineering Society General Meeting (IEEE Cat. No.03CH37491), Vol. 1, Toronto, 13-17 July 2003, 529-531. https://doi.org/10.1109/PES.2003.1267236