Economic effects of a high share of renewable energies on power systems

• Autores: Miriam Bueno Lorenzo
• Directores de la Tesis: Julio Usaola García (dir. tes.), Mª Ángeles Moreno López de Saá (dir. tes.)
• Lectura: En la Universidad Carlos III de Madrid ( España ) en 2014
• Idioma: inglés
• Tribunal Calificador de la Tesis: José Carpio Ibáñez (presid.), Juan Miguel Morales Gonzalez (secret.), Joao P.S Catalao (voc.)
• Materias:
  • Ciencias tecnológicas
    • Tecnología energética
      • Fuentes no convencionales de energía
• Enlaces
  • Tesis en acceso abierto en: e-Archivo
• Resumen

  • The aim of this thesis is to study the participation of renewable energies in the Spanish power system. For this purpose, two kind of studies have been developed in the present work. On the one hand, the first part of the work aims to assess the participation of wind energy producers in the Spanish electricity market. On the other hand, the overall effects of an increased installed capacity of renewable energies on the power system are evaluated. Due to the intermittent nature and the low predictability of wind power, the participation of this energy in the day-ahead market implies large deviations from the initial schedule, which leads to a cost that has to be borne by the wind farm owner. By means of short term wind power prediction programs, these losses may be reduced, and, if the market allows the possibility of updating previous bids at intraday markets, the total income of the wind power producers can be increased by a significant percent. The imbalance losses for a wind power producer are important, and may be reduced by strategic bidding. Then, a tool that maximizes the incomes of wind power producers in electricity markets is employed in this study. Through a stochastic process a strategic bidding algorithm is designed, which takes into account the variables involved in the process, namely wind power forecasts, daily, intraday and imbalance market prices. As these variables are not known in advance, their forecasts are necessary as input data of the strategic bidding tool. So, prediction tools are integrated in the optimization process, which forecast intraday and imbalance prices. Also a short-term wind power prediction program is included in the tool. The problem considered is the optimization of the bid to the Intraday Market, given a position in the Daily Market, and considering the uncertainties of the involved random variables. Moreover, a risk analysis is included in the results to study the e ect of several risk attitudes in both the incomes obtained by wind power producers and the errors incurred by them. Realistic results coming from both historical real data of production and forecasts, and a real-time simulation project will be presented in this work. Simulation results were evaluated for ten months in 2007 and 2010, leading to a thorough analysis of the different strategies applied. In consequence, this analysis will contribute to extract valuable conclusions with regard to the participation of wind energy producers in the Spanish electricity market. The increased share of renewable energies has changed both power system functioning and conventional plants operation. With regard to the latter, power plants using fuel have change their operation mode to accommodate to the variability and partial predictability of renewable energy sources. This fact increases the operation costs of the conventional plants. Besides, market prices behaviour will experience changes, such as the decrease of average prices and the increase of their variability. The positive e ects of an increased renewable installed capacity are also assessed. Furthermore, in countries with abundant solar resource, studying the effects of a higher share of renewable energy sources on the generation mix is necessary, including a high portion of photovoltaic and solar thermal energy in the generation portfolio. Therefore, a model of the concentrated solar power generators has been developed in this work. The results of the thermoelectric model supplies the annual production of this technology, which has been integrated in the generation schedule model. To analyse the impact of the future con guration of the generation mix on the power system, a model of unit commitment has been employed. It includes the characteristics and installed capacity of the generators using fuel and the estimation of the future production series of renewable energies. The results discussion contains an analysis of some relevant characteristics of the future power system behaviour, such as, daily market prices, yearly production by technology, capacity factors of the di erent technologies, wind spilled energy, ratio of demand coverage coming from renewable sources, hourly variation of the energy supplied by hydro, coal, and natural gas power plants, greenhouse emissions and operation costs. -------------------------------------