A method for solving a probabilistic power flow that deals with the uncertainties of (i) wind generation, (ii) load and (iii) generation availability in power systems is proposed. Dependence between random variables has been considered. The method is based on the properties of cumulants of random variables. Cornish-Fisher expansion series are used to obtain the cumulative distribution function (CDF) of the output variables. Multimodal CDF are obtained by convolutions, whose number has been minimised in order to decrease the computation requirements.

In this paper, a preliminary analysis of the impact of high wind power penetration in the planning and operation of the Spanish power system is presented. The problems studied in the paper are those related to the stability of the power system. This key subject could be deeply influenced by the installation of up to 15000 MW of wind power generation as it has been planned for the next six years. The analysis presented here is based on the results of dynamic simulations. Dynamic models of the induction generator (squirrel cage and doubly fed) and models of the wind farms have been developed to make possible the simulations. From the simulation results some conclusions and recommendations have been extracted, which would contribute to the appropriate integration of the new wind generation foreseen for the Spanish power system.

Concentrating solar power (CSP) is a promising technology, which will most likely develop in some parts of the world in the near future. It is already being exploited in certain countries, such as the USA and Spain, where subsidy policies are granted to support its development. One advantage of this technology is the possibility of storing the received thermal energy, and using it later. This storage allows CSP plants to smooth the electricity production and to schedule it independently of the instantaneous solar resource. In this way, these plants may be considered as dispatchable, and therefore they can be more easily and efficiently integrated into the power grid. In an electricity market, this means fitting the production as much as possible to the spot price, which sets the system needs of energy. In this way, shifting part of its production to hours with more demand and higher prices maximises the revenues of the plant. This study proposes an optimisation method that aims to maximise CSP plant revenues by taking into account daily electricity prices. The model is independent of the technology used. The performed simulation cases with this model show that current Spanish subsidy policies reduce the incentive for the full use of CSP plant dispatchability.