Besides the established electricity markets, power plant operators have nowadays the chance to market their generation capacities at reserve markets. In addition to day-ahead markets, i.e. the spot market for electrical energy and the market for minute reserve, power plant operators have the opportunity to participate in intraday markets, which become more and more significant. Another degree of freedom for power plant operators is the dispatch of the reserve energy requested by the transmission system operator on available generation units. The dispatch of the remaining reserve power that has to be provided as well as the opportunity to start up (quick start) units are further degrees of freedom in the intraday operation of power plants. In this paper a method is described that takes advantage of these intraday optimization potentials under consideration of planning uncertainties, e.g. the amount of requested reserve energy, to determine the optimal intraday operation strategy.