In this new work submitted to the journal IEEE Transactions on Power Systems, the authors, prof. F.-Javier Heredia, Dr. Marcos.-J Rider and Ms. Cristina Corchero developed, within the general stochastic programming framework, a new optimal bid model for both thermal and generic programmingn units (also known as Virtual Powewr Plants) taken into account the most recent regulation rules of the Spanish peninsular system MIBEL. This model allows a price-taker generation company to decide the unit commitment and sale bids of the thermal units, the optimal sale/purchase bids of the Virtual Power Plant and the economic dispatch of the bilateral contracts between all the programming units (thermal and generic). Download the full text at http://hdl.handle.net/2117/2282