  The paper develops a typical management problem of a large power producer
(i.e., he can partly influence the market price). In particular, he routinely
needs to decide how much of his generation it is preferable to commit to fixed
price bilateral contracts (e.g., futures) or to the spot market. However, he
also needs to plan how to distribute the production across the different plants
under his control. The two decisions, namely the sales-mix and the generation
plan, naturally interact, since the opportunity to influence the spot price
depends, among other things, by the amount of the energy that the producer
directs on the spot market. We develop a risk management problem, since we
consider an optimization problem combining a trade-off between expectation and
conditional value at risk of the profit function of the producer. The sources
of uncertainty are relatively large and encompass demand, renewables generation
and the fuel costs of conventional plants. We also model endogenously the price
of futures in a way reflecting an information advantage of a large power
producer. In particular, it is assumed that the market forecast the price of
futures in a naive way, namely not anticipating the impact of the large
producer on the spot market. The paper provides a MILP formulation of the
problem, and it analyzes the solution through a simulation based on Spanish
power market data.
