SEGEM: a simulation approach for electric generation management

We present a modeling framework for a robust simulation of multiperiod hydrothermal power management and energy trading under uncertainty in generators availability, fuel procurement, transport and stock costs, exogenous water inflow at river basins and energy demand per subperiod at each time period of a given planning horizon. A deterministic treatment of the problem provides unsatisfactory results for medium term (1-2 years) planning horizon. We use a 2-stage scenario analysis based on a partial recourse approach, where the generation decision policy can be implemented for a given set of initial periods and the solution for the other periods does not need to be anticipated and, then, it depends on the scenario to occur. We have used an augmented Lagrangean decomposition scheme by dualizing the coupling constraints splitting control variables (fuel stock and stored water) for the last implementable period. We present computational results including different simulations of a Spanish generation subsystem composed of 87 thermal generators, 57 hydro plants and reservoirs, 7 fuel types and 5 time periods. 160 scenarios are simultaneously considered.