3 Presentations

• 
  10:30 AM - 10:55 AM

  An effective neighborhood search for short-term planning of large-scale hydropower systems

  • Alexia Marchand, presenter, Polytechnique Montréal
  • Michel Gendreau, Polytechnique Montréal
  • Marko Blais, Hydro-Québec
  • Grégory Émiel, Hydro-Québec

  Short-term hydro-generation scheduling aims at minimizing the energy consumption for the next 7 to 15 days on an hourly basis, while satisfying the electrical load as well as operational, regulatory and safety requirements, such as dams safety, grid operations, electrical reliability, units start-ups and shut-downs, flood control, environmental, recreational and maintenance constraints. In an ever-changing environment, planners need to take decisions quickly and often adapt their schedules to new conditions. They need a tool that is fast, reactive, and flexible.

  We present an effective neighborhood search with new neighborhood structures that quickly provides near-optimal solutions for short-term planning of Hydro-Québec’s production system, one of the largest in the world. It can handle multi-objective problems, non-linear and non-convex constraints, as well as unfeasible solutions. We give numerical results on real instances of Hydro-Québec that also consider the wind and small hydro-generation plants.

• 
  10:55 AM - 11:20 AM

  Numerical methods for solving mid-term hydropower optimization with stochastic dynamic programming

  • Kenjy Demeester, presenter,
  • Pascal Côté, Rio Tinto
  • Dominique Orban, GERAD - Polytechnique Montréal

  In this talk, we present new strategies to reduce the computation time required to optimize hydropower systems management with stochastic dynamic programming (SDP). In the SDP algorithm, the original problem is decomposed as a sequence of small scale nonlinear subproblems. Based on the concavity of the hydropower production functions, which can be accurately estimated by linear approximation, we demonstrate the benefits of using a successive linear programming (SLP) algorithm. We compare the SLP algorithm with other state-of-the-art nonlinear optimization solvers and the numerical results show that the computation time can be reduced significantly without loss of accuracy.

• 
  11:20 AM - 11:45 AM

  Scheduling generator maintenance outages in hydropower systems

  • Jesus Rodriguez, presenter, HEC Montreal
  • Miguel F. Anjos, GERAD, Polytechnique Montréal
  • Guy Desaulniers, GERAD - Polytechnique Montréal
  • Pascal Côté, Rio Tinto

  In the power industry, maintenance of generators is essential for the economic and reliable system operation. Particularly in hydroelectric systems, scheduling of maintenance outages is affected by non-linearities of the power production function and uncertain water inflows. In this talk we present model formulations and solution approaches for this problem.