Innovative Applications of O.R.Stochastic short-term hydropower planning with inflow scenario trees

- A scenario tree generation method is proposed.
- A stochastic short-term unit commitment and loading problem is modeled.
- Scenario tree method produces more energy than median scenario.
- Computational time to generate trees and optimize is very fast.

This paper presents an optimization approach to solve the short-term hydropower unit commitment and loading problem with uncertain inflows. A scenario tree is built based on a forecasted fan of inflows, which is developed using the weather forecast and the historical weather realizations. The tree-building approach seeks to minimize the nested distance between the stochastic process of historical inflow data and the multistage stochastic process represented in the scenario tree. A two-phase multistage stochastic model is used to solve the problem. The proposed approach is tested on a 31 day rolling-horizon with daily forecasted inflows for three power plants situated in the province of Quebec, Canada, that belong to the company Rio Tinto.