Impact of Modelling Details on the Generation Function for a Norwegian Hydropower Producer

Abstract

In the following work the generation function relating water discharge to power output for a hydropower station is considered. The conventional approach to modelling the generation function has been to simplify it as a concave function. In the future it is expected that the stations will operate at more varied power outputs, motivating the need for a more detailed modelling of the generation function. Therefore, an investigation on how the nonconcave generation function may be simplified, without having to lose the function's inherent geometric shape, is performed. A greedy algorithm and a Minimum Least Square Error (MLSE) approach is used. It was found that the function can be reduced until a point where the changes become too prominent. A benchmark test against the conventional modelling approach found that it is important with a detailed modelling of the generation function when environmental constraints, such as minimum discharge, are included.