The energy sector witnesses major structural challenges due to EU liberalization of energy markets and the changeover to renewable energy sources. In order to meet these challenges, large investments are necessary which of course should be as cost-effective as possible. Moreover, the new regulation rules lead to more complex and involved planning and operation processes, so existing methods are no longer appropriate. The goal of this working group is the development of novel mathematical models and solutions methods capable to cope with this increasing complexity.

Energy optimization problems are often, due to their underlying technical and physical processes, nonlinear and nonconvex, and some of the control decisions are of discrete nature. An appropriate mathematical modelling leads to large mixed-integer nonconvex problems, which usually cannot be solved by standard solvers. Typically, there is also uncertainty regarding supply and demand that has to be taken into account. Moreover, the behavior of other market participants may also have an impact. Therefore, models feature both stochastic and game-theoretic components.

Due to the inherent mathematical difficulties, effective mathematical solution methods have to be custom-tailored to the problems to be solved. Currently, we are developing such methods for the capacity and expansion planning for Germany's gas transmission network. To this end, we are closely collaborating with partners from gas industry, the German Federal Network Agency, and several other research institutes.