  The energy sector is facing rapid changes in the transition towards clean
renewable sources. However, the growing share of volatile, fluctuating
renewable generation such as wind or solar energy has already led to an
increase in power grid congestion and network security concerns. Grid operators
mitigate these by modifying either generation or demand (redispatching,
curtailment, flexible loads). Unfortunately, redispatching of fossil generators
leads to excessive grid operation costs and higher emissions, which is in
direct opposition to the decarbonization of the energy sector. In this paper,
we propose an AlphaZero-based grid topology optimization agent as a non-costly,
carbon-free congestion management alternative. Our experimental evaluation
confirms the potential of topology optimization for power grid operation,
achieves a reduction of the average amount of required redispatching by 60%,
and shows the interoperability with traditional congestion management methods.
Our approach also ranked 1st in the WCCI 2022 Learning to Run a Power Network
(L2RPN) competition. Based on our findings, we identify and discuss open
research problems as well as technical challenges for a productive system on a
real power grid.
