As a benchmark exercise for testing software and methods developed in Hycon2 for decen- tralized and distributed control, we address the problem of designing the Automatic Genera- tion Control (AGC) layer in power network systems. In particular, we present three different scenarios and discuss performance levels that can be reached using Centralized Model Predic- tive Control (MPC). These results can be used as a milestone for comparing the performance of alternative control schemes. Matlab software for simulating the scenarios is also provided in an accompanying file.