Extensive research efforts have been applied to obtain more efficient and less cost-intensive absorption-based processes and solvent systems for CO₂capture during the last 15-20 years. High concentratedaqueous solutions of piperazine (PZ) have been suggested as a good replacement for the current bench-mark solvent mono-ethanolamine (MEA). So far, the research on concentrated PZ solutions has mainlyfocused on the development and evaluation of various configurations for the post-combustion CO₂cap-ture process. The present paper studies the integration of a configuration based on high-pressure flashregeneration with the upstream power plant. The main focus is on the overall energy performance, but aqualitative analysis of the effect of flexible operation is added as this is important for the optimization ofthe total plant. A power plant integrated with the optimal PZ-based capture plant is found to have a netelectric efficiency of 37.4%, which is 7.2% less than the reference power plant without CO₂capture. Theefficiency penalty when using an MEA-based capture plant including lean-vapour compression is 9.1%.