An integrated energetic evaluation has been performed of a reference coal-fired power plant, a power plant with an advanced MEA-based post-combustion CO₂ capture plant, and a power plant with a capture plant using concentrated piperazine (PZ) and high-pressure flash regeneration. This comparison shows that using a MEA-based capture plant reduces the net electric efficiency from 44.6% to 35.5%, while the PZ-based capture plant reduces it to 37.4%, corresponding to an efficiency penalty of only 7.2%.