HiPerCap aims to develop high-potential novel and environmentally benign technologies and processes for post-combustion CO₂ capture leading to real breakthroughs. The project includes all the main separation categories for post-combustion CO₂ capture, absorption, adsorption and membranes. Each technology category is focused on several promising concepts and a key focus in the project is to demonstrate the potential of these various capture technologies. A methodology has been developed for assessment and fair comparison of the various technologies and benchmarking against a state-of-the art capture technology demonstrated in the CESAR project. In the present paper, this methodology is demonstrated for two of the absorption-based concepts involving precipitating solvent systems. Here, the assessment is based on energy efficiency penalty for the total integrated power plant and capture plant process. Though there is a slight improvement compared to the reference plant (0.5 and 7%, respectively) neither of the two precipitating solvent systems assessed here meet the project target of 25% improvement. However, the uncertainty level in the numbers is higher for these two systems compared to the reference case and the models used for the capture process should be improved before a conclusion can be made. The HiPerCap project is just starting the assessment phase and it must be emphasized that additional assessment criteria will be used and other types of technologies will be assessed before completion at the end of 2017.

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%.

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%.