The appropriate selection of the condenser pressure, apart from raising the live steam parameters, is a factor which could have a decisive impact on the improvement in the efficiency of the thermal cycle. The pressure value depends both on the parameters and configuration of the cooling system. The condenser cooling system configuration is particularly important in the case of newly designed high-capacity ultra-supercritical power plants. The presented study comprises a comparison of two variants of a cooling system for a 900 MW ultra-supercritical power unit. The serial and parallel configurations of the condenser are considered. A thermodynamic analysis which takes account of the exhaust loss of the LP turbine is performed. Additionally, an economic analysis based on the NPV method is conducted for all investigated cases. (C) 2013 Elsevier Ltd. All rights reserved.