Comparative life cycle assessment of an innovative CSP air-cooled system and conventional condensers

In this paper, a first prototype of the innovative modular air-cooled condenser (MACC) proposed under the EU-funded MACCSol research project (Development and verification of a novel modular air cooled condenser for enhanced concentrated solar power generation) is compared with a water-cooled condenser (WCC) and an air-cooled condenser (ACC) in a reference concentrated solar power (CSP) plant. The aim is to evaluate the complete environmental profile of each cooling option and to highlight the differences in terms of impacts. The life cycle assessment (LCA) methodology is being used in order to evaluate the life cycle impacts of the three condensers. Firstly, the life cycle impacts are evaluated through the most used methods International Panel on Climate Change (IPCC) 2007 and Ecoindicator 99, using the SimaPro 7.3 software. Secondly, the Ecological Scarcity 2006 approach is used, since it takes into account the main issue of CSP plants: freshwater consumption. Results show that the impact of the MACC is comparable with the ACC one and, in particular, it results quite lower according to all the methods used. Evaluating the severity of local impact through the Ecological Scarcity 2006 method, since the site of operation of the condensers is characterized by medium water stress conditions, the WCC is the cooling option with the highest impact. The best cooling solution, instead, is represented by the MACC: its impact, in fact, results halved compared to WCC. The impact of MACC results significantly affected by the transport activity; therefore, the choice of the transport modes represents a key issue to optimize its life cycle impact. The LCA analysis carried out definitely shows that the MACC condenser represents a valid alternative to the conventional cooling solutions in regions suitable for CSP plants. In particular, the environmental benefits achievable with the MACC result more evident with the increase of the direct normal irradiance (DNI). The transport activity planning resulted a key issue to further optimize the MACC life cycle impact.