Dynamic Parametric LCA of BIPV Design

Abstract

The Building Integrated Photovoltaics is considered as a promising renewable technology for building on-site energy production. While the electricity produced by BIPV varies according to the weather condition, the grid mix alters in terms of the generation methods. Different generation technology differs in carbon intensity and primary energy intensity widely which results in the variation of the environmental impacts of the electricity supply accordingly. Current static method in calculation of the energy and carbon payback time of BIPV applies annual average factors which can potentially lead to lower estimations of the carbon and energy payback time periods.

This master thesis aims at improving the evaluation of the potential environmental impacts of different BIPV designs by applying dynamic method which uses hourly grid mix factors instead of annual averages and providing a parametric evaluation toolset that can be integrated into early architecture design stages.

Two case studies are demonstrated in this thesis to compare the results of the static and dynamic methods in the Swiss context. Results show that the static method can underestimate the carbon payback time up to about 33%, 6.3% for the primary energy payback time, and up to 11% for the non-renewable primary energy under the current Swiss mix. A simple sensitivity analysis is performed on the MFH Solaris project. Results show that the relative difference between these two methods is determined mostly by the orientation of the BIPV panels, and the variation of the Swiss mix. A simplified scenario is developed based on the learning curve of PV technology, current information on grid mix and the emission targets established by Switzerland and the neighbor counties such as France and Germany. The analysis result shows the BIPV technology is still a promising for decarbonization under a greener electricity mix if the embodied impact can decrease as predicted.