Environmental and Economic Life Cycle assessment of a BIPV system installed in a university campus in Mendoza (Argentina).

ARENA, A. P.

Palermo

Conferencia; 13th Conference on Sustainable Development of Energy, Water and Environment Systems - SDEWES Conference; 2018

University of Zagreb, Zagreb, Croatia University of Palermo, Palermo, Italy Instituto Superior Técnico, Lisbon, Portugal

Distributed PV generation can help tackling many environmental concerns of society: the depletion of non-renewable energy sources, climate change, urban pollution, etc.However, the economic and environmental benefits of these technologies are dependent on many variables, and it is not always certain whether the system will produce positive results. In this study a Building Integrated Photovoltaic (BIPV) system installed in a university campus in Mendoza is presented and evaluated from these points of view.The system is made up of 12 PV panels which have been installed as overhangs, thus blocking the solar radiation before entering the classrooms during the hot periods of the year, and transforming it into electricity.The economic assessment of the BIPV system is performed using Life Cycle Costing (LCC), considering initial investment and future replacement and maintenance costs, as well as the economic benefits of electricity generation. The economic aspect of the shading effect of the system has been assessed considering the avoided costs of acquisition, installation, replacement and maintenance of an alternative sunshade. In order to properly handle sensitive variables such as discount rate, energy costs and projections of future electricity increase rates different scenarios have been considered.Life Cycle Assessment was used for the evaluation of the environmental aspects of the system. The double function of the BIPV system has been handled following the boundaries expansion approach. The impact assessment stage was performed using indicators for cumulative energy demand and Global warming potential.Results show that current economic conditions are not attractive for the implementation of PV systems in the residential sector of the country, despite the sharp decrease of PV panel costs. The payback period is beyond the expected useful life of the PV system, even when a zero discount rate is considered. However, the strategy of integration of the PV system as an overhang is enough to overcome the economic deficit of the system.From the environmental point of view the results are very encouraging in every impact category compared with the displaced electricity. GWP is 97.3 gCO2eq/kWh which is about one fifth of the Argentinean average emission factor. The energy payback period (EPBP) is reached in 9 years. When the double function is taken into account, GWP is only 55 gCO2eq/kWh, while EPBP is reached in only 5.2 years.