Reducing environmental impacts through a smart design of microgrids: Life Cycle Assessment for AC and DC

Abstract

Microgrids with integrated renewable energies have revealed promising potential to be a reliable, efficient, and clean key element for smart grid concepts. Further efficiency and reliability improvements might be achieved when the microgrid is operated with a direct current instead of an alternating current distribution. For a holistic assessment, the environmental impacts of this potential technology change should be advised. This study identifies and analyzes the differences of environmental impacts between ac and dc microgrids within office buildings to assist with smarter and more sustainable grid design in buildings. The differences in power electronics and distribution systems have been investigated on a micro-level in a comparative and scalable life cycle assessment and combined on a macro-level within a generic grid model. The analysis shows that the environmental impacts of power electronics can be reduced when utilizing a dc microgrid. The main driver for the differences in impacts has been identified as the energy supplied by the public grid. It can be inferred from the results that dc microgrids with integrated high-efficiency components have an ecological superiority compared to ac microgrids