Reducing Environmental Impacts through a Smart Design of Microgrids: Life Cycle Assessment for AC and DC

Microgrids with integrated renewable energies show promising potentials in terms of reliable, efficient, and clean smart grid concepts. Further improvements are expected when such a microgrid is operated on a direct current instead of an alternating one. Our study aims to systemically analyze the environmental impacts of microgrids operating on ac and on dc using power distribution within office buildings as an example. For this purpose, a comparative and scalable life cycle assessment is conducted based on a technical bottom up analysis of differences between ac and dc microgrids. Particularly, our approach combines the assessment of required power electronic components on a micro-level using a generic grid model on a macro-level. The results indicate that the environmental impacts of employed power electronics can be substantially reduced when utilizing a microgrid operating on dc instead of ac.