The aim of this study was to examine, how the introduction of nanomaterials could affect the environmental life cycle impacts of grid installed high-voltage power capacitors. Another aim was to identify the parts of the product system, which cause the most environmental impacts, and which should be targeted for further ecodesign. The study was constructed as a comparison of two power capacitor banks: currently manufactured unit and an experimenta unit with nanomaterials used as an insulating medium in the dielectrics. The results were used to support product design decisions at a power capacitor manufacturing company.