Techno-economic Evaluation of Residential DC Power System for Multiple Distribution Voltages

Abstract

DC Power Systems or DC Nanogrids (NGs) in modern homes are candidates for improving efficiency beyond the utility meter. DC distribution in these houses must be evaluated in the context of costs, load rating and spatial distribution along with optimum conductor usage to minimize the overall upfront and operational costs. This paper entails a framework to select the best-suited voltage for a residential DC NG with DC loads. The developed model considers loads and length of wires as variables, hence it is modular and scalable to larger residential units or commercial buildings. The model is tested from an efficiency and cost perspective at a typical residential house with 2.5 kW DC load with three distribution voltages i.e., 24V, 48V and 380V. Results show that 48V is the best candidate for the residential settings based on efficiency and techno-economic analysis incorporating conversion as well as distribution losses.