PNNL

Abstract

Driven by the proliferation of DC energy sources and DC end use devices (e.g., photovoltaics, battery storage, solid state lighting, consumer electronics), DC power distribution in buildings has recently emerged as a path to improved efficiency, resilience, and cost savings in a transitioning building sector. In spite of these important benefits, there are several technological and market barriers that impede the development of DC distribution, thus maintaining the market for DC in buildings at the demonstration phase. This identifies specific end-use cases for which DC distribution in buildings is viable today by evaluating their technology and market readiness, as well as efficiency, cost, and resiliency benefits, while addressing implementation barriers. The paper starts with a technology review, followed by a comprehensive market assessment, in which we analyze DC distribution field deployments and their end-use characteristics. We also conduct an elicitation of DC power and building professionals through on-site visits and phone interviews and summarize lessons learned and recommendations. The paper also includes a novel efficiency analysis, in which we quantify energy savings from DC distribution for different end-use categories. Based on our findings, we present specific adoption pathways for DC in buildings that can be implemented today, and for each pathway we identify challenges, and offer recommendations for the research and building community.