Executive Summary

Direct Current (DC) microgrids in buildings are evolving and expanding. There is a need, and an industry desire, to see more awareness, tools, education, and standardization in the DC marketplace. The alternating current (AC) market has been in place for over a century. While DC has been around for longer, AC dominates the industry. However, this may change since, over the past decade, new and more efficient DC devices have been introduced to building systems. Further, the lower cost and higher benefits of distributed energy resources (DER) such as photovoltaic (PV) power and battery storage are increasing in popularity. Interconnecting DER with DC technologies is creating microgrids that are evolving beyond the current set of standards documents and safety protocols.

CSA Group published a research report in March 2019 [1], which produced an important knowledge base, as well as a list of high-priority items for standards development. To expand upon the initial research, this report summarizes insights from a workshop involving over 40 Canadian industry stakeholders who were asked to visualize the DC microgrids of the future (2030); explore the DC microgrid value; uncover tools needed to capture that value; and identify solutions to barriers and opportunities. They were also asked to provide their views on the highest priorities for standardization and research needed for DC microgrids to be successful, efficient, and safe. The potential value of DC microgrids; the tools, solutions, and standardization needs; and the further research required as identified in the workshop are summarized herein.

• Value proposition – Stakeholder feedback identified several key items that form the value proposition for DC microgrids in buildings. The highest-rated values included energy savings; interoperability of systems; integration of renewable energy, including the reliability/business continuity it provides; and improved experiences.
• Tools – Stakeholders identified several value enablers for DC microgrids in buildings, including awareness and education; DC standards documents; government policies and regulations; and demonstration projects and incentive programs.
• Opportunities and barriers – Many of the value propositions described earlier are predicated on the ability for DC microgrids in buildings to operate seamlessly with other DC and AC systems. The opportunities identified included return on investment; sustainability, climate change, and renewables; and international economic development opportunities. The barriers to DC microgrids were identified as grid connection rules and regulations; and current AC infrastructure. Solutions for these opportunities and barriers were explored in the workshop and included demonstration projects, case studies, engagement with policymakers and utilities, and expansion of codes and standards.
• Standardization requirements - With a clearer understanding of the value and interoperability of DC microgrids, high-priority areas urgently needing standards documents were identified. The highest priority items included standard DC voltages; DC receptacles; DC connector plugs; DC voltage ranges; DC overcurrent protection; and standards for health and safety. In addition, there were several standards identified that should be developed in both the medium to long term.

Topics to further the development of DC microgrids - Other initiatives were raised that could further the development of DC microgrids in the buildings industry, including research activities, pilot programs, and incentives. For example, stakeholders concurred that the industry would benefit from a roadmap exercise that would summarize the current landscape for DC systems and propose a path to integration and transition from AC to DC systems. Further, the implementation of pilot projects in buildings with high-value attributes such as green buildings and electrified mobility could ease adoption of the technology while linking DC with a superior brand.