Smart DC micro-grid for efficient utilization of distributed renewable energy

Abstract

A new, smart distributed DC micro-grid suitable for high-penetration and that efficiently utilizes energy available from distributed, renewable generators is described. It is shown that energy saving in excess of 10% is feasible using the proposed DC power distribution system when compared to the current approach where inverters are used. This conclusion is substantiated by first-order calculations of a 50 kW solar photovoltaics (PV) array delivering power to DC-compatible electrical loads typically present in a household and/or commercial building. Further energy saving may be achieved by replacing state-of-the-art silicon-based DC-DC power converters with more-efficient emerging Gallium Nitride (GaN) FET converters at a reduced cost. The proposed DC micro-grid architecture is hybrid in nature and is easily scalable to other power levels. It is ideally suited for residential and commercial applications as well as for powering sustainable communities.