ERC Startup Company GridBridge Conducts Pilot Demonstration of an Energy Router

Achievement date: 

The NSF-funded Future Renewable Electric Energy Delivery and Management (FREEDM) Systems Engineering Research Center (ERC), headquartered at North Carolina State University, has nurtured spinoff companies to pursue FREEDM-developed technology. One of those companies, GridBridge, concluded a field demonstration of its Grid Energy Router (GER) at Brunswick Electric Membership Corporation (EMC) in North Carolina. The demonstration results were positive and were published in February 2016 by the Business and Technology Strategies group of the National Rural Electric Cooperative Association (NRECA).


The GER, nominally rated at 50 kVa, was installed downstream of an existing transformer that served an EMC maintenance facility (see figure). Communications to the GER over a Category 5 cable ensured highly reliable connectivity and control. GER input and output were verified using a separately installed Revolution Power Quality Monitor. As part of the positive assessment, NRECA concluded that this GridBridge product has a 2- to 3-year payback for this installation. The project will continue, including plans for future demonstration of other GER capabilities, such as DC bus connections and integration of distributed generation and peer-to-peer communications to enable microgrids.


The project goals were to provide an independent evaluation of some of the GER capabilities, namely dynamic voltage regulation and independent setting of power factor without capacitor banks or line regulators. As a pilot demonstration, the NRECA also wanted to understand device operation in typical environmental conditions, such as low- and high-ambient temperatures and low- and high-power flow.

GridBridge licensed core solid state transformer (SST) technology from FREEDM in 2012 and has developed a low-voltage version of the SST. Dr. Alex Huang serves as an adviser. The company occasionally hires FREEDM students for temporary work and has hired some graduates for full-time employment.