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Unlocking Hidden Grid Capacity with Heimdall Power’s Neurons

Great River Energy is unlocking untapped capacity (and decreasing costs) by partnering with Heimdall Power, a c­­ompany that specializes in power grid optimization.

Following an internal planning study to identify transmission lines with potential congestion and the highest financial impact, Great River Energy selected a line in West Central Minnesota for a pilot project. The pilot project utilized Heimdall Power’s “neurons,” which are sphere-shaped sensors that can be easily installed by autonomous drones or line technicians on energized high-voltage power lines to dynamically rate the line using current weather conditions. 

Crews installed four of the sensors on the Morris to Johnson Junction line near Morris, Minnesota, last September to collect and measure real-time data on conductor current, conductor angle, conductor temperature and weather conditions such as ambient temperature and wind speed. This data is transported by cellular connection and processed by Heimdall Power’s software platform, using machine learning algorithms to understand the real-time capacity of power lines.

Congestion can change by the minute and is based on a variety of factors, including scheduled transmission line maintenance and generation dispatch variability typically associated with wind generation. In general, wind power production increases when wind velocities increase. Wind also has a significant cooling impact on transmission line conductor temperatures, leading to increased transmission line capacity of lines near these wind generation resources. This enables increased wind power production and transfer using dynamic line rating (DLR) technologies.

Historically, Great River Energy has used static summer and winter line ratings derived from conservative estimations for weather and known equipment properties to determine line capacities. The sensors allow Great River Energy to combine the conductor properties with real-time data for conductor temperature and ambient weather conditions to calculate a more accurate rating with the goal of increasing transmission line capacity.

The pilot project indicated the potential gains the cooperative could realize through DLR, showing an increase of more than 25% capacity nearly 70% of the time, and an overall average increase of 43% in capacity when compared to the current static rating.

Michael Craig, supervising manager, energy and distribution management system, is pleased with the results from the pilot project and said Great River Energy is now adding 52 sensors on several more transmission lines this summer. This is the largest project of its kind in the United States.

“This technology allows us to unlock new capacity from our existing infrastructure,” Craig said. “This method is more accurate compared to seasonal ratings as it can use actual line conductor temperature to determine the capacity of the line and ensure it is not becoming too hot. Drawing from this success, we aim to deploy additional sensors along key congested lines where the line conductor acts as the limiting factor, aiming to curtail overall congestion costs for Great River Energy and member-owners.”

By understanding the real-time capacity of power lines, Great River Energy can optimize its transmission assets and set safe, new operational limits to keep costs low and integrate more resources, including renewable energy, into the existing grid.

– Heather Reinhart, Communications Specialist, Great River Energy

About the Author

Heather Reinhart, Communications Specialist, Great River Energy

Heather Reinhart is the communications specialist supporting the transmission division at Great River Energy. She has a bachelor’s degree in journalism from the University of Wisconsin-Eau Claire. After years of working in newspapers and magazines, Reinhart has spent the past five years working with Minnesota electric cooperatives, including Wright-Hennepin Cooperative Electric Association. She is a previous member of the Minnesota Rural Electric Association’s Member Service and Communications Board of Directors.


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