Engineers at the U.S. Department of Energy’s Argonne National Laboratory have designed a novel building-solar controller that optimizes solar energy with smart technology to keep microgrids operating for up to five days. The Argonne project was funded by the DOE Solar Energy Technologies Office to advance research in solar energy technologies.
Utility companies can restore most power outages within 7-10 days of a natural disaster. But a five-day power supply is a reasonable threshold to allow isolated microgrids to provide power during most outages, said principal investigator, Bo Chen, an Argonne computational scientist.
Microgrids come in a variety of sizes and can generate enough power for a few homes or an entire community. The grids offer the opportunity to use more zero-emission electricity sources which reduces greenhouse gas emissions.
As technology gets smarter, the buildings themselves can essentially be transformed into microgrids, or grid-interactive efficient buildings. These buildings use smart controls, sensors, and analytics to communicate with the electrical grid.
Argonne’s novel building-solar controller is an algorithm and framework that coordinates multiple grid-interactive buildings, solar energy, and other energy resources in one integrated network.
While solar power is environmentally friendly, the renewable energy source is dependent on weather and is not available continuously. To ensure a consistent, reliable energy supply for five days, the Argonne team relied on an energy storage system that captures energy for later use.
“Energy storage works as a buffer that absorbs power when there is a surplus and releases power when there is a deficit,” said Chen. “In this way, we can continuously balance electricity supply and demand to ensure a reliable power supply.”
Argonne worked with public and private partners including utilities and educational and research centers on the three-year project completed in late 2021.
The team successfully tested the framework in a real-world microgrid at the Illinois Institute of Technology (IIT) in Chicago. The team applied the framework to the real-world microgrid on the IIT campus. Chen said the team demonstrated in real time how solar, wind, energy storage and variable power loads keep the lights on in various power outage scenarios.
A single building microgrid is limited by capacity, response speed and other factors. The team showed that multiple building microgrids can complement each other to expand grid service capability and restore power more quickly.
The framework is primarily targeted for use by utility companies, which can directly embed the framework into their control centers. Private vendors can also incorporate the flexible network into existing products. Still in the early stages, the framework will eventually be available in a free, open-source format.