Scientists at Oak Ridge National Laboratory Bridge the Gap in Power Electronics for the Grid of the Future
Department of Energy’s Oak Ridge National Laboratory leads the Medium Voltage Resource Integration Technology program to develop reliable and cost-effective power electronics for the medium-voltage range, filling a crucial gap in the modern electric grid.
Scientists at the Department of Energy’s Oak Ridge National Laboratory (ORNL) are working on a groundbreaking solution to enable the grid of the future. They are focused on bridging the gap between high and low voltages in power electronics technology that underpins the modern U.S. electric grid. This gap, known as the “medium-voltage” range, is critical for larger-scale renewable energy projects, larger equipment such as wind turbines, and larger electric vehicles like trains and vertical-takeoff aircraft. By developing devices that operate efficiently in this range, ORNL aims to help the U.S. achieve clean energy goals and expand capacity in the power grid without the need for extensive transmission line infrastructure.
The Need for Medium-Voltage Power Electronics
Today’s power electronics technology operates at the extremes, with low voltage used for tasks like charging personal vehicles or storing energy from solar panels, and high voltage used for utility-scale projects such as wind and solar farms. However, there is a critical gap between 1,500 and 50,000 volts, the medium-voltage range, which is essential for larger renewable energy projects and equipment. This gap needs to be filled to support the growth of clean energy and alleviate strain on the power grid.
The Medium Voltage Resource Integration Technology Program
To address this need, ORNL is leading the Department of Energy’s new Medium Voltage Resource Integration Technology program (MERIT). This program brings together four national labs and five universities to develop reliable and cost-effective devices that operate efficiently in the medium-voltage range. By filling this technology gap, MERIT aims to expand electric grid capacity, improve grid reliability, and enable the integration of renewable energy sources.
Benefits of Medium-Voltage Power Electronics
Filling the medium-voltage technology gap offers several benefits for the electric grid and clean energy integration. One significant advantage is the ability to efficiently convert power between alternating current (AC) and direct current (DC), which is crucial for renewable energy generation and electric vehicles. Medium-voltage power electronics could enable the transfer of excess electricity from regions with surplus supply to areas facing high demand, preventing blackouts and reducing reliance on backup power plants. Additionally, converting portions of the distribution grid from AC to DC using medium-voltage power electronics could increase delivery capacity and make clean energy transmission more efficient over long distances.
Medium-Voltage Research Leadership and Capabilities
ORNL researchers have been developing various medium-voltage building blocks, including converter modules, specialized magnetics, and protection mechanisms. These building blocks increase reliability and can be stacked to reach higher voltages. ORNL’s Grid Research Integration and Development Center (GRID-C) provides the necessary infrastructure to simulate different architectures, build and test converters up to 13,000 volts, and develop and test power electronics components.
Collaboration and Future Applications
ORNL will collaborate with utilities to identify medium-voltage needs and work with partners to develop full systems that can be installed and tested in the field. The Power electronics Accelerator Consortium for Electrification (PACE), an initiative created in 2022 to foster collaboration among research institutions, power companies, and manufacturers, will support these efforts. The ultimate goal is to demonstrate the operational and financial implications of medium-voltage power electronics in real-world applications, such as recharging electric trucks and producing green hydrogen.
Conclusion:
Bridging the gap in power electronics for the medium-voltage range is a crucial step towards achieving clean energy goals and expanding the capacity of the U.S. electric grid. ORNL’s leadership in the Medium Voltage Resource Integration Technology program, along with its research capabilities and partnerships, positions it at the forefront of developing reliable and cost-effective medium-voltage power electronics. By enabling efficient power conversion, increasing grid reliability, and facilitating the integration of renewable energy sources, this technology will play a vital role in the grid of the future.