Research Taking a Shot at Improving Solar Energy

SunShot might sound like the next wave of NASA missions, or perhaps even the latest weapon of a James Bond villain, but it’s a US Department of Energy research initiative that holds the potential to reshape the way we think about, gather, and use solar energy.

The US Department of Energy logo for the SunShot Initiative.

The SunShot National Laboratory Multiyear Partnership recently awarded a $2.3 million, thirty-six-month project to UT’s College of Engineering and its collaborators.

“There is great potential in the United States to better make use of solar power possibilities,” said Yong Liu, research assistant professor of electrical engineering and computer science at UT. “Our study will look at problems inherent to current photovoltaic power generation, its effect on the U.S. power grid frequency stability, and how to mitigate its effect in order to avoid large blackouts.”

Photovoltaic power, or PV power, converts solar energy to electricity without burning fossil fuels and is considered the carbon-free solution for our energy problem.

While the best-known example is the standard solar panel that has been around for decades, breakthroughs in technology have provided reduced cost as well as increased efficiency, which in turn greatly increases the potential capacity of PV plants.

This potential surge of grid-connected solar arrays has raised concerns with utility operators about the potential impact solar energy could have on power grid stability, but knowledge is scarce on both the problems that lie ahead and the solutions for current problems.

“Our preliminary studies already demonstrated that the overall frequency response of US power grids will deteriorate significantly with rapidly increasing renewable power generation,” said Liu. “A case study in wind power in Ireland also backs this up, so clearly renewable energies pose some serious challenges that traditional power production does not.

“That is the main challenge we seek to answer.”

The team will set about answering that challenge in three phases:

  • Developing a wide range of PV penetration scenarios based on accurate interconnection models and realistic PV location projections
  • Achieving an understanding of the frequency impact on the grid
  • Developing and testing options for low system inertia and reduced frequency response problems

The team, led by joint UT-Oak Ridge National Laboratory Governor’s Chair and Deputy Director of CURENT (the Center for Ultra-Wide-Area Resilient Electric Energy Transmission Networks) Yilu Liu and including ORNL’s Aleksandar Dimitrovski and Stanton Hadley, the National Renewable Energy Laboratory’s Yingchen Zhang, and General Electric’s Maozhong Gong, will run tests on three North American interconnection models and GE’s Hardware-in-the-Loop facility, giving them an unprecedented amount of data.

Once complete, those steps and tests will help prepare the United States for solar power generation of up to 14 percent of the nation’s total electricity demand by 2030 and 27 percent by 2050.



David Goddard (865-974-0683,