Clemson University plays key role in updating nation’s electrical grid
CLEMSON — Clemson University is working with industry to revolutionize how electricity is generated and delivered to homes and businesses as new technology opens the door to the first major overhaul of the electrical grid since it was built a century ago.
Some of the country’s top researchers are developing “smart grid” technologies that will integrate more green energy and help meet customers’ demands to generate and share some of their own power.
Researchers are also looking for new ways to keep the grid secure, help drive down the cost of renewable energy and make the system more reliable and efficient.
At stake for the nation are the power plants and grid of transmission-and-distribution lines that make modern life possible, whether it’s keeping on a home’s lights or powering sophisticated factory machinery.
Much of Clemson’s work is taking place in world-class labs that were supported by millions of dollars in public and private contributions and give students unmatched hands-on experience.
Randy Collins, who has been working with the electrical grid and its technology for more than 25 years, said that he has seen an explosion of interest in energy and related technology just as the industry is facing a wave of personnel retirements.
“The career opportunities for our students are phenomenal and should continue for many years,” said Collins, a professor of electrical and computer engineering who also is associate dean of undergraduate and international studies in the College of Engineering and Science.
‘How it all works is changing’
The electrical grid is one of the nation’s greatest engineering achievements of the past century, but it has undergone few big changes since it was built, even as computers and other technology have become more sophisticated.
Electricity has historically been generated in large, centralized plants to take advantage of economies of scale, then sent to customers over a network of wires.
But experts in academia and industry see a future that incorporates new energy contributors distributed across the electrical grid. Those contributors could include customers who generate and store some of their own power and operators who run wind and solar farms as businesses, experts said.
The new additions mean that a system originally designed to send power in one direction — from utility to customer — will now have to go both ways, said Clemson’s J. Curtiss Fox, director of operations for the Duke Energy-sponsored eGRID and a former student of Collins.
“The model and how it all works is changing,” he said. “You take a system that you’ve perfected to work in one way over 90 or 100 years and start saying, ‘OK, we want to dramatically change how that works.’
“That’s where the challenges come in.”
Wind and solar’s larger role
Utilities need to balance the demand for electricity with the supply they are sending into the grid. A shortfall in supply can trigger cascading blackouts, as interconnected parts of the grid are successively overloaded.
The system that has been in place for decades has allowed utilities to make automatic adjustments based on customer demand. But adding new grid contributors, including some not controlled by utilities, introduces unpredictability and complexity that makes it more difficult to keep the electrical flow balanced.
“The biggest challenge is how you integrate all these emerging technologies with central plant generation but do it in the most efficient manner,” said Zak Kuznar, senior project manager for emerging technology at Duke Energy.
As wind and solar energy play a bigger role, more of the power available for use in the grid will increasingly become subject to wind speeds and cloud cover.
While shortfalls in wind and solar power can be balanced with conventional means, weather forecasts aren’t accurate enough to predict with precision how much conventional power generation will be needed, said Kumar Venayagamoorthy, Clemson’s Duke Energy Distinguished Professor of Electrical and Computer Engineering.
“We know how to integrate renewables: sensors can be put on the grid,” Venayagamoorthy said. “But the question is how can we process the information just in time to keep the grid together.”
Venayagamoorthy is working on a monitoring system at the Real-Time Power and Intelligent Systems Laboratory on Clemson’s main campus.
Securing the grid
Keith Corzine, who also is based on the main campus, is working to make the nation’s flow of electricity more secure. The importance was underscored in April 2013 when gunmen attacked a Silicon Valley substation, he said.
“This kind of attack at multiple locations around the country could take out the grid,” said Corzine, who is the Warren H. Owen-Duke Energy Distinguished Professor of Electrical and Computer Engineering. “We are all completely dependent on electric power. Without power, you can’t put gas in your car. You can’t refrigerate or cook the food in your home.”
He is working to develop new technology to advance “microgrids” that cover a limited area, such as a neighborhood or office park, and generate power locally without dependence on the nationwide grid.
While the nation’s grid runs on AC current, many microgrids run on DC to help bring down the cost.
One of the troubles with DC systems is that they have limited circuit-breaker options to take them offline when something goes wrong, Corzine said. The electricity keeps flowing, leaving the system vulnerable to fire, he said.
Corzine said he has designed and built advanced DC circuit breakers and is now doing laboratory tests.
Clemson has some of the world’s top facilities for energy-systems development and testing. Their funding underscores the importance of public-private partnerships to work for the common good as a new energy economy is developed.
With a $5 million gift, Duke Energy named the eGRID, which stands for Electric Grid Research, Innovation and Development. Duke provided funds for laboratory infrastructure, educational program development and a Smart Grid Technology Endowed Chair for a future Clemson faculty member.
The eGRID is a 15-megawatt “hardware-in-the-loop” simulator that can replicate any grid in the world to investigate how the grid and advanced devices, such as wind turbines and solar arrays, interact with each other, especially when the grid becomes unstable.
While valuable for testing, the eGRID will also provide crucial experience on cutting-edge technology to the students who will become next generation of grid- and power-system engineers, said Sam Holeman, Duke Energy director of system operations engineering and training.
“They’ll bring this skill set to the companies they work for,” he said.
South Carolina Electric & Gas (SCE&G), the Lowcountry’s primary provider of electricity, supported the center with a $3.5 million gift.
“Right in our own backyard, we’re going to be able to figure out how to change the whole energy economy in South Carolina,” said Danny Kassis, vice president of customer relations/renewables for SCE&G.
Reducing wind energy costs
The Restoration Institute also houses the world’s most-advanced testing facility for wind turbine drivetrains. The $98-million facility included $53 million in state and private contributions and a $45 million award from the U.S Department of Energy’s Office of Energy Efficiency and Renewable Energy.
A drivetrain takes energy generated by a turbine’s blades and increases the rotational speed to drive the electrical generator, similar to the transmission in a car.
Many of the failures in the field are due to mechanical stresses in the system, Fox said.
“Those are very expensive to fix 100 meters up in the air,” he said. “If you have any plans of going offshore with it, you no longer have a stable crane base. Things get even more difficult and more expensive out there. The reliability of the mechanical components needs to be brought up.”
The upshot is that Clemson’s work to make drivetrains more reliable cuts down on maintenance costs, which reduces the cost of wind energy.
Elham Makram, the South Carolina Electric and Gas Distinguished Professor of Electrical and Computer Engineering, said the hand-on experience offered at the institute can’t be taught in the classroom and is one that not many universities offer. She is sending two graduate students to Charleston this year and expects to send more in years to come.
“It really prepares them to have real contribution in industry,” said Makram, who also is director of the Clemson University Electric Power Research Association (CUEPRA). “It’s a different kind of experience.”