People in the United States experience more minutes of power outages than those living in any other developed nation – six time that of citizens of Italy, Germany, Japan and South Korea. Each day, power-grid outages of two or more hours affect 500,000 people in the United States.
Consider this comparison of the average annual number of power outage minutes of people living in these three areas: United States, upper Northeast, 214; United States, upper Midwest, 92; Japan, 4.
Meanwhile, weather-related power outages –which, like all outages, impose inconvenience and economic loss—are becoming more frequent worldwide.
While the country’s electrical grid infrastructure, which has evolved over the past 130 years without an over-arching plan, is problematic, any proposed changes to it must be “energy secure,” says Rob Cuzner, associate professor, electrical engineering. “An energy-secure grid delivers power when needed, transfers energy efficiently, is space efficient, and is resilient to blackouts and cyber security threats,” he says.
Emerging smart grid technologies, which include microgrids, provide the key to achieving all of the above.
Cuzner’s research focuses on improving the resiliency and efficiency of microgrids. His current and past research on integrated power and energy systems has been supported by the Office of Naval Research, U.S. Navy, U.S. Air Force, the National Science Foundation and industry partners including Eaton Corporation and Leonardo DRS.
Micro-grids are rolling out
Micro-grids, which are essentially micro-utilities for a limited area, are gaining traction. They can operate independently of big utilities by using locally generated power—including power from green energy sources—and storing energy. (Current U.S. infrastructure does not store energy.)
They are being relied upon in some contained communities, including U.S. military bases, U.S. naval vessels, at least one U.S. prison. DC micro-grids are being deployed on a grand scale in developing countries and the many rural and remote areas of India where the government grid is unreliable. Puerto Rico is considering turning the entire island into a micro-grid patchwork. Someday, micro-grids will power office buildings, industrial parks, neighborhoods and even cities.
Next up: a secure micro-grid
People get excited about micro-grids, Cuzner says, and there is a lot to be excited about. But before micro-grids can enjoy widespread use, researchers must improve their security. “Their behavior tends to be unpredictable in certain situations, such as when energy storage is turned off or added,” Cuzner says. “We are investigating new technologies to improve their dependability.”
Cuzner recently received a three-year grant of $245,156 from NAVSUP Fleet Logistics Center San Diego for his research project on energy secure hybrid AC/DC micro-grids. “We are working on improving the resiliency part of energy security,” he says. “The goal is a grid that can respond predictably to events, threats and failures.”
Micro-grids could help stabilize Milwaukee neighborhoods
Cuzner hopes to bring a micro-grid to a Milwaukee community, re configuring the power systems of individual houses and linking them through a neighborhood micro-grid that relies on DC current. The benefit? Significantly reduced utility bills, which could play a part in stabilizing neighborhoods where residents spend 16 percent of their income on utilities. “Ideally a micro-grid would lower a $200 monthly electric bill to $20,” Cuzner said.
To help him install and test a neighborhood micro-grid in Milwaukee, he is collaborating with a growing network that includes local community developers, private citizens, Aalborg University in Denmark and Purdue University.