Electricity powers our work and our lives, keeps us warm in the winter and cool in the summer, and drives the economy. The distribution of electric power around the world—electrification, as it’s called—is so important, it was named the greatest engineering achievement of the 20th century by the National Academy of Engineering.
Nevertheless, our electric grid is getting long in the tooth. When it was conceived and implemented, the grid’s architects did not face many realities of the new millennium that challenge both the security of our modern electrical system and the business model of those companies that run it.
Consider renewable energy sources such as wind and solar power; they don’t produce electricity so much when they’re needed as when it’s windy or sunny. Utilities, on the other hand, need to provide power whenever someone flips a switch, no matter the weather or the time of day. Or look to the homes and businesses that save money by installing their own solar generators. Power plants must be paid for, even when people spend most of their time off the grid.
“Utilities are extremely concerned about those distributed, renewable generation technologies and how to respond,” ORNL’s Tom King said.
In addition, consider the potential consequences of a disaster. Imagine a catastrophic storm or well-planned attack, whether physical or virtual. Our economic well-being—as well as our physical health—depends on our ability to avoid and, especially, to weather such events.
Recognizing the importance of our electrical grid, the Department of Energy has responded with the Grid Modernization Initiative, a program designed to bring this most important of technologies into the 21th century. The related Grid Modernization Laboratory Consortium is a partnership of DOE labs, including ORNL.
One focus of the initiative being led by ORNL is grid sensing and measurement. “To address a lot of these threats, we need to know what’s going on and have more visibility throughout the entire system,” King said.
FNET/GridEye, for instance, employs a network of frequency disturbance recorders. Each monitor, about the size of a small piece of stereo equipment, is a GPS-synchronized sensor that plugs into an electrical outlet and an Ethernet connection.
The network (FNET stands for Frequency Monitoring Network) is the brainchild of Yilu Liu, an electrical engineer and governor’s chair with the University of Tennessee–Knoxville and ORNL’s Electrical and Electronics Systems Research Division. It keeps track of a system’s electrical frequency and voltage angle, monitoring the health of the electrical grid in much the same way an electrocardiogram monitors the health of a person’s heart.
“When a generator comes off line, it creates this ripple effect,” King explained, noting that such disruptions could set off oscillations in the electric grid. “We have a 60 hertz system. Well, if you throw a rock into a lake, you get major waves and ripples, and you want to avoid them as much as possible.”
ORNL researchers are also developing low-cost, printed sensors that monitor a building’s environment. The sensors themselves are passive, meaning they require no power of their own; instead, they draw power from the radio waves emitted by the device used to read them.
These Radio Frequency Surface Acoustic Wave devices—better known as RF SAW—use tiny sensors to measure conditions such as temperature and humidity.
“These can not only monitor and control buildings better,” said ORNL physicist Tim McIntyre, “but allow them to be integrated with the grid. The way to make all the pieces of the grid play together better is to have large-scale sensor networks that give you detailed, real-time information about each of those pieces.”
Because they will be printed—specifically with an aerosol jet printer—the sensors will be inexpensive, from less than a dollar to a few cents apiece. The project is in its early stages, McIntyre noted, adding that although RF SAW devices have been produced before, they have not been manufactured by direct printing.
See also:
- ORNL researchers go for a big impact
- Grad students create biotech company, continue research project
- Infographic: ORNL regional partnerships
