By Paul Wesslund
Solar panels, electric cars, computer hackers, vandals and thieves might not seem to have much in common, but they’re all making big changes in your electric service. Those changes have electric utilities talking about “the substation of the future.”
If everything goes according to plan, you may never even know about those changes, says Tom Lovas, a technical liaison and consultant with the National Rural Electric Cooperative Association.
“The traditional model of generation, transmission and distribution is kind of being turned on its head,” Lovas says. “In the past, power flowed to a substation and then flowed out to the consumer. … [T]he substation has now become a point of information and interconnection, and it’s coordinated in a different way.”
Before making sense of what Lovas means by a substation becoming a point of information, it helps to understand what a substation does.
HOW SUBSTATIONS WORK
That mass of wires and equipment you see behind chain-link fences as you drive along freeways or side roads basically turns high-voltage electricity into lower voltage electricity that can be used in your home. Electricity generated at a power plant gets “stepped up” to a high voltage at a substation because that’s a more efficient way for power to make the long-distance journey through transmission lines. When the current gets close to where it will be used, another substation steps the voltage down, for distribution to you and your neighbors.
But that straight-line path for electricity is changing, says an international industry group planning for how the substation of the future will fit in with the power lines and power plants that make up the electric grid.
“Rather than continually getting bigger, the grid is now increasing in intelligence,” according to a 2016 strategic plan of the Centre for Energy Advancement through Technological Innovation (CEATI International). “Customers are increasingly looking for ways to manage their own energy, customizing how they use it and serving as suppliers of energy.”
One example of customers serving as suppliers of energy is the fast-growing number of homeowners installing rooftop solar panels. Now, electricity doesn’t just flow from a power plant through a substation to a house. Instead, electricity also flows in the opposite direction, from the house, then back onto the grid as homeowners sell excess solar power back to their utility.
When power flows in both directions, running a utility gets a lot more complicated. First, there’s safety. Lineworkers need to be sure they know which wires are energized and which are not. Electricity traveling in a different direction could put new stresses on old equipment, and utilities need new ways to monitor electric current so they can keep track of new patterns of electricity use and generation.
Lovas cites an increase in electric cars as another new addition that could change electricity use as people charge their vehicles at a variety of times and places.
PREDICTING POWER OUTAGES
Electric utilities are analyzing information about where the electricity is coming from and where it’s going. This information can be used to improve operations in the utility network and can make the substation of the future an important part of “the smart grid”
Information collected at a substation could keep track of how transformers are performing so they could be replaced before they fail or even recognize power use patterns that could predict an outage.
“We collect zillions of data points of information. What we’re trying to do is make sense of what that information is telling us,” Lovas says. Figuring out how to analyze and use all that data, he says, could improve safety, reduce outages, reduce outage duration and reduce maintenance costs.
These days, we know that information can also be stolen or misused by cyber criminals, so the substation of the future needs stronger security. And not just cyber security. Lovas says that substation planning needs protection against more old-fashioned attackers like vandals and copper wire thieves. CEATI International wrote in its strategic plan on the substation of the future, “In the new environment, station facilities have to be protected from physical tampering, sabotage or theft and also from malicious threats to data and/or control systems connected to cyber networks.”
Lovas also expects the substation of the future will respond to concerns about what substations look like, with utilities looking for more remote locations or planting trees around them. Underground substations could offer better security, as well as avoid complaints about the appearance of the collection of wires and equipment.
When will we see the substation of the future? Maybe never, if it’s hidden behind a grove of trees. Or, since improvements and advancements are already being installed, maybe it’s already here. “I don’t think there’s any defined date when the substation of the future takes over,” Lovas says. “It’s just a natural progression of things.”
Paul Wesslund writes on cooperative issues for the National Rural Electric Cooperative Association.