After 10 years of planning and a $111.5 million grant from the U.S. Dept. of Energy, a smart grid network that’s expected to save the regional utility and area businesses tens of millions of dollars annually is close to being fully up and running in Chattanooga, Tenn.
Add to that a world-class, high-speed Internet pipeline available to everyone, and the city historically known for its famed Choo-Choo has the infrastructure in place to continue its stunning turnaround.
The $220-million smart grid initiative began a decade ago, when the not-for-profit Electric Power Board (EPB) of Chattanooga found it was restricted from implementing automation because it didn’t have the necessary communications technology. First, EPB entered the telephone business, followed by Internet services more than eight years ago.
“We found they were complementary,” said Harold DePriest, president and CEO of EPB, a municipal utility with a 600 square-mile territory. “There are huge similarities in high-power communications and electric networks.”
The utility now boasts one of the fastest Internet pipelines in the world, offering existing customers an ultra-high speed connection up to a whopping one gigabit per second—more than 200 times faster than the average U.S. download speed. As part of its network, EPB also offers TV and telephone services.
Smart grid
With more than 6,000 miles of electric line, plus nearly 170,000 meters and thousands of poles, transformers and other equipment that deliver power to customers in the greater Chattanooga area, the smart grid is a fiber optics communications infrastructure that enables utility components to share information, while also communicating with customers and personnel at EPB.
Previously manual tasks of meter reading and power outage reporting will soon be handled through near real-time communications between components on the electric grid itself, saving the utility $3 million, annually.
“Chattanooga is the epicenter of energy technology,” DePriest said. “One of our biggest jobs is to exploit this technology for the benefit of our community.” 1
With the smart grid in place, EPB will now know instantly when power outages occur, rather than relying on customers to report them. EPB can react automatically to some types of power outages, re-routing power and reducing outage restoration time to seconds for many customers rather than minutes or hours. This was demonstrated last summer, when EPB saved $1.4 million by cutting power outages 55 percent after a major windstorm blew through the area in July, thanks to 1,200 automated switches installed on the grid during 2011.
“As we have continued to build out this smart grid network, our reliability has improved because we are able to quickly isolate calls or problems,” says Dave Peirano, manager of communications and controls engineering for the EPB.
With the rapid advance of technology, cutting-edge utilities such as EPB are now measuring reliability in terms of minutes, Peirano says. With sophisticated meters attached to homes and businesses, EPB can monitor outages remotely, and respond to outages faster—sometimes before a customer is even aware that they lost power.
“In the past, we would have to dispatch a troubleshooter to isolate the problem by using a trial-and-error approach that involved opening and closing switches,” Peirano says. “Now, that is all happening within seconds, and we are restoring power much faster.”
By interpreting software data from the smart grid, EPB will be able to help customers better manage their energy usage. The utility can now alert customers when there are unusual spikes in their power consumption before those spikes result in a higher-than-expected bill. With near real-time data available through smart meters, customers will be able to make choices about when to use electricity, thus better managing utilization and budgets. Industrial customers are paying particular attention to the potential benefits of the smart grid, as time-of-use pricing will be one of the services available through the new network, DePriest says.1
Cat generators at the ready
The smart grid is connected by a ring of nine supernodes, which store fiberoptic networks for data, voice and video, while also connecting EPB’s smart grid network. The supernodes are housed in small huts strategically located throughout Chattanooga, and are backed up by Cat® 100 kW gensets located adjacent to each communications facility.
Because supernodes have climate control systems inside, and the battery power backup is not powerful enough to run an HVAC unit, “we knew we had to have a backup generator in case we lose utility power,” Peirano said. “As soon as utility power is lost, the transfer switch activates the backup system and the generator fires up within 7 to 8 seconds. Once we are transferred to the generator inside the hut, all the equipment is running like it never knew.”
The amount of DC electric load running to one of the nodes is 125 amps at 48 to 54 volts. Add in the HVAC units, and based on the expansion that EPB anticipates, engineers determined that 100 kW generators were sufficient for its needs. Currently, when the generators come on they run at about 70 kW.
The supernodes are critical because they are all connected, meaning that if one were to go down it would affect the entire ring–which serves as the communication backbone for the utility’s smart grid, and also carries voice and video.
“Within this node, we create an RF video picture for our customers,” Peirano says. “Also from here, we transmit out to a couple of remote nodes, and they distribute it to even more customers. So if one node was down, we would have a lot of customers without standard analog TV. Those communications are running through here, and then all of the residential and business phones are going to run back here. So, it’s very critical that we keep power on throughout the network.”
Over a three-year period, a generator at a location on the east side of the city has run twice to support the loss of utility power. With other nodes, such as one at the top of Lookout Mountain, the Cat generator set is a huge asset in instances where a tree falls and severs a utility line, Peirano says.
“Another benefit that we really wanted to derive from a genset was the ability to have some telemetry that delivers alarm set points to our supernode,” Peirano adds. “These alarms come back to our central dispatch, so we know if these gensets are low on fuel. We know when they’re running, or if we are running on generator power or utility power. We know if we have low coolant. We have all kinds of monitoring and alarms that tie in, so that’s a great feature.”
Partnering with Stowers
Technicians from EPB’s Cat Dealer, Stowers Power Systems, pre-programmed the generator outputs, and EPB crews took care of the rest, running copper wire into the supernode.
Once a week, each generator starts and power switches over to the generator for 30 minutes, Peirano says. EPB technicians also perform a visual inspection eight times a year by opening up the access panel on each genset, checking the fuel gauge, and looking for any visible leaks or loose cables.
All fluids and filters are changed by a Stowers technician on an annual basis. Every other year, load bank testing is performed and the gensets run full out for two to four hours.
“When you just start your car and let it idle in the driveway, that’s not the same thing as getting it out on the Interstate, which is the equivalent of what we do when we load test,” Peirano says. “It’s great maintenance, and Stowers does it all for us. They were less expensive than doing it ourselves.”
Peirano finds his Cat Dealer easy to work with. His calls are answered within the first two rings, and on those rare occasions when an issue crops up, a technician is dispatched within two hours.
“He’s on site, and he’s letting me know what is going on and how they are going to fix it,” Peirano says. “Stowers has great customer service and parts availability. And if they don’t have the part, it’s a one-day turnaround. It has just been great support. They are a true partner.”
1 Harold DePriest’s comments were originally published in a January 2011 article by Greentech Media.
The Smart Grid, a fiber optics communications infrastructure, enables all components that are part of the Chattanooga EPB utility system to “talk” to each other, as well as communicate with customers and personnel at EPB.
The system has nine supernodes, and eight remote nodes, and the nodes act as distribution hubs for the fiber optics communications. There are no electronics past the nodes until the end user is reached. The fiber optic nodes are connected on a ring to maximize redundancy for the EPB customers.
The equipment inside each node provides data, voice, and video to EPB customers. It also provides Smart Grid network data to a system control and dispatching center.
Back on Track
In 1969, Chattanooga was identified as the most polluted city in America by the U.S. Environmental Protection Agency (EPA). That same year, CBS news anchor Walter Cronkite called Chattanooga America’s dirtiest city.
The same mountains that provided Chattanooga’s scenic backdrop also served to trap industrial pollutants, causing them to settle over the community. Decreasing population and increasing crime made downtown a place to avoid. Terminal Station, the destination of the Chattanooga Choo Choo, closed in 1970.
By the late 1960’s, the iron and steel business was destroyed by foreign competition. The last coal mine closed. And reductions in the textile and apparel workforce totaled 25%. To some it seemed as though this was the final nail in Chattanooga’s coffin. To others, it was a wake-up call.
“It was a city that was almost let go,” recalls one local observer.
But, over the last four decades, the city made famous for Glen Miller’s big band swing tune “Chattanooga Choo-Choo,” has been winning acclaim for its unique way of working together to produce national best practices for cleaning up air pollution, revitalizating its downtown, attracting new business, creating a widely available high-speed Internet, and developing a self-diagnosing energy smart grid.
In 2008, the Scenic City was rated the third best place to live in the U.S. by RelocateAmerica.com.
The turnaround started in 1973, when a group of local executives redeveloped the train station as a tourist site and hotel. By the 1980s, the city began to revitalize its riverfront, and by the mid-1990s, the downtown boasted new museums, a theater and an aquarium.
Chattanooga has not just cleaned up its air—it has passed EPA emissions tests since 1988—but has implemented a number of sustainable practices that place it leaps and bounds ahead of many American cities in trying to balance ecology with economic growth.
According to a published account earlier this year from The Wall Street Journal, tax incentives and land grants totalling about $630 million were used to help attract $2 billion of investment from dozens of companies such as Volkswagen AG, Amazon Fulfillment and Alstom SA—which helped to create more than 7,500 jobs and turn the once struggling town into one of the nation’s strongest local economies.
“Residents who have lived here for a long time once again have hope,” said Mayor Ron Littlefield, whose city has a population of about 170,000. “We aren’t losing our young people. We are attracting other places’ young people.”
— Reprinted from RunReady™ magazine with permission from High Velocity Communications. ©2012 High Velocity Communications Inc.