Illinois utility’s microgrid first to ‘island’ nearby residential customers

Tucked away behind a research park at the University of Illinois Urbana-Champaign is a glimpse into what many industry analysts say is the future of the power industry. There on campus, a microgrid of solar panels, wind power, natural-gas generators and energy storage work in concert to balance electricity supply and demand.

Ameren Illinois, which serves power to 1.2 million customers across the state, completed the $5 million facility in December and formally unveiled it in May. The utility calls the nearly 1.5-megawatt microgrid one of North America’s most advanced distributed-energy-resource facilities.

It also serves as a physical and practical manifestation of a more connected, less centralized power system that has been discussed among Illinois policymakers and advocates for at least the past decade.

“Our focus on building a next generation energy delivery system has enabled Illinois to emerge as a national leader in smart grid innovation,” Richard J. Mark, chairman and president of Ameren Illinois, said in a statement. “As the technologies we are testing at this microgrid facility become more accessible in the future, our customers will be able to count on Ameren Illinois to help them safely install and cost-effectively operate distributed generation resources.”

In the near-term, Ameren Illinois hopes the microgrid can improve reliability for the more than 190 nearby homes it can power. In the event of a disruption to the broader power grid, the Ameren microgrid can “island” itself away from the rest of the system and continue to supply power to its local customers.

Farther down the line, the microgrid is poised to function as a cornerstone in a cleaner, smarter, more efficient power grid. This summer, Ameren Illinois plans to begin installing 83,000 smart meters in Champaign County, part of its plan to supply its entire service territory with Advanced Metering Infrastructure by the end of 2019.

The hope is that this kind of networked, distributed generation — when paired with more dynamic metering technology — can enable consumers to better manage what kind of energy they use and how they use it.

“They really will have control of their energy use … whether it be [reacting to] a price signal or [acting upon] a desire for green energy, those kinds of things that really give the customer control” says Ron Pate, senior vice president of operations and technical services at Ameren Illinois.

Customers ‘seamlessly supported’

The most visible components of the Ameren microgrid are the 100-kilowatt wind turbine, the 125-kilowatt solar array, the 250-kilowatt battery and the two 500-kilowatt natural gas generators. But the real power of the microgrid lies in the largely automated control system that ties all the pieces together, determining which sources generate power and to where based on real-time supply, demand, weather conditions and various economic indicators.

This setup allows Ameren Illinois to seamlessly transition customers from microgrid supply to the larger grid and back without any interruption.

“When a microgrid islands from the larger grid it loses all of the essential ancillary services that provide customers the quality power they need,” said David Chiesa, senior director of business development at S&C Electric, the Chicago-based company that provided the microgrid’s battery and intelligent automation. “Ensuring that customers are seamlessly supported by the distributed generation of a cyber-secure microgrid requires expert engineering, energy storage, and intelligent equipment that can think and act quickly.”

Another unique feature of Ameren Illinois’ system is that it functions at utility-scale voltage, between 4 kilovolts and 34.5 kilovolts. It also makes Ameren Illinois the first investor-owned utility to use a microgrid to island real, paying customers on an active feeder, according to S&C Electric.

However, Ameren’s is not the first or the only microgrid in Illinois. The Illinois Institute of Technology, a university on Chicago’s South Side, runs on an $18.5 million, 9-MW microgrid – which the school says had a payback period of five years. ComEd, Illinois’ largest utility, plans to build an adjacent microgrid that would be the country’s first pair of networked microgrids.

Across the U.S., installed microgrid capacity is expected to more than double to reach 4.3 gigawatts by 2020, according to an analysis by GTM Research.

Because of its proximity to UIUC’s highly ranked engineering school, the Ameren microgrid can also serve as an educational tool.

Tamer Rousan, a supervising engineer at Ameren Illinois and a UIUC graduate, says when he was in school the prevailing wisdom was not to go into power engineering because it was boring and hadn’t changed in decades. But now, he says, the subject draws a lot of attention from the nearby engineering students.

“Everybody is interested in solar and wind,” he says. “Everybody is interested in the smart grid … These guys come in with eyes wide open, really excited with what we’re doing here.”

From policy to practice

The story of the Ameren microgrid is also as much about legislative assertiveness as it is about engineering innovation.

Ameren’s Pate credits the 2011 Energy Infrastructure Modernization Act (EIMA) as sparking a conversation that led to the microgrid and other projects like it. The bill called on Illinois utilities to invest a combined $2.6 billion in infrastructure upgrades and smart-grid work, and is widely seen as spurring the proliferation of smart meters and efficiency programs in the years since.

The EIMA got a boost in December with the passage of the Future Energy Jobs Act. Although the final version of the legislation dropped funding for several microgrids in the Chicagoland area, it nevertheless set aside hundreds of millions of dollars for wind and solar development, particularly in low-income areas. Just a few months after the bill’s passage, the Illinois Commerce Commission, which regulates the state’s utilities, launched NextGrid, a statewide, collaborative study of the future of utilities.

Despite the hefty price tag of these updates to the grid, consumer groups have largely embraced them, hoping that investment in aging infrastructure today will pay dividends in the future.

“The energy industry is undergoing dramatic changes, and we need to make sure that consumer value is maximized,” Dave Kolata, executive director of the Citizens Utility Board, said in a statement in response to the launching of NextGrid. “This is an excellent opportunity to help lay the regulatory groundwork for an energy future that gives consumers the tools they need to take advantage of a more reliable and affordable electricity system.”

Comments are closed.