On-Site Power, Renewables

Bronzeville: Building the first utility-operated microgrid cluster

Microgrids are an important technological advance, but their implementation requires innovation too. In Illinois, ComEd had been leading the way by developing a better kind of microgrid controller, implementing innovative training programs, and even issuing a new kind of proposal to power it.

All of this is needed to make the first utility-operated microgrid cluster a success. Microgrids are electrically and physically defined portions of the grid which are powered by distributed energy resources (DER) like solar PV and energy storage, which can operate either independently, or as part of the larger grid. Experts spanning from the Department of Energy (DOE) to MIT have identified microgrids as a necessary technology to enhance the resiliency of the electric grid from threats ranging from major weather events to cyber-terrorism. In the aftermath of Hurricane Irma, for example, the Department of energy issues a report recommending microgrids as a way to mitigate such tragedies in the future.

Microgrid technology has already proven its value in the aftermath of the Fukushima nuclear event in Japan, when a small microgrid continued to provide power to a senior citizen center and a medical facility, and after Hurricane Sandy, when microgrids kept portions of two universities and a research center functioning even during the worst effects of the storm. But as the value of this technology becomes more apparent, and they are deployed in more diverse and challenging conditions, there remains need for much innovation in how to ensure that all of the possibilities of this technology become reality.

Leading Up to the Installation

On February 28, the Illinois Commerce Commission (ICC) approved ComEd’s plan to install the first utility-operated microgrid cluster. This 7.7 MW microgrid will provide service to approximately 770 customers in the Bronzeville neighborhood of Chicago, including the headquarters of the Chicago Police and Fire Departments. The site was selected after a holistic, data-driven effort to identify the portion of ComEd’s service territory that would most benefit from the incremental resiliency capabilities enabled by a microgrid.

ComEd committed to working with third parties to power the microgrid with different types of distributed energy resources (DER) including 750 kW of solar PV and 500 kW/2MWh of battery energy storage. These technologies are significant because they can reduce the reliance of the grid on high-carbon forms of generation like coal, while also supporting ComEd’s efforts to promote the integration of renewable DER. In 2016, ComEd was awarded a $4 million grant from the DOE to develop a technology that would support the integration of solar PV and energy storage within a microgrid, which will be demonstrated within the Bronzeville community microgrid and provide opportunities for solar developers.

Developing a Microgrid’s DER

After the order by its regulators was issued in February, ComEd began a series of workshops with non-vendor stakeholders to explain the project and opportunities to supply solar generation. Though the generation will be owned by a third party, ComEd issued a request for proposals through which it would purchase the distribution capacity associated with the generation so that it would be available locally to operate when the microgrid was in islanded or grid-connected mode. ComEd analyzed proposals to ensure they were technically viable to meet the load demand and selected a qualified bidder so that the solar PV can be installed and operational by the end of 2018.

The Brains of the Microgrid

Because solar PV’s generation is intermittent, or reliant on when the sun is shining to produce energy, storage becomes crucial. ComEd issued a second request for proposals for storage developers from which ComEd could purchase this resource that provides some of the dispatchability needed to meet the load, but also to complete its obligations under the Department of Energy grant.

These DERs would be utilized within the microgrid, particularly when it is in islanded mode, by a controller. In this microgrid, however, ComEd will install a microgrid master controller (MMC), which will allow it to not only operate the Bronzeville Community Microgrid, but also adjacent microgrids that are clustered to it. Using this technology, ComEd would be able to optimize the usage of resources like energy storage and demand response between the two microgrids, making them even more effective.

Innovation in the Microgrid

In May of 2018, ComEd subjected the MMC that was developed to a comprehensive set of over 300 tests, including planned islanding, accidental islanding and microgrid clustering, successfully completing the requirements for the grant.

These tests were conducted in the Grid of the Future Laboratory, which ComEd installed earlier this year as part of an effort to prepare for the increased deployment of innovative technologies. This lab includes real-time digital simulator (RTDS) racks, which can simulate electromagnetic transient events and can do control hardware in the loop (CHIL) as well as power hardware in the loop (PHIL) tests, which are invaluable for not only testing MMCs, but also the energy storage systems and smart inverters which will play an increasingly large role, both within and without the microgrid.

Leveraging the technological innovation of the MMC, ComEd is partnering with Siemens to integrate its algorithms into Siemens’ microgrid management system (MGMS), which will be able to implement control actions for both this microgrid project, but also other microgrid installations.

The Microgrid’s Impact

Though microgrids have been installed elsewhere before, there does not yet exist a widely accepted approach to quantify the benefits that they provide. As part of this project, ComEd committed to releasing annually data from dozens of metrics that would inform an initial benefit-cost analysis. Though the microgrid has yet to be installed, ComEd has already begun collecting baseline measurements to make it possible to identify the effects. Already, it has installed power quality meters within the footprint of where the microgrid will be to do just that.

All of the projects above require a workforce that is capable of implementing these technologies.  For six years, ComEd has been leading CONSTRUCT, which is a job training program that increased employment opportunities for minorities in Chicago and northern Illinois. Hundreds of students have undergone its nine-week program, which provides the training and information needed to compete for entry level positions in construction-related fields to install technologies like microgrids. As part of the Future Energy Jobs Act, an additional $30 million funding was secured to develop the workforce still further, particularly for solar pipeline training programs, craft apprenticeships, and multicultural training for individuals from diverse and/or underserved backgrounds. ComEd is even collaborating with HFS Scholars to develop an innovative program to help talented high school students in the Chicago area from underprivileged backgrounds complete a project to support their efforts to excel in the field of engineering.

These programs can be seen as adjacent to a broader vision for the Community of the Future, through which ComEd has been collaborating with partners and stakeholders in the Bronzeville neighborhood to demonstrate how smart grid technologies can support smart city solutions. To that end, ComEd has been looking to develop a future workforce in a variety of ways. For years, it has sponsored an Icebox Derby, in which dozens of girls work with ComEd engineers to repurpose old iceboxes into racing machines, demonstrating how engineering principles can produce real-world results. This year, ComEd sponsored its first Ideathon, in which high school students in Bronzeville collaborated with engineers from local companies to develop ideas that leverage the infrastructure of the Smart Grid to solve real-world problems.

Many of these participants won’t become ComEd engineers, or at least not right away. These programs, however, demonstrate a broader recognition that projects like the Bronzeville Community Microgrid represent just one brick in the longer-term foundation on which the electric grid of Northern Illinois, and the society that relies upon it, will ultimately flourish. This microgrid will be completed to deal with present challenges, but as conditions shift, with the effects of climate change leading to more and larger-impact major weather events, and the concerns with cyber and physical terrorism becoming ever more salient, the lessons that will be learned by this project will soon inform the design, development and operation of the entire distribution grid.