PECO Energy Co. on May 18 filed with the Pennsylvania Public Utility Commission a petition and application as the basis for its Microgrid Integrated Technology Pilot, in which the company would build, own and operate a community microgrid in Concord Township, Pa.
PECO requested that the PUC approve the pilot and issue a declaratory order that the company may seek to recover the costs of the pilot that are not recoverable through its electric distribution system improvement charge in a future distribution base rate case.
Under the pilot, the company is proposing to build, own and operate several distributed energy resource technologies to power the proposed microgrid, including natural gas engines.
PECO added that it is exploring emerging microgrid technology investment opportunities to enhance system reliability, resiliency and security as envisioned under the company’s electric long-term infrastructure improvement plan. PECO said that the community microgrid would be integrated with the company’s distribution system.
The project would focus on improving the distribution system’s ability to sustain and recover from adverse events – including severe weather – and on providing reliable access to essential services during power outages. The company added that the resulting information would be shared with the PUC and other stakeholders to facilitate the successful deployment of additional microgrids and DERs in the state.
The proposed microgrid would be comprised of six major components: distribution infrastructure; the microgrid controller; the communications network; DERs; switching, isolation and control equipment; and the information technology systems.
PECO added that it would examine various microgrid research and development issues, including the feasibility of integrating microgrid technology with the distribution system and expanded microgrid capabilities and applications, such as integration of customer-owned DER.
To select its proposed microgrid pilot site in Concord Township, PECO said that it used a three-step process. First, the company conducted a scoping process to identify prospective locations with the opportunity to enhance reliability and resiliency capabilities and support critical government facilities and public accommodations during major disruptions to PECO’s distribution system.
Next, the company said that it retained Quanta Technology to evaluate the potential for microgrid deployment at four prospective sites identified through PECO’s scoping process. Lastly, PECO said that it evaluated Quanta’s feasibility analysis and selected Concord Township from among the four finalists as the site for the microgrid.
Under the conceptual design developed by Quanta, PECO said that it is proposing two integrated microgrids to support a footprint of about 388 acres in a high density area of Concord Township with various essential public service loads, including local emergency services, to form a microgrid capable of supplying power to three critical government facilities and 27 public accommodations with a typical aggregate peak load of 8.6 MW.
Under the plan, PECO said that it proposes to install the microgrid controller to operate the Concord Township microgrids during grid-connected and island modes and during the transition period between those modes.
The microgrid controller receives real-time data from distribution equipment, metering equipment and DERs to identify voltage, capacity and load on the microgrid and PECO’s distribution system. PECO added that a key functionality of the microgrid controller is the ability to automatically operate DERs and configure switchgear to maintain or restore energy to the Concord Township Project in the event of power loss or interruption on PECO’s system.
The Concord Township Project would be powered by various DER technologies, the company said, adding that it proposes to initially install and test natural gas reciprocating engines, ground-mounted solar photovoltaic (PV) installations, two batteries and four dual-port electric vehicle (EV) charging stations.
The use of natural gas reciprocating engines ensures that the microgrid would have sufficient generation to meet typical customer peak load during an outage at all times, with the 500 kW of solar PV and 200 kW of batteries included to investigate the use of intermittent resources and storage in microgrid operation, PECO said. The batteries would also be available to provide uninterruptible power supply to critical government facilities, the company said.
When operating in island mode, the project would be able to provide uninterrupted service to the Concordville fire station and Township building within the project’s boundaries and is expected to restore power within 15 minutes to other services and customers within the microgrid, PECO said.
Discussing its implementation plan, PECO said that it proposes to begin initial work on the microgrid pilot, including engineering and design studies, as soon as practicable after PUC approval of the plan.
PECO said that it anticipates that such initial work would be completed by 2018, and the company would then build, install, test and commission the project, with operations beginning in 2020.
PECO said that to procure the microgrid controller, communications network, IT systems, switching, isolation and control equipment, as well as the DER components of the microgrid, it would use a structured competitive vendor selection and contracting process, which contemplates one or more requests for proposals (RFP) to select its microgrid technology, vendors and project developers.
The Concord Township Project microgrid would operate in one of two modes in response to system conditions, the company said, noting that during times of outages and other service disruptions, the microgrid would transition to island mode. PECO said that it anticipates that the project would be in island mode for about 28 hours per year, and at all other times, the project would be connected to the grid.
During grid-connected mode, the DERs owned by PECO are expected to participate in PJM Interconnection wholesale markets when it is economic to do so and would not be used to provide default service supply, the company said. The net proceeds from any PJM wholesale market transactions involving the DERs would be flowed back to PECO distribution customers.
The company noted that the PUC last October approved PECO’s electric LTIIP to invest an additional $274 million over a five-year period – 2016 through 2020 – for infrastructure improvements designed to enhance reliability by strengthening and modernizing PECO’s electric distribution system.
The company estimates that the costs to implement the preliminary base design would be about $35 million. PECO added that the microgrid pilot costs fall into three categories, including the annual operation and maintenance (O&M) expense.
The company said that it proposes to recover those costs from all customers as the project would provide insight into the future deployment of microgrids and integration of DERs across PECO’s service territory, and thereby benefit all PECO customers. PECO added that it estimates the costs of an upgraded microgrid design to be about $13 million, which may be reduced through participation of customer or third-party DERs sited on customer property.
The company said that it proposes to recover plan costs through two different mechanisms. PECO would seek to recover the costs incurred to repair, improve or replace property that is part of the company’s distribution system totaling about $15.3 million, along with the company’s other electric LTIIP investments approved by the PUC in another docket, through the company’s DSIC.
The costs that PECO proposes to initially recover through its DSIC would be rolled into base rates in a subsequent base rate case, at which point the DSIC would be reset to zero.
The company also said that it proposes to recover the remaining plan costs of implementing the preliminary base design, totaling about $19.6 million and consisting primarily of DERs on PECO property that will power the proposed microgrids and related information technology systems, communications networks and control equipment and annual operating and maintenance expense, in a subsequent electric distribution base rate case.
Among other things, PECO noted that its proposed procedural schedule calls for a PUC order next February.