Maintaining grid reliability across the North American bulk power system could prove challenging this summer if the coronavirus pandemic continues into that season or beyond, the North American Electric Reliability Corp. said in an April 23 report.

Grid operators are already fending off increased cybersecurity attacks and managing COVID-19-related staffing challenges, NERC explained. Additional issues that could "lead to constraints over the summer" include shortages in supply chain materials, delayed maintenance outages, and changes in demand levels from industrial customers coupled with increased proportions of rooftop solar projects injecting power onto the grid, NERC said in the report.

"These aren't sky-is-falling reliability risks," NERC Director of Reliability Assessment and System Analysis John Moura said in a press call on the report. "But when you have changes on the system, it affects other parts of the system."

Grid operators, for example, are uncertain about projected demand and their daily electric profiles. Whereas, for example, grid operators could previously count on major manufacturing facilities to act as anchors along the grid to help with reactive power support, many of those customers are offline because of the coronavirus, Moura explained.

"These are operating conditions we've never seen before," Moura said. He added that a failure to perform routine maintenance on projects could also increase the risk of those facilities having "forced outages" later on.

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The report also indicated system operators have had challenges getting virus test kits for key personnel, which makes some operators hesitant to sequester staff together for fear of putting those workers at increased risk.

NERC noted, however, that the coronavirus currently poses no specific threat nor has it led to the degradation of the reliable operation of the bulk power system.

Moura attributed the performance of the grid so far to decades of industry emergency preparation and related drills. But he acknowledged that the fundamental risk from the coronavirus is unusual compared to normal reliability risks because it relates primarily to the loss, or efforts to prevent the loss, of critical staff.

NERC in March asked utilities, reliability coordinators and other jurisdictional entities to outline their preparedness for a potential coronavirus epidemic emergency and their capacity to offer aid to other industry participants if those areas are hit harder.

The responses from those entities show that most, but not all, organizations had a pandemic plan, the report said. For those that did not have a report, NERC provided an anonymized plan that they could replicate. The ERO is now creating an enhanced version that it intends to distribute to the whole industry.

More than half of registered entities also indicated to NERC that they would be able to support mutual aid requests for help, and a large majority of entities said they have reviewed their supply chain needs.

On the press call, Matt Duncan, Electricity Information Sharing and Analysis Center senior manager of resilience and policy coordination, said the primary materials entities are having trouble getting their hands on include chemicals, masks, gloves, fire-resistant rated clothing, plastic coverings for keyboards and laptops. Moura reported that no major grid infrastructure equipment supply problems have occurred.

Another concern mentioned in the report is what will happen if nuclear power plants delay their refueling until after the pandemic passes due to staffing issues. In 2020, reactors at 56 U.S. nuclear plants are scheduled for refueling, the report said. But many of the workers who handle the refueling are contractors and go from one refueling project to the next, which increases the risk of spreading the virus. Moreover, if one plant delays its refueling, doing so could make it harder for other projects in the queue to keep to their original refueling schedule.

NERC has also moved to ease the regulatory burden on entities during the pandemic. For example, the Federal Energy Regulatory Commission recently granted NERC's request to delay until Oct. 1 the implementation of the three critical infrastructure protection standards and for six months the implementation of four other mandatory reliability standards that were set to become effective or phased in during the second half of 2020.