Hunkered down in the PJM Interconnection operations center near Valley Forge, Pa., shift supervisor Brian Oakes waited for a distress call.
A mass of Arctic air was descending on the Eastern Seaboard, and Oakes would be the first to know if there was an emergency to tend to in the glowing map of power plants and transmission lines splayed before him.
The call never came.
Instead, PJM's grid — an intricate machine spanning 13 Eastern states and the District of Columbia — sped along without a hitch despite cratering temperatures that would eventually be blamed for more than two dozen deaths.
Oakes knew why.
More gas units had cropped up inside PJM's footprint and across the shadow of the Marcellus Shale natural gas play. Additional transmission lines and new substations had been built to account for coal and nuclear plant closures. Oakes saw a system with deep reserves of natural gas, coal and hydropower.
Staff members in PJM's nerve center had increased their training hours. And equipment across PJM's footprint had been hardened and protected since the deep freeze of 2014.
Oakes' reality stood in sharp contrast to the dire warnings the Trump administration and coal boosters had voiced in recent months, calling for immediate policy changes in the face of looming coal and nuclear plant closures.
Those calls fell flat last night as the Federal Energy Regulatory Commission rejected Energy Secretary Rick Perry's call for coal and nuclear lifelines, opting instead to launch a probe into grid operators' concerns and the definition of "resilience" (E&E News PM, Jan. 8). PJM and other grid overseers have 60 days to reply.
In its decision, FERC cited PJM's own study released in March that found reliability could be maintained even in the face of additional coal and nuclear retirements.
"Even with a high penetration of gas, we still are going to be a very reliable system," said Ken Seiler, executive director of PJM's systems operations.
Six hours west in Ohio, a diverging view emerged. David Ball, managing director of American Electric Power Co. Inc.'s transmission operation center in New Albany, also saw no signs of severe stress as temperatures plunged. He also credited additional transmission and capacity upgrades made during the past three to four years amid a slew of coal plant retirements.
Yet when asked whether the system would fare just as well if more coal and nuclear plants had retired, Ball voiced concern.
"When your reserves go away at some of these coal-fired plants," he said, "it's going to be hard to make up those reserves with other fuel types or renewable generation."
Focus on grid operators
FERC's decision to move forward with a proceeding to "explore resilience issues" among regional transmission organizations and independent system operators puts the focus squarely on the nation's grid operators.
PJM's experience this past week is already providing an important snapshot as regulators proceed.
FERC put forth more than a dozen complex questions for grid overseers to answer, including questions about the definition of "resiliency" and assessments of "high-impact, low-frequency events."
One FERC commissioner, Democrat Richard Glick, pointed to the recent deep freeze in his concurrence to highlight reliability issues tied to coal and nuclear power, including the sudden shutdown of the Pilgrim Nuclear Power Station in Plymouth, Mass., and outages tied to coal plants. "In fact, initial reports indicate that coal-fired facilities accounted for nearly half of all forced outages in PJM during last week's period of extreme temperatures," Glick wrote.
For AEP and PJM operators, the importance of transmission upgrades and the addition of power generation close to load centers emerged as critical points.
"The system has evolved quite a bit in the past 10 to 12 years where we were primarily importing power from the West into the major load centers like New York, Philadelphia, Baltimore, Washington," PJM's Seiler said. "Now we have, because of the Marcellus and the shale gas, we have a lot of gas units distributed across the entire footprint."
Seiler also pointed to upgrades following the 2014 deep freeze, including placing thermal blankets on generators and instruments, placing windshields around transformers, and stationing heaters.
When asked about the uptick in the use of coal in PJM's footprint during the recent cold snap, Seiler said rising demand for gas for heating — and a subsequent rise in price — drove coal to emerge as more economical. During the first week of January, coal generation produced 39 percent of PJM's electricity, to 21 percent for natural gas. In the first week of October, by comparison, gas generation's share was 32 percent compared with 28 percent for coal.
"We didn't have anybody who couldn't get gas during this event," Seiler said. "It's just a matter of the economics, so it just drives the prices up on a temporary basis during extreme weather. We had plenty of gas available for us."
AEP's Ball also agreed the system must be upgraded to match shifting resources.
Just three years ago, AEP had warned the markets were failing to attract capital and becoming increasingly reliant on natural gas. AEP at the time was slated to retire more than 6,500 megawatts of coal-fired generation — mostly in mid-2015.
Since then, Ball said AEP doubled down on new transmission construction to match shifting resources.
"That's been an evolution here recently with a lot of the older coal-fired generation plants being retired, so we've had to be extremely proactive in changing lines and rebuilding connection points so we're able to keep up with the changing generation," he said.
In making a case for blanket subsidies for coal and nuclear plants, Energy Secretary Perry's proposal raised two kinds of threats.
Bitter cold weather like the 2014 polar vortex episode could disrupt gas pipeline deliveries to natural gas units and thus jeopardize grid reliability — the requirement to keep power running smoothly around the clock. Coal and nuclear plants with on-site fuel were insurance against that threat, DOE said.
Further, it argued that keeping open money-losing coal and nuclear plants was also essential for grid resilience, the ability to recover from a catastrophic outage from extraordinary causes, from a massive earthquake to a once-in-a-century solar storm to a synchronized cyberattack.
But PJM has argued that on-site fuel storage is not essential to reliability, and other options are available. And DOE has never made a sound case for Perry's proposal on resilience grounds, PJM said in a sharply worded defense of its energy markets, delivered to FERC in October (Energywire, Oct. 24, 2017).
PJM Vice President Craig Glazer and associate general counsel Jennifer Tribulski wrote that as the mix of generation in its territory moves toward gas and renewables, with less coal-fired and nuclear power, the downsides are a reduction in stability resources such as voltage support, as well as fuel assurance.
But the newer power units permit faster, more flexible response to outages, citing the report PJM released in March. "Operational reliability can be maintained even if natural gas-fired resources replaced all coal-fired and nuclear generation resources," PJM said.
Glazer and Tribulski contended that DOE "assumes without support that there is a resilience crisis that is urgently unfolding because coal and nuclear units are retiring, that market prices are to blame, and that the only solution is to incentivize those coal and nuclear units to remain in service by providing them with guaranteed cost of service rate recovery regardless of whether they are needed for resilience or actually provide measurable resilience benefits."
While secure fuel supplies and a mix of generation contribute to both reliability and resilience, DOE never defined the latter issue or analyzed the advantages of different fuels in such emergencies, they said.
"[DOE] does not explain how maintaining a 90-day supply of fuel will enable quick restoration of service following a catastrophic grid event, which is a cornerstone concept of resilience," said the PJM officials. "Instead, the proposal seeks to keep coal and nuclear units online all the time as baseload resources."
What DOE is really talking about is reliability, they said.
"Neither the 2014 Polar Vortex nor the recent hurricanes justify upending existing competitive energy markets," they said. "Indeed, as the  DOE Staff Report acknowledges, during the Polar Vortex, [m]any coal plants could not operate due to conveyor belts and coal piles freezing."
The various extreme "black sky" emergencies in grid strategists' scenarios could challenge or disable different kinds of generation and power line networks in different ways. Depending on the situation, defenses could include more gas storage, advanced transmission technologies, integrated distributed energy supplies and shielding of vital equipment from solar storms.
PJM said it is examining what those threats require (Energywire, Dec. 4, 2017).
"Yes, fuel diversity within a region or market is important for resilience," the organization said. "PJM's resource portfolio is more diverse today than ever before, and the PJM region is less dependent on any single fuel type than other regions of the country," PJM said, adding that it will continue to investigate fuel diversity issues.