Contrary to a recent report that coal-generated electricity prevented a system collapse during January’s “bomb cyclone” deep freeze, PJM Interconnection, the regional transmission organization of which Virginia is a part, says it had plenty of reserve capacity. The reason PJM dispatched so much electricity from coal-fired units was that it was cheaper than electricity generated by natural gas, the price of which surged during the cold spell — not because there were inadequate supplies of gas.
“Natural gas and nuclear units were not unreliable or otherwise unavailable to serve increased customer demand, nor would PJM have faced ‘interconnected-wide blacksouts’ without the particular generating units dispatched, states PJM in a response forwarded to U.S. Energy Secretary Rick Perry. (Hat tip: Albert C. Pollard, Jr.)
Last week Bacon’s Rebellion summarized key findings of a report by the National Energy Technology Laboratory (see “How Coal Saved the Electric Grid,”) which noted that coal-fired generation increased dramatically during the extreme, 12-day chill. Nuclear energy output didn’t change (nukes run flat-out all the time, regardless), wind/solar output declined slightly, and gas output was constrained by pipeline constraints and other factors. The NETL report argued that without the backup coal capacity, “a 9-18 GW shortfall would have developed, depending on assumed imports and generation outages, leading to system collapse.”
But PJM says that the regional electricity transmission system maintained significant reserves during the bomb cyclone. “PJM reserves were over 23 percent of peak load demand, and there were few units that were unable to obtain natural gas transportation.” The reason coal-fired output leaped was that it was cheaper than gas — not that the gas was unavailable.
During the cold snap, the region experienced an increase in the price of natural gas, which made coal resources (which often did not run under periods of lower natural gas prices) the more economic choice during times of high gas prices. But one cannot extrapolate from these economic facts a conclusion as to future reliability within PJM. …
The fact that additional coal resources were dispatched due to economics is not a basis to conclude that natural gas resources were not available to meet PJM system demands or that without the coal resources during this period the PJM grid would have faced “shortfalls leading to interconnect-wide blackouts.”
The PJM report did confirm other parts of the NETL analysis. Electricity from nuclear power plants stayed constant through the 12-day weather event. Wind and solar output declined ever-so-slightly. And natural gas did suffer minor supply-related outages… but they accounted for less than 2% of the total load requirement at the time.
Bacon’s bottom line: Coal-fired units kicked in 13,000 megawatts of additional output during the deep freeze. That was roughly one-third of the system’s 32,600 megawatts in reserve capacity. In the absence of the coal surge, customers in Virginia and across the multi-state PJM system would have paid more for their natural gas, but they would not have faced blackouts in January. It seems safe to say that the impression created by the NETL analysis was wrong.
But PJM did not address the longer-term outlook in its report. The political reality is that in the U.S. and in Virginia, powerful interest groups seek to curtail coal production. There is a strong likelihood that Virginia will enter the Regional Greenhouse Gas Initiative, a cap-and-trade arrangement designed to cut carbon emissions, most likely through the closure of additional coal plants. Looking out a decade or more, some environmental and consumer groups oppose the plans of Dominion Energy Virginia to re-license its four nuclear power units that currently produce 30% of the company’s electric power. Furthermore, the same groups, worried by the contribution of natural gas to CO2 emissions, want to slam the door on construction of any more gas-fired power plants.
As can be seen in the chart above, which details the breakdown of electricity by fuel type in the PJM system before and during the deep freeze, coal and nuclear accounted for 65% of the interstate region’s electricity production before the event and 66% during the cold snap.
Put another way, coal accounted for 45,900 megawatts of system-wide output during the freeze, and nuclear contributed another 35,400. Compare that to the system’s 32,6oo megawatts in reserve capacity.
While PJM has plenty of reserve capacity today, we have to ask ourselves, will the system have plenty of reserve capacity 10 or 15 years from now if coal- and nuclear-powered units continue to shut down? While the pipeline capacity exists today to supply today’s natural gas demand, will it be sufficient to meet demand when gas picks up much of the load for shuttered coal and nukes? While we can always purchase out-of-state electricity through PJM, will there be sufficient transmission-line capacity to get that electricity to Virginia load centers?
I don’t know the answers to these questions. Perhaps everything will turn out fine. But we can’t assume that it will just because PJM has ample reserve capacity today. As Virginians calibrate the balance between coal, nuclear, gas, hydro, solar, wind and battery storage, we need to consider the long-term outlook. The future will be upon us before we know it.
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