Will Shuttering Coal Plants Really Threaten the Grid?

Photo: Luke Sharrett/Bloomberg/Getty Images
Emissions rise as a U.S. flag flies at the American Electric Power Co. Inc. coal-fired John E. Amos Power Plant in Winfield, West Virginia.

Does President Obama’s plan to squelch carbon emissions from coal-fired power plants really threaten the stability of the grid? That politically-charged question is scheduled for a high-profile airing today at a meeting in Washington to be telecast live starting at 9 am ET from the Federal Energy Regulatory Commission (FERC). 

Such “technical meetings” at FERC are usually pretty dry affairs. But this one could be unusually colorful, presenting starkly conflicting views of lower-carbon living, judging from written remarks submitted by panelists

On one side are some state officials opposed to the EPA Clean Power Plan, which aims to cut U.S. power sector emissions 30 percent by 2030 from 2005 levels. Susan Bitter Smith, Arizona's top public utilities regulator, argues that EPA's plan is "seriously jeopardizing grid reliability." Complying with it would, she writes, cause “irreparable disruption” to Arizona’s (coal-dependent) power system.

Environmental advocates and renewable energy interests will be hitting back, challenging the credibility of worrisome grid studies wielded by Bitter Smith and other EPA critics. Some come from organizations that are supposed to be neutral arbiters of grid operation, such as the standards-setting North American Electric Reliability Corporation (NERC). Clean energy advocates see evidence of bias and fear-mongering in these studies, and they are asking FERC to step in to assure the transparency and neutrality of future analyses.

The reliability controversy began throwing off sparks in October and November 2014 when NERC and some regional transmission operators sent initial feedback to EPA on its June 2014 proposal (to be finalized this July or August). The early feedback assumed that state compliance plans would force tens of gigawatts (GW) of coal-fired power generation offline almost overnight with little action to compensate for the lost energy and grid regulation services. Not surprisingly, the studies described a pretty wobbly power grid. 

An October 2014 reliability assessment released by the Southwest Power Pool, the grid manager for nine central states, assumed that 9 GW of its region's coal-fired generation would close by 2020. The resulting power flows, SPP found, were so irregular that its simulation software was incapable of modeling them. This indicated, according to SPP, "voltage collapse and blackout conditions." 

NERC's initial assessment, issued in November, foresaw rolling blackouts and increased potential for "wide-scale, uncontrolled outages."

One energy lawyer writing in the utilities news site EnergyCentral compared the grid experts issuing these blackout warnings to Paul Revere sending his storied light signals and saddling up to make history.

Critics, however, cried foul. European grid operators already deliver power more reliably than their U.S. counterparts while displacing conventional power plants with high levels of renewable energy. And worst case scenarios such as NERC and SPP’s flew in the face of prior detailed U.S. grid studies showing it capable of following the Europeans’ lead.

John Moore, a senior attorney for the Natural Resources Defense Council who represents a coalition of environmental groups at today's FERC meeting, cites a 2013 study of coal reductions on Texas' grid by the Cambridge, MA-based Brattle Group. Brattle’s simulations found no reliability impact, even in scenarios where most of its coal-fired generation was shuttered and renewables met over 40 percent of demand.

Moore argues that NERC and SPP systematically ignored the flexibility and multiple compliance options that EPA’s Clean Power Plan offers to states. For example, the plan requires states to deliver interim CO2-reductions over the decade that begins in 2020, not by 2020.

Rob Gramlich, senior vice president for government affairs at the American Wind Energy Association, says the studies ignored modern wind farms’ capacity to deliver the grid regulation that conventional plants currently provide. As he puts it in his written comments: "Some analyses being done are truly 'garbage-in/garbage-out' exercises using outdated assumptions about clean energy.”

The enhanced capabilities of wind power plants are quickly spreading to solar power plants. In fact, even rooftop solar systems are getting upgraded inverters that can help grids ride-through frequency and voltage faults and even dynamically regulate grid voltage.

Both Moore and Gramlich call on FERC—which oversees NERC and the regional grid operatorsto ensure that these organizations’ grid studies are transparent, neutral and authoritative. "FERC needs to make sure... that NERC’s and the regional authorities’ studies do not unduly represent the interests of a particular segment of the electric power industry," writes Gramlich in a thinly-veiled reference to the coal sector. 

U.S. Department of Energy’s representatives will also have EPA’s back today, bearing a freshly-released report that has “shot down a key argument against President Obama’s climate plans” according to the Washington Post. The report suggests that natural gas infrastructure can easily supply plenty of natural gas to replace shuttered coal-fired generation.

DOE’s optimism rests on the fact that gas production is now more widely distributed across the country, as well as the potential to boost throughput in existing pipelines. As a result even high gas demand cases can be met by adding new gas pipelines over the next 15 years no faster than was achieved by 1998 through 2013. 

Grid operators may be yielding under the pushback and accusations of bias. The prepared remarks for NERC's CEO argue that "deeper assessment is needed to determine the time requirements and potential risks to reliability" posed by EPA’s plan. Talk of blackouts is gone, replaced by a promise to issue more detailed assessments in the months ahead. 

If there is an area where most of the parties agree, it is that expanded grid capacity to share renewable energy within or even between regions will be one of the keys to slashing power sector carbon emissions. Look for talk today about how FERC can cajole or command states and utilities to work together to get lines built. 

Failure to build new transmission may not black-out the grid, but most studies suggest that it will drive up the cost of compliance. When the wind blows, the resulting power needs a place to go, and the bigger the area it can serve the lower the likelihood that it will be wasted. 

Transmission experts would like to see the U.S. add long-distance high-voltage direct current (HVDC) lines of the sort that Germany, Norway and China are building, or even extra-high-voltage AC lines overlaid on the existing grid. The problem is getting all of the grid players who benefit to pay a share of the costs, says Gramlich. 

Gramlich says recent interstate capacity expansions in SPP’s territory and in the Midwest show that the U.S. power industry is figuring out how to get states to cooperate on regional lines. He credits regional transmission planning initiatives mandated by FERC, and recent court victories that show FERC has the authority to drive through new transmission—powers that FERC must now use to drive inter-regional transmission lines. As he writes in his statement: “FERC must not hesitate to use this authority.”


Newsletter Sign Up

Sign up for the EnergyWise newsletter and get biweekly news on the power & energy industry, green technology, and conservation delivered directly to your inbox.