Will Shuttering Coal Plants Really Threaten the Grid?

Grid studies claiming EPA's coal power rule could destabilize transmission systems amount to "garbage" science, according to renewable energy advocates

4 min read
Will Shuttering Coal Plants Really Threaten the Grid?
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.
Photo: Luke Sharrett/Bloomberg/Getty Images

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 EnergyCentralcompared 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.”

The Conversation (0)
This photograph shows a car with the words “We Drive Solar” on the door, connected to a charging station. A windmill can be seen in the background.

The Dutch city of Utrecht is embracing vehicle-to-grid technology, an example of which is shown here—an EV connected to a bidirectional charger. The historic Rijn en Zon windmill provides a fitting background for this scene.

We Drive Solar

Hundreds of charging stations for electric vehicles dot Utrecht’s urban landscape in the Netherlands like little electric mushrooms. Unlike those you may have grown accustomed to seeing, many of these stations don’t just charge electric cars—they can also send power from vehicle batteries to the local utility grid for use by homes and businesses.

Debates over the feasibility and value of such vehicle-to-grid technology go back decades. Those arguments are not yet settled. But big automakers like Volkswagen, Nissan, and Hyundai have moved to produce the kinds of cars that can use such bidirectional chargers—alongside similar vehicle-to-home technology, whereby your car can power your house, say, during a blackout, as promoted by Ford with its new F-150 Lightning. Given the rapid uptake of electric vehicles, many people are thinking hard about how to make the best use of all that rolling battery power.

The number of charging stations in Utrecht has risen sharply over the past decade.

“People are buying more and more electric cars,” says Eerenberg, the alderman. City officials noticed a surge in such purchases in recent years, only to hear complaints from Utrechters that they then had to go through a long application process to have a charger installed where they could use it. Eerenberg, a computer scientist by training, is still working to unwind these knots. He realizes that the city has to go faster if it is to meet the Dutch government’s mandate for all new cars to be zero-emission in eight years.

The amount of energy being used to charge EVs in Utrecht has skyrocketed in recent years.

Although similar mandates to put more zero-emission vehicles on the road in New York and California failed in the past, the pressure for vehicle electrification is higher now. And Utrecht city officials want to get ahead of demand for greener transportation solutions. This is a city that just built a central underground parking garage for 12,500 bicycles and spent years digging up a freeway that ran through the center of town, replacing it with a canal in the name of clean air and healthy urban living.

A driving force in shaping these changes is Matthijs Kok, the city’s energy-transition manager. He took me on a tour—by bicycle, naturally—of Utrecht’s new green infrastructure, pointing to some recent additions, like a stationary battery designed to store solar energy from the many panels slated for installation at a local public housing development.

This map of Utrecht shows the city’s EV-charging infrastructure. Orange dots are the locations of existing charging stations; red dots denote charging stations under development. Green dots are possible sites for future charging stations.

“This is why we all do it,” Kok says, stepping away from his propped-up bike and pointing to a brick shed that houses a 400-kilowatt transformer. These transformers are the final link in the chain that runs from the power-generating plant to high-tension wires to medium-voltage substations to low-voltage transformers to people’s kitchens.

There are thousands of these transformers in a typical city. But if too many electric cars in one area need charging, transformers like this can easily become overloaded. Bidirectional charging promises to ease such problems.

Kok works with others in city government to compile data and create maps, dividing the city into neighborhoods. Each one is annotated with data on population, types of households, vehicles, and other data. Together with a contracted data-science group, and with input from ordinary citizens, they developed a policy-driven algorithm to help pick the best locations for new charging stations. The city also included incentives for deploying bidirectional chargers in its 10-year contracts with vehicle charge-station operators. So, in these chargers went.

Experts expect bidirectional charging to work particularly well for vehicles that are part of a fleet whose movements are predictable. In such cases, an operator can readily program when to charge and discharge a car’s battery.

We Drive Solar earns credit by sending battery power from its fleet to the local grid during times of peak demand and charges the cars’ batteries back up during off-peak hours. If it does that well, drivers don’t lose any range they might need when they pick up their cars. And these daily energy trades help to keep prices down for subscribers.

Encouraging car-sharing schemes like We Drive Solar appeals to Utrecht officials because of the struggle with parking—a chronic ailment common to most growing cities. A huge construction site near the Utrecht city center will soon add 10,000 new apartments. Additional housing is welcome, but 10,000 additional cars would not be. Planners want the ratio to be more like one car for every 10 households—and the amount of dedicated public parking in the new neighborhoods will reflect that goal.

This photograph shows four parked vehicles, each with the words \u201cWe Drive Solar\u201d prominently displayed, and each plugged into a charge point.Some of the cars available from We Drive Solar, including these Hyundai Ioniq 5s, are capable of bidirectional charging.We Drive Solar

Projections for the large-scale electrification of transportation in Europe are daunting. According to a Eurelectric/Deloitte report, there could be 50 million to 70 million electric vehicles in Europe by 2030, requiring several million new charging points, bidirectional or otherwise. Power-distribution grids will need hundreds of billions of euros in investment to support these new stations.

The morning before Eerenberg sat down with me at city hall to explain Utrecht’s charge-station planning algorithm, war broke out in Ukraine. Energy prices now strain many households to the breaking point. Gasoline has reached $6 a gallon (if not more) in some places in the United States. In Germany in mid-June, the driver of a modest VW Golf had to pay about €100 (more than $100) to fill the tank. In the U.K., utility bills shot up on average by more than 50 percent on the first of April.

The war upended energy policies across the European continent and around the world, focusing people’s attention on energy independence and security, and reinforcing policies already in motion, such as the creation of emission-free zones in city centers and the replacement of conventional cars with electric ones. How best to bring about the needed changes is often unclear, but modeling can help.

Nico Brinkel, who is working on his doctorate in Wilfried van Sark’s photovoltaics-integration lab at Utrecht University, focuses his models at the local level. In his calculations, he figures that, in and around Utrecht, low-voltage grid reinforcements cost about €17,000 per transformer and about €100,000 per kilometer of replacement cable. “If we are moving to a fully electrical system, if we’re adding a lot of wind energy, a lot of solar, a lot of heat pumps, a lot of electric vehicles…,” his voice trails off. “Our grid was not designed for this.”

But the electrical infrastructure will have to keep up. One of Brinkel’s studies suggests that if a good fraction of the EV chargers are bidirectional, such costs could be spread out in a more manageable way. “Ideally, I think it would be best if all of the new chargers were bidirectional,” he says. “The extra costs are not that high.”

Berg doesn’t need convincing. He has been thinking about what bidirectional charging offers the whole of the Netherlands. He figures that 1.5 million EVs with bidirectional capabilities—in a country of 8 million cars—would balance the national grid. “You could do anything with renewable energy then,” he says.

Seeing that his country is starting with just hundreds of cars capable of bidirectional charging, 1.5 million is a big number. But one day, the Dutch might actually get there.

This article appears in the August 2022 print issue as “A Road Test for Vehicle-to-Grid Tech.”

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