A cleaner grid is a more reliable, resilient grid

Andy Johnson is executive director of Clean Energy Districts of Iowa, which was first to publish this commentary.

The June 2 print edition of the Des Moines Register led with the headline, “Iowans warned of rolling blackouts.” Utility sources quoted in the article repeatedly tried to connect the growth of renewable energy with a less reliable grid.

As Mark Twain said: “Few things are more irritating than when someone who is wrong is also very effective in making his point.” Sure, it sounds sensible that closing “baseload” coal plants and replacing them with “variable” renewables is a recipe for disaster. But that logic actually mixes apples and oranges—or corn and beans, or uff-da: 4-H and Future Farmers of America!

Here’s why we can’t blame renewables for the current grid challenges. In fact, the opposite is true: a clean energy future is the best recipe for a healthy, wealthy Iowa and a reliable, affordable grid.

First, a clarification: neither the grid’s regional Midcontinent Independent System Operator (MISO) nor the North American Electric Reliability Council (NERC) are actually predicting blackouts this summer. The media is sounding alarms based on a recent NERC report (1), but NERC gets its data from MISO.

MISO’s data clearly show (2) that under the most likely scenarios of predicted generation and peak summer usage, there will be a 6 to 11 percent operating reserve (available surplus) for each summer month. Only under the extreme conditions of extreme peak demand, combined with extreme power plant outages, does the region face shortfalls of 1.4 to 5.8 percent. It is critically important to know and to plan for the worst case scenario, but it is not actually the projected outcome of grid operators for this summer.

According to MISO data (3), while summer demand is predicted to rise slightly over a year ago, “firm” generation resources (coal, natural gas, and nuclear) are predicted to rise even more. This is important enough to repeat (4): fossil fuel generation resources committed to meeting peak demand within the MISO region are actually higher for the summer of 2022 than for the summer of 2021.

So what’s really causing the potential power shortages? There are two answers, and they should open our eyes to the importance of moving away from fossil fuels and towards clean grid solutions.

First, coal and natural gas power plants are becoming significantly less reliable, especially during high demand periods.

The potential for fossil fuel power plant shutdowns during peak summer months grew dramatically from the 2021 to 2022 forecasts: in fact, nearly a quarter of this generation capacity could be offline when it’s needed most (5). Grid operators say these growing fossil fuel plant outages are due to a combination of volatile and insecure fuel supply, aging plants, and failures during extreme weather – in other words, fossil fuel generation is becoming less stable and predictable (and more expensive) every year.

The growth in predicted 2022 worst-case fossil fuel plant outages alone (about 6 Gigawatts) actually accounts for the entire shortfall in worst-case summer 2022 power supply in the MISO region (6).

The second major cause of potential grid challenges this summer, according to the MISO data, is climate change—caused by the very over-reliance on fossil fuel combustion that fossil fuel execs and some utilities continue to say we need more of.

Remember, a worst case scenario for the grid is a combination of unacceptably low power generation and extremely high demand. As discussed, high levels of fossil fuel plant outages create the risk for unacceptably low generation. Extremely high demand, on the other hand, is a direct result of widespread heat waves and drought.

According to the NERC report, “Above average seasonal temperatures can contribute to high peak demand as well as increases in forced outages for generation.” (7) Not only is climate change driving up our air conditioning demand, it’s driving down the reliability of fossil fuel plants, and even hydroelectric generation. Extreme temperatures also contribute to the power plant outages discussed above.

NERC goes on to state, “In the unlikely event that multiple [grid regions] are experiencing energy emergencies as could occur in a wide-area heatwave, some transfers may be at risk of not being fulfilled.” (8) In other words, climate change directly stresses the grid and reduces the ability for grid regions to support each other with surplus power flows.

This reality is also directly reflected in the MISO data submitted to NERC, which shows a decrease of over 50% in potential power transfers from other grid regions in MISO’s worst case scenario (9). The drop of over 1.6 Gigawatts from summer 2021 to 2022 is more than the entire decrease in the MISO “anticipated reserve margin” (10), and the bulk of the potential worst-case summer power deficit.

It’s clear: fossil fueled power generation is becoming less reliable, and is driving climate change. Climate change is driving more extreme levels of power demand, and directly contributing to less reliable fossil fuel plants, supply chains, and grid operation.

More (or longer running) fossil fuel power generation isn’t the solution, it’s the problem. But where do we go from here?

Contrary to the fossil fuel industry’s insistence that only coal and natural gas can provide “baseload,” and renewables are “variable,” the energy grid has always been about matching supply and demand in a predictable manner. Utility “demand response” programs have languished, there is tremendous potential for innovation on the demand side of the supply-demand equation, at both the distribution and transmission levels.

If fact, a coalition of MISO transmission customers has recently proposed that MISO adjust its rules and tariff to allow customers capable of shedding load during grid emergencies to do so without price penalties (11). Their combined demand reduction potential alone represents more than the MISO projected shortfall in most worst-case scenarios.

Renewable energy is variable, but also increasingly predictable in that variability (more predictable, in fact, than fossil fuel plant outages). Solar energy has a 50 percent “capacity rating” in MISO (12), meaning that on the grid level, half of all installed solar can be predictably and reliably expected to be contributing to power needs during summer peak demand (because peak demand happens during heat waves).

We urgently need more utility-scale solar energy at the distribution and transmission levels throughout Iowa and the Midwest. And we need to rapidly scale up utility scale battery storage (already cost-competitive with natural gas peaking plants, and getting cheaper every year), to hold surplus wind and solar for the hours of greatest grid demand.

Finally, as the grid transitions from increasingly unreliable and expensive fossil fuels to increasingly reliable and inexpensive renewable energy, we most certainly need more and better high voltage transmission to move energy where it’s needed, when it’s needed. Transmission costs money and requires regulatory support, but the returns to Iowans in a more reliable and resilient grid, and cleaner and more affordable energy, will be more than worth it.

It’s time for a change of thinking in Iowa. Time for a new vision for the grid, with local and state investment and jobs, a clean and reliable resource mix, and an attention to climate stewardship that will make our kids proud, and their communities strong.

Iowa’s energy future is bright—if we’re open and committed to building it.


End Notes:

  1.  2022 Summer Reliability Assessment, North American Electric Reliability Corporation, May 2022; (https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/NERC_SRA_2022.pdf
  2.  Seasonal Assessment – Generation Summer 2022, MISO, spring 2022; p11, bottom two rows (https://cdn.misoenergy.org/2022%20Summer%20Resource%20Assessment624718.pdf
  3.  2022 Summer Reliability Assessment, North American Electric Reliability Corporation, May 2022; p40, “MISO Resource Adequacy Table”, Net Internal Demand and Existing-Certain Capacity rows (https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/NERC_SRA_2022.pdf)
  4.  2022/23 Planning Resource Auction (PRA) Results, Midcontinent Independent System Operator, April 14, 2022; slide 21 (https://cdn.misoenergy.org/2022%20PRA%20Results624053.pdf
  5.  Seasonal Assessment – Generation Summer 2022, MISO, spring 2022; p5, the “Jun-21” bar is used in 2022 worst case scenario for outages, and is ~6 GW higher than the previous peak outage from “Jun-20”. Peak outages are steadily rising for years; (https://cdn.misoenergy.org/2022%20Summer%20Resource%20Assessment624718.pdf
  6.  Ibid; last row, worst case scenario is July, with 5.8 GW deficit
  7.  2022 Summer Reliability Assessment, North American Electric Reliability Corporation, May 2022; p7; (https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/NERC_SRA_2022.pdf)
  8.  Ibid, p13
  9.  Ibid, p40, MISO table, Net Firm Capacity Transfers row
  10.  Ibid, p40, MISO table, Anticipated Reserve Margin row
  11.  MISO industrial customers petition FERC to avoid sky-high capacity charges if they cut electricity use, Utility Dive, May 27, 2022; (https://www.utilitydive.com/news/miso-industrial-customers-capacity-FERC-complaint/624524/)  
  12. 2022 Summer Reliability Assessment, North American Electric Reliability Corporation, May 2022; P46, first (MISO) row, “Solar – Expected Share of Nameplate (%)” column; (https://www.nerc.com/pa/RAPA/ra/Reliability%20Assessments%20DL/NERC_SRA_2022.pdf)

Top illustration of energy storage system involving renewables was created by petrmalinak and is available via Shutterstock.

About the Author(s)

Andy Johnson

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