There is no doubt that climate change poses a serious threat to the reliability of America’s electricity grid. What may be less known, however—and often actively obfuscated by fossil fuel interests—is that renewable energy can not only mitigate the harms of climate change but also support a more resilient grid.
The climate crisis is here, and its destabilizing effects are threatening the grid.
The increasing frequency and intensity of extreme heat, wildfires, winter storms, hurricanes, and other extreme weather events is straining the grid, while also highlighting the vulnerabilities and lack of preparedness from conventional fossil fuel generation. As power outages have doubled over the past 20 years thanks to the increasing effects of climate change and extreme weather events, grid operators must plan for the future and enable the accelerated deployment of clean energy—reducing greenhouse gas emissions to tackle climate change while simultaneously improving the reliability and resiliency of the grid.
Fossil fuels are proving to be increasingly unreliable in the face of climate-induced extreme weather events
The status quo is not working; America’s fossil fuel-fired power fleet is becoming increasingly unreliable, causing outages and grid failures during extreme weather events. In fact, in its 2023 “State of Reliability” report, the North American Electric Reliability Corporation’s (NERC) first key finding was that conventional generation is experiencing its “highest level of unavailability” and facing severe reliability challenges, primarily due to poor performance of the gas fleet during extreme weather events and the increasing outage rates of coal-fired power plants. NERC also noted that “there are no apparent trends in the unavailability of the other forms of generation.” The coal and gas fleets are not sufficiently equipped to perform under extreme weather conditions.
America’s fossil fuel-fired power fleet is becoming increasingly unreliable, causing outages and grid failures during extreme weather events.
This trend was clearly on display during Winter Storm Elliott in December 2022, which knocked out electricity for millions of Americans in the eastern United States. PJM, one of the grid operators in the region, found that 70 percent of its forced outages were caused by failing gas plants and 16 percent were caused by coal. This is because gas plants face fuel supply and equipment failures from freezing temperatures; and while fossil fuel-fired power plants caused the vast majority of outages, wind resources performed well above their expected capacity during the storm. Grid operator Midcontinent Independent System Operator (MISO) also found that wind production remained high during the storm, providing support to the grid while gas plants caused shortfalls.
And it’s not just winter storms that pose threats to the fossil fleet; extreme heat also causes power plants to shut down or underperform. While Texas faced extreme heat waves this summer, coal and gas resources faced significantly higher outages than usual. Meanwhile, renewables supported almost half of the electricity demand in the state, meeting and exceeding forecasts. As the world faced its hottest summer on record and climate change continues to exacerbate extreme weather events, it’s crucial that grid operators pay attention to the vulnerabilities of conventional gas generation.
Using renewables, the United States can decarbonize and build out a clean, reliable electricity grid
To tackle climate change and clean up the power sector, the Biden administration has set a goal to achieve an 80 percent clean electricity grid by 2030. Fortunately, the United States doesn’t have to choose between decarbonization and reliability. Indeed, countless studies have proven that a clean grid is possible without compromising on grid reliability; resource adequacy—in short, balancing supply and demand across the grid—can be maintained by a decarbonized grid:
- A rigorous study conducted by University of California, Berkeley found that a 90 percent clean electricity grid would be achievable in 2035. In that analysis, energy demand was met in all periods, even with half of current existing fossil fuel capacity and complete coal retirement—including during extreme weather events and periods of low renewable energy generation.
- A study conducted by the National Renewable Energy Laboratory (NREL) found that an 80 percent clean electricity grid and high levels of wind, solar, storage, and other zero-carbon resources would maintain resource adequacy and balance the grid.
- Energy Innovation performed a comprehensive meta-analysis of 11 studies by leading researchers modeling the feasibility of achieving an 80 percent clean electricity grid, finding that across all 11 studies, a 70 to 90 percent clean electricity grid would be able to match supply and demand. Among these studies were five that performed rigorous reliability checks under extreme weather and demand conditions.
While solar and wind are variable, or “intermittent,” resources, grid operators have many options to ensure the flexibility and reliability of the grid. First, a high level of diverse, variable renewables can be balanced across the grid with adequate transmission capacity and energy storage to ensure reliability. The Biden administration’s “Investing in America” agenda, for example, has made and accelerated investments toward developing and deploying energy storage solutions and expanding grid transmission. Furthermore, there are many other clean energy resources that are “firm” and not variable; for example, geothermal, hydropower, and nuclear can provide dispatchable power to the grid. Overall, robust studies and modeling analyses have shown clearly that even with declining usage of fossil fuel generation, a clean electricity grid is capable of maintaining resource adequacy by pairing renewable energy with energy storage and other tools to ensure flexibility.
There is a robust field of study and evidence that renewable energy can maintain reliable resource adequacy to balance supply and demand of energy, as well as provide essential reliability services of the grid.
Resource adequacy, though, is only one important component of grid reliability. The grid must also be able to provide ancillary grid services, which refer to various functions that grid operators use to maintain operational reliability beyond sufficient energy generation. Some of these services include voltage control, frequency response, and ramping capabilities. Renewable energy sources are well-equipped to provide these ancillary services—sometimes even more effectively and efficiently than conventional fossil fuel generators.
For example, NREL, First Solar, and California ISO (CAISO) conducted a series of tests on a solar photovoltaic (PV) plant, assessing the capabilities of solar energy to provide these ancillary services. The study found that these solar projects with inverter controls were able to provide “services that range from spinning reserves, load following, voltage support, ramping, frequency response, variability smoothing and frequency regulation to power quality.” Moreover, the solar plant performed comparably to, or better than, conventional fossil fuel-fired power plants in all test categories and services.
The same has been found with wind resources: A parallel study conducted on a wind farm confirmed that, using smart inverter controls, wind power plants can “provide balancing or regulation up and down, voltage regulation control, active power control through ramping capability, and frequency response.” In fact, Xcel subsidiary Public Service Company of Colorado has been using wind resources for a decade to provide ancillary reliability services.
Simply put, there is a robust field of study and evidence that renewable energy can maintain reliable resource adequacy to balance supply and demand of energy, as well as provide essential reliability services of the grid.
America must deploy all tools in its toolbox to move to the clean, reliable grid of the future
There are many existing tools and technologies that should be deployed at scale to support grid reliability. Measures such as demand response, energy efficiency, battery storage, microgrids, virtual power plants, and more will all help balance and meet energy demand and maintain the reliability and resilience of the grid. Meanwhile, grid operators can install smart inverter technologies and advanced power controls to help support the provision of essential reliability services. These technologies are all available now. According to the CAISO-First Solar-NREL study noted above, “All hardware components enabling PV power plants to provide a full suite of grid-friendly controls are already in existence in many utility-scale PV plants. It is mainly a matter of activating these controls and/or implementing communications upgrades to fully enable these.”
Importantly, many necessary reforms are in the hands of the Federal Energy Regulatory Commission (FERC) and other grid operators to provide clean and reliable energy. For one, FERC must take steps to increase transmission build-out, as this is necessary to bring more clean energy to the grid, reduce grid congestion, and maintain resiliency. Interregional transmission is especially paramount to preventing electricity shortages and allowing energy to move between regions to where it’s needed most.
FERC and grid operators must enact meaningful reforms to enable a transition to a clean and reliable grid at the speed and scale needed to confront the climate and reliability crises.
The need for greater interregional transmission was clearly demonstrated by the failure of the Texas electricity grid during Winter Storm Uri, the winter freeze that caused fatal electricity outages throughout the state in February 2021. Texas operates its own electricity grid, the Electric Reliability Council of Texas (ERCOT), which is effectively isolated from the rest of the country. Interregional transmission between ERCOT and other regions of the country could have prevented outages by allowing the flow of electricity between neighboring regions. Other grid-operating regions such as Southwest Power Pool (SPP) and MISO fared much better during Winter Storm Uri, as they were able to import electricity from regions in the East that faced milder temperatures. This demonstrates the reliability benefits of increased transmission build-out across the country. FERC can heed this lesson and use its authority to increase interregional transmission, thus improving the resiliency and reliability of the grid.
FERC must also take ambitious steps to unlock and speed up interconnection queues. Right now, more than 2,000 gigawatts (GW) of clean energy resources are sitting in queues waiting to connect to the grid. This is 1.6 times the capacity of the current U.S. grid. Reducing these delays would help expedite the build-out and deployment of reliable, clean energy.
In addition to FERC, there are many changes in the hands of grid operators to enable this transition. Specifically, regional transmission organizations (RTOs) and independent system operators (ISOs) must reform their policies that create barriers to deploying clean energy solutions. For example, MISO explicitly prohibits renewable energy resources from providing essential reliability services, despite their ability to do so effectively. Grid operators must update market rules so that they reflect the capabilities of renewable energy resources and the reality of the evolving grid system.
The climate crisis is here, and its destabilizing effects are threatening the grid. Fossil fuel-fired power plants are failing the grid, and the United States cannot rely on conventional generation to maintain reliability. Renewable energy is capable of providing both resource adequacy and operational reliability; the tools and resources are available and waiting to be connected to the grid. Now, FERC and grid operators must enact meaningful reforms to enable a transition to a clean and reliable grid at the speed and scale needed to confront the climate and reliability crises.