San Antonio to End Use of Coal Within Five Years
But CPS Energy’s decision to switch to natural gas highlights the potential and peril of cities’ clean energy transition.
In 2010, coal use in the United States was already dropping precipitously in favor of cheaper and more environmentally friendly options, including natural gas and renewables. That year, San Antonio’s electric utility made the anachronistic decision to add a new coal-fired generator to its J. K. Spruce power plant. But soon after, the facility struggled financially to compete with fracked gas, solar, and wind energy. Community members were against heavy pollution generated by burning coal. Clearly, Spruce’s days were numbered.
This week, board members of CPS Energy voted to stop using coal at the power plant, which includes a unit from 1992 as well as the 2010 addition, within five years.
“San Antonio is ending the use of coal,” Mayor Ron Nirenberg, a member of the board, announced.
Although the board’s vote on Monday directly affects just one metro area, San Antonio’s attempts to reduce greenhouse gasses indirectly affect the whole planet. CPS Energy is the country’s largest municipally-owned electric utility. Mayor Nirenberg tries to position San Antonio as a climate leader, and he has a national platform through membership in groups like the EPA’s Local Government Advisory Committee and the Bloomberg-funded American Cities Climate Challenge. So safe to say, other cities and utilities are watching.
But this decision only closed one long chapter of advocacy and debate and opened another. Board members elected to retrofit Spruce’s newer unit to run on gas, as part of an overall plan to diversify the utility’s energy mix.
Most of the dozens of officials, residents, business representatives, and activists at the meeting celebrated the move. “This victory has been a long time coming,” said Emma Pabst, a campaigner with the Sierra Club’s Lone Star Chapter. But she and others criticized the move toward gas as shortsighted. “It’s just not the bold action we need to see on climate.”
CPS Energy’s commitment to forgo coal exemplifies how cities and utilities can help address the climate crisis by burning fewer fossil fuels, of which coal is arguably the dirtiest. But the decision to rely on gas instead highlights the trade-offs communities are making to deal with the already-apparent consequences of climate change.
San Antonio isn’t alone in seeking to break up with coal. Austin is currently struggling to divest from co-ownership of a coal plant in La Grange. In 2020, Brownsville left a contract with a coal plant on the Texas-Oklahoma border in favor of solar and wind. Before that, the cities of Bryan, Denton, Garland, and Greenville shut down a coal plant they jointly owned, also in favor of solar power.
But San Antonio’s Spruce coal power plant is one of the youngest in the United States and could have kept running into the 2060s. CPS’ new plan to close the older half by the end of 2028 and convert the newer half to gas by the end of 2027 will significantly slash the city’s greenhouse gas emissions and reduce toxic pollution in the local air and water too.
Another reason to watch San Antonio is its vulnerability to heat. In 2022, local temperatures rose above 100 degrees Fahrenheit on more than 50 days, the city’s hottest summer on record. Along with the temperature, air conditioning use and demand for electricity rose to all-time highs. Supplying enough power—at a rate people can afford—during heat waves and other extreme weather is a priority for residents and officials alike amid lingering trauma and financial fallout from 2021’s Winter Storm Uri.
Leading up to its decision to drop coal, CPS considered nine “portfolios” of energy that included different mixes of coal, gas, and renewables. The board members ultimately decided to aim for zero coal, but more gas (as well as more solar, wind, and battery storage), in the name of reliability and affordability.
“People just want to know about reliability,” said board member Francine Sanders Romero, who’s also a professor of public administration at the University of Texas at San Antonio. She framed keeping gas in the mix as an ethically fraught but ultimately necessary choice to adapt the city to increasingly extreme weather.
Officials, though, are using “reliability” as shorthand for a more complicated concept.
Gas is not always more reliable than renewable energy: During Uri, many parts of the gas supply chain failed and contributed to widespread power outages, as well as to eye-wateringly high energy prices. CPS staff and board members are determined to ensure the utility has enough of its own power supply to avoid buying additional electricity from ERCOT, the state’s grid operator. “I would prefer us to be less reliant, less exposed to the volatility of the state grid,” Nirenberg said.
Even partially closing the plant “means so much for the quality of the air we breathe,” said DeeDee Belmares, a climate justice organizer with Public Citizen and a member of CPS Energy’s Rate Advisory Council—a group of community members appointed to advise the utility on generation planning and rates.
The energy portfolio CPS has settled on will put San Antonio on track to meet its near-term climate goal of reducing the city’s greenhouse gas emissions 41 percent by 2030. But continuing to burn gas long-term would put the city’s end goal of reaching zero greenhouse gas emissions by 2050 out of reach. The world’s preeminent climate scientists have calculated this timeline on behalf of the United Nations as necessary to limit global warming to 1.5 degrees Celsius or 2.7 degrees Fahrenheit—what a quorum of the world’s countries decided would be a still-bad but somewhat manageable level of climate crisis.
“We still need a carbon-free future,” Belmares said.
Local officials, however, don’t yet know how to get there from here.
Around the country, many utilities review their generation mix every three to five years as a best practice, said Belmares. She and other advocates who spoke at Monday’s meeting, as well as Nirenberg himself, asked CPS to revisit its plan every few years. Some hope that new technologies—like cheaper battery storage for renewable energy, hydrogen as an alternative to methane gas, and offshore wind energy in the Gulf of Mexico—may soon become viable options.
“For now, what we need is a well-balanced portfolio,” said Jeff Webster, a former city council member who now leads the public policy committee at the San Antonio Chamber of Commerce, which pushed for the winning portfolio. But, Webster added, “If you lock into something and aren’t smart enough to change when technology improves, then shame on you.”
Board Chair Willis Mackey promised the conversation will continue. “We evaluate this process every two-three years,” he said.
CEO Rudy Garza said he intended to update the board annually, as state and federal regulations change.
ERCOT must now approve CPS’ proposed timeline for closing and converting the Spruce plant based on the plan’s impact on statewide grid reliability. It’s possible the grid operator may require the plant to stay open past 2028, Garza said, but he did not seem worried about ERCOT rejecting the plan outright. New gas and renewable power should more than make up for what’s lost from Spruce.
San Antonio is, however, swimming against the greater Texas current. Earlier this month, the Public Utility Commission proposed a redesign of the state’s electricity market that would incentivize existing power plants to stay open, and that experts say could hurt new renewable projects. Within this state context, local initiatives like San Antonio’s may become even more important in driving Texas’ transition from fossil fuels to clean energy.