The Tennessee Valley Authority has led the South in carbon reduction since 2015, but a new study suggests the utility's growing reliance on natural gas to produce more electricity will prevent TVA from achieving its carbon-free target by 2050 and is far behind President Biden's goal of moving the electricity industry to zero-carbon emissions by 2035.
In its fifth annual review of decarbonization programs by utilities in the South, the Southern Alliance for Clean Energy said TVA has the largest planned addition of new natural gas generation of any U.S. utility. The new gas plants and projected growth in power demand in the Tennessee Valley are projected to limit future decarbonization after the utility's industry-leading 60% drop in carbon output from 2010 to 2021.
"In one of the most dramatic shifts from steep decarbonization to slow decarbonization, TVA's current trajectory means it is unlikely to decarbonize by 2050, let alone 2035," Heather Pohnan, the energy policy manager for the Southern Alliance for Clean Energy, said in an assessment of southern utilities released Wednesday. "TVA's reliance on fossil fuels is expected to remain unchanged between now and 2030 despite several large coal retirements, as TVA replaces coal nearly 1-for-1 with gas."
TVA plans to phase out the last of the 59 coal-fired plants it once operated by 2035 as the federal utility moves to cleaner energy sources to replace the coal that once supplied a majority of TVA's power.
In an earnings call last week, TVA President Jeff Lyash said TVA is moving as quickly as it practically can toward a zero-carbon generation mix. But Lyash said delays in getting enough solar panels are limiting the growth of solar power, and TVA needs natural gas generators to meet power demand peaks when the sun doesn't shine and the wind doesn't blow.
"TVA is building as much solar as we can," Lyash said."We're limited by panel availability, but we're hopeful that the supply chain will free up and we'll soon be able to act on what is the nation's largest clean-energy RFP (request for proposals). We're will on our way toward building 10,000 megawatts of solar."
In May, TVA announced it is actively evaluating 40 projects totaling about 6,000 MW of solar and storage capacity, which could potentially double the amount of TVA's solar power.
New natural gas plants are 60% cleaner and emit far less carbon than the coal plants they replace and are needed as part of a balanced portfolio to meet what TVA projects will be a doubling of electricity use by 2050 in the Tennessee Valley as electric cars replace gas-powered vehicles and more industry is electrified, Lyash said.
"We're building the kind of gas assets that are flexible and can ramp up quickly when other generation is not running," Lyash said. "We think this balanced solution is what our customers want. They want reliable and affordable energy even as we reduce carbon, and that's what we're going to continue to do."
In the first nine months of its current fiscal year, TVA got nearly 60% of its energy from carbon-free sources. Between 2016 and 2020, Tennessee reduced the carbon footprint of its power generation more than any other state, according to a September analysis by the U.S. Energy Information Administration.
But in a webinar Wednesday discussing utility decarbonization programs, Southern Alliance for Clean Energy President Stephen Smith said the global climate crisis demands TVA and other utilities do more immediately to limit their emissions of greenhouse gases that contribute to global warming.
"Decarbonization is an absolute driver of what is needed to save our planet," Smith said. "What we are seeing this summer has got to be a wake-up call to all of the decision-makers that we've got to get more serious about what is unfolding with this parade of horribles from forest fires, air quality problems, unprecedented heat waves and widespread flooding. These are real and present dangers, and we have to be making decarbonization more of a priority."
TVA is launching a new long-term power planning process this summer, known as an integrated resource plan, to outline its energy options for the next couple of decades. The Southern Alliance for Clean Energy removed TVA from its "solar blocker" label given to the federal utility in the past after TVA moved to more than triple its solar generation. But TVA has been slower than most of its utility neighbors to buy or build more solar generation, Smith said.
TVA is adding more generating from natural gas "because it is the only mature technology that allows us to quickly add a tremendous amount of renewable energy" to balance more volatile solar and wind generation, TVA spokesman Scott Fiedler said.
"Natural gas is critical because it is dispatchable, providing reliability when the sun does not shine and the wind does not blow," he said in an emailed statement.
The TVA board has also allocated $200 million to study the building of new small modular reactors to generate carbon-free electricity from factory-built nuclear power plants. TVA already gets more than 40% of its electricity from its seven existing nuclear reactors.
But Smith doesn't think new nuclear power will be a significant contributor to carbon reductions in the South because such units haven't yet proven to be built in a timely or cost effective manner, he said.
"They can't build new nuclear plants on budget or on schedule, so the price points are constantly missed," Smith said. "Every time you are spending billions of dollars chasing after fairy dust (with new nuclear designs), you are not spending that money in real tangible solutions on the ground that can offset these carbon emissions."