While Texans drag through another punishing heat wave, people have nervously watched the state's power grid, hoping it will hold up as the triple-digit days wear on. Under the blazing sun, the state has produced significant amounts of electricity from solar panels to help avoid shortfalls.
The heat pushed demand to a new record — topping 81,000 megawatts on Tuesday — but the state's grid operator has only requested that residents lower their power use one day during the heat wave, when electricity from wind and power plants that use coal, nuclear or natural gas fell short of their past output.
Solar power provided nearly 20% of the Texas grid's power needs on Tuesday before demand reached a new high.
A so-called "heat dome" has settled over the state, meaning an area of high pressure sits above while the area bakes, Houston-based meteorologist Matt Lanza said. This means June hasn't been very windy.
The heat has been punishing. Local officials have opened cooling centers while people working outside struggle to avoid heat-related illness. A postal worker died in Dallas last week as the heat index reached 115 degrees, and a teenager died while hiking in Big Bend National Park on a day when the temperature hit 119 degrees, according to news reports.
Experts credit the state's diversity of energy sources for keeping the lights on. The significant increase in solar power generation in recent years has helped meet the growing demand for electricity in Texas, which operates its grid largely independently of the rest of the country.
Some 16,800 megawatts of solar power could be produced on the state grid as of the end of May, compared with 2,600 in 2019, according to data from the grid operator, the Electric Reliability Council of Texas.
"The solar we've added in the last year has been tremendously beneficial, and the solar we will continue to add will also be beneficial," said Michael Webber, an energy resources professor at the University of Texas at Austin. "Solar is such a boon for us, for grid reliability."
Aaron Zubaty, chief executive officer of clean energy investment company Eolian, said solar power correlates with Texas' hot, sunny days. But like any power source, solar has limits — it can't produce power 24 hours a day.
Conditions on the electric grid often grow tightest when people get home from work, crank up their air conditioners, turn on televisions, do laundry or cook — often as the sun sets and solar power production drops.
Batteries and natural gas plants help in those critical hours before the winds typically pick up and wind power increases.
"Across the system right now, every resource is using its different attributes and working together throughout each 24-hour period," Zubaty said in a statement, adding that "without this amount of added solar resources, the grid would be in dire straits during midday hours."
The ‘solar surge'
Experts predict Texas will add more large-scale solar power infrastructure in the coming years than any other state. A recent Solar Energy Industries Association and Wood Mackenzie report forecasts that Texas will install enough infrastructure to produce nearly twice as much new solar power as California between 2024 and 2028.
This growth could catapult Texas closer to challenging California's rank as the nation's top solar producer. Texas is currently second.
Solar farms provide cheap, emissions-free power, said Doug Lewin, an Austin-based energy consultant. Fossil fuel-powered electricity generators generally offer their power for higher prices in part because they have to pay for their fuel. They also release greenhouse gasses that are driving climate change, which is raising global temperatures.
Solar development has thrived in Texas because of a variety of factors, said Susan Sloan, head of government affairs and market strategy onshore for clean energy company Ørsted, which completed a solar farm in West Texas and is building three more in the state.
Landowners wanted to lease property to solar companies and communities agreed to tax breaks. The state planned for building critical transmission lines to move power from sunny, windy West Texas to other parts of the state. Meanwhile, energy demand has grown with the population.
"It's just a big deal that the solar surge has continued, and that Texas is and has become such a powerhouse in solar," Sloan said.
Hardly any solar power flowed on the Texas grid 10 years ago, when wind energy had already begun its steady rise. Natural gas has held steady over the past decade, providing about 50% of the state's power needs, while renewable power has become an increasing percentage of the state's overall power generation and coal-powered plants have closed.
In 2022, wind and solar power met around 30% of the state grid's electricity needs.
The state's electricity market has made it relatively easy for renewable energy companies to get the necessary permits and connect to the grid, said Rob Minter, senior vice president of government and regulatory affairs for ENGIE North America. ENGIE has 1,700 megawatts of solar power operating or under construction in Texas.
"It's frankly superior to most of the market designs that we see across the rest of the country," Minter said.
Lawmakers passed laws to help natural gas power
The legislative session that ended last month focused on changing this power mix. Lawmakers worried about the trend toward more wind and solar power, characterizing renewables as unreliable because they cannot generate power 24/7.
Keeping enough natural gas-fueled power on the system remains important because those plants — which can provide electricity on demand because they don't rely on wind or sun — help smooth out minute-by-minute fluctuations on the grid as power supply and demand ebb and flow, said Mike Greene, a former chair of ERCOT. Batteries can do this too, though they can't run for as long.
Politicians focused on boosting natural-gas-fueled power. They threatened to impose strict regulation on renewable energy projects, decided no longer to allow solar or wind projects to qualify for school tax breaks and established new ways to support natural-gas-fueled power financially.
Mona Tierney-Lloyd, head of U.S. state public policy at Enel North America, said lawmakers' intent to create a less-inviting environment for renewable energy was clear. Enel, a clean energy company, has more than 3,500 megawatts of large-scale solar power operating or under construction within the Texas grid.
"There's no mistaking the tenor of this legislative session, which clearly intended to support new ... fossil [fuel power] generation and to, I would say, create some headwinds for new renewable development in the state," Tierney-Lloyd said.
The ramifications of their decisions on power development remain to be seen.
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This article originally appeared in The Texas Tribune at https://www.texastribune.org/2023/06/28/texas-solar-power-grid-heat-wave/. The Texas Tribune is a member-supported, nonpartisan newsroom informing and engaging Texans on state politics and policy. Learn more at texastribune.org.