The two-lane highways of the electric grid in deep South Texas were simply not built for four-lane expressway traffic, now required to keep pace with power demand to reduce power outages inside the AEP Texas network.

Congestion on these electrical highways and severe weather along the coast that knocks out the lines contribute to potential power outages or variations of electricity throttling to protect the grid during a demand spike. 

However, a massive shift is underway for these super-powered highways, which enable electricity to flow from one side of the state to another and even cross international borders. 

In the coming months, this change will be led by a few general contractors of the electric highways, including American Electric Power, in collaboration with other major industry players. 

“We’ve experienced, in the past three years, the amount of growth that typically, if you were to take a look at our statistics, would take 30 years to achieve,” Omar Lopez, director of communications for AEP Texas, said in an interview with the Rio Grande Valley Business Journal. 

More people need electricity in Texas

AEP Texas is an electric transmission company with a base in Corpus Christi and is a subsidiary of the Columbus, Ohio-based utility corporation. AEP Texas serves 1.1 million customers, many of whom live in the Rio Grande Valley, but its service area also includes swaths of South, West, and East Texas. 

For example, electricity demand across its footprint grew by 50 megawatts between 2011 and 2021. Demand grew by 550 megawatts between 2022 and 2023, according to the company. During 2024 alone, demand for electricity by AEP Texas customers increased by 600 megawatts. 

But not all ratepayers may understand that they are paying for AEP Texas’ transmission line improvements in their monthly bills because the company does not send invoices directly to customers, officials explained. Nor does it generate any electricity from natural gas, wind, or solar for purchase. 

“We don’t sell it, we don’t make it, we just move it,” Lopez said. 

That means the $1 billion investment to improve electric reliability for the Rio Grande Valley, which began in 2014 and wrapped up in 2016, known as the Cross Valley Transmission Project, was ultimately paid for by customers of AEP Texas. 

More than a decade ago, the Texas Public Utility Commission granted permission to operators to invest billions into the grid. The Cross Valley Transmission Line was a joint venture between AEP Texas and Warren Buffett’s Berkshire Hathaway Energy Company in collaboration with Dallas-based Sharyland Utilities, as Electric Transmission Texas, or ETT.

Texas mandates a better electric grid 

Now there’s a new electricity transmission line and substation plan approved by state regulators, prompted after the grid froze and so did its customers in 2021. 

That was during the ‘Great Texas Freeze’ in February 2021, which revealed deficits in the state’s power grid. At least 246 people across Texas died during that winter storm, officials estimated. 

Texas is unique in that its grid is overseen by the Electric Reliability Council of Texas, or ERCOT, and the regulator of AEP Texas is the Texas Public Utility Commission. The utility commission began requiring electric transmission companies to improve infrastructure after the major statewide freeze and subsequent grid failures.

“They mandated that we come up with a plan to bring more transmission to the Valley,” Lopez said. 

The improvements are typically adding more transmission lines to build redundancy and more substations to have more options when controlling the flow of electricity, improving reliability, and reducing power outages.

By 2026, there’ll be even more electricity transmission line work completed across the Rio Grande Valley to improve the grid. 

For now, outages and electric reliability are still such an issue in South Texas despite previous investments, in part because there’s a lack of electricity generation, and the existing lines are on the smaller side, from 161 kilovolts to 345 kilovolts, but still high-voltage lines.

“There are capacity issues because there is only so much generation in Texas; our job is to move what’s available,” Lopez said. “Whenever you think about new homes, new families, new factories, new developments, that all takes electricity, so we’re moving as much as we can, but there’s only so much in Texas [generated] to move around.” 

Electrical outages are often caused by trees or other vegetation falling on power lines and disrupting the circulation of electricity, which requires manual removal and debris clearing in the company’s right-of-way, Lopez said. 

“AEP Texas has the most coastal exposure of any utility in Texas, [which] includes the Rio Grande Valley. So when a storm hits the Texas coast, we don’t consider McAllen out of the woods at all. Everything from Port Isabel and South Padre Island, we know all of that is vulnerable to a hurricane’s storm surge or aftermath,” he said. 

Highest-voltage transmission lines 

In April 2025, the Public Utility Commission approved transmission companies to build three 765 kilovolt lines in Texas. 

“Those are the largest lines really in the country right now. We don’t have any here in Texas yet,” Lopez said. 

The first stretch will be a collaboration between municipally-owned utility CPS Energy in San Antonio and AEP Texas in Corpus Christi. 

“It’s huge for our region. At the very least, the 765 kilovolt line is going to be able to absorb as much generation as [the power generators] can give us,” Lopez said. “That’s a good thing because it’s going to move that electricity all the way from the Permian Basin to San Antonio and everything along that route. It’s going to change the way the state can approach economic development.” 

But in the Rio Grande Valley, there will be new 345-kilovolt lines under construction soon. 

“This is going to bring a lot more reliable electricity to the area,” Lopez said. 

Much of AEP and ETT’s investments are in the pre-construction phase, with plans to add 190 miles of 345 kilovolt transmission lines and two substations to the grid by the end of 2026. 

South Texas Electric Transmission Projects

“So what’s happening is we’re talking to landowners as we’re securing right-of-ways,” Lopez said, “But then when the construction starts, it’s all hands on deck. We’ll have a lot of resources in the Valley building these lines.”

The physical structure of the Texas electric grid includes power generation, electric substations, high-voltage transmission lines, and residential transmission poles in neighborhoods. 

For example, there’s a natural-gas-fired power plant known as Calpine Hidalgo Energy Center in Edinburg. Natural gas is used to generate steam, which then produces electricity that is connected to an electrical substation and then travels through transmission lines to the end customer. 

Not in my McAllen backyard 

But that doesn’t mean the upgrades to the grid transition will happen without friction. 

The city of McAllen has already voted down a zoning variance for a project that was at least two years in development for a new AEP electric substation after neighborhood pushback by Meadow Ridge homeowners.

There are eight substations across McAllen. The substation near Meadow Ridge was supposed to alleviate electric outages in North McAllen. 

AEP Texas purchased a nearly 5-acre property behind Zamora’s Tire Shop near the intersection of Buddy Owens Boulevard and North Bentsen Road in McAllen in 2023.

For now, AEP Texas is back to scouting around for available real estate, including two more proposed substations in South McAllen, which could be a similar fight through zoning to get permission to build. 

“It’s challenging because people love where they live. [But] the reality is that lines are getting bigger, the demand for electricity grows every single day, so it’s going to require more infrastructure and more facilities,” Lopez said. “We need to have the facilities and equipment to deliver that electricity.”