This week's roundup of Houston innovators includes Remington Tonar of Cart.com, Joey Sanchez of The Ion, and P.J. Popovic of Rhythm. Courtesy photos

Editor's note: In this week's roundup of Houston innovators to know, I'm introducing you to three local innovators across industries — from e-commerce to energy — recently making headlines in Houston innovation.

Remington Tonar, chief commercial officer of Cart.com

With $150M in VC raise, this Houston company is re-envisioning the future of e-commerce operationsRemington Tonar of Cart.com joins the Houston Innovators Podcast this week. Photo via Cart.com

In a world where Amazon dominated the e-commerce world, Cart.com is offering merchants but an alternative and a supplemental tool.

As Remington Tonar, chief commercial officer of Cart.com, explains on the most recent episode of the Houston Innovators Podcast, Cart.com connects the dots for e-commerce companies, and, in fact, works alongside Amazon, too. While Cart.com clients can use the suite of software services to create their own shop, ship out of Cart.com's distribution centers, etc., they can also list their products on Amazon too.

"I like to view Amazon as co-op-etition. We can coexist with Amazon," Tonar says on the show. "We're not antithetical to Amazon. We're not mutually exclusive. We can work with folks who are selling on Amazon to build their direct-to-consumer business, and we are doing that today." Click here to read more and stream the episode.

Joey Sanchez, senior director of ecosystems at The Ion

Joey Sanchez is now the senior director of ecosystems at The Ion. Photo via HX.com

Joey Sanchez, who's worked in corporate partnerships for Houston Exponential for a few years, has hopped over and into a new role at The Ion.

In his new role, he will work with the Houston early-stage investing and startup community, including founders, early-stage startups, scaled startups, early-stage angel investors, venture capital investors, and corporate partners, to grow the Ion's presence in Houston.

"Houston and Texas are seeing unprecedented growth in tech and innovation. I am excited for the opportunity to continue building and supporting the Houston innovation ecosystem," says Sanchez the release. "An ecosystem needs harmony among all aspects involved, and I have always enjoyed connecting people. The overarching goal remains to build a vibrant ecosystem that supports a high frequency of connections between critical stakeholders to realize outsized success." Click here to read more.

​P.J. Popovic, CEO of Houston-based Rhythm

P.J. Popovic, CEO of Houston-based Rhythm, explains Renewable Energy Certificates work and their impact on Texas. Photo courtesy of Rhythm

What are RECs and what difference do they make? P.J. Popovic, CEO of Houston-based Rhythm, shares his expertise on Renewable Energy Certificates in a guest column for InnovationMap.

"Through PPAs, various risks, credit needs, and long-term commitments create challenges for many organizations to meet their sustainability goals. So, while RECs do not provide as material of a market signal as PPAs, with the recent changes in market prices, RECs can now be considered a meaningful, profitable market signal for renewable projects." Click here to read the article.

P.J. Popovic, CEO of Houston-based Rhythm, explains Renewable Energy Certificates work and their impact on Texas. Photo courtesy of Rhythm

Houston expert: Why higher REC prices are good for the future of renewables

guest column

We all know what renewable energy is — wind, solar, biomass, geothermal, hydropower — but how do you purchase it? It's invisible. Not to mention when energy from any source enters the electricity grid, there's no way to track all those electrons.

Renewable Energy Certificates have made it possible

Renewable Energy Certificates, or RECs, allow us to track your clean energy. Each individual REC represents one megawatt-hour of clean energy generated. And while a REC isn't technically electricity, it represents the clean energy going into the electricity grid—meaning homes and businesses claim their commitment to renewable energy if their electricity is supported by RECs.

It's also important to understand what a renewable energy certificate is not: an offset. An offset represents a metric ton of emissions avoided and a REC represents 1 MWh of clean energy generated. While each have similar goals, they are not quite the same thing.

Not all RECs are created equally

The market for RECs is fluid. Due to the growth of the renewable energy market, RECs have been oversupplied for years. This has created low prices and little-to-no financial advantage for the facilities that generate clean electricity (e.g., wind facilities, solar farms, hydro plants).

In Texas, the retail electricity market is inundated with renewable electricity claims said to be supported by RECs. The energy plan you sign up for might come from solar, wind, biomass, or even trash incineration, but the renewable energy facilities likely are coming from outside Texas, located in places like California, Canada, or elsewhere. While there's no wrong way to switch to renewable energy, supporting renewable energy sources inside Texas helps Texans move closer to being a more sustainable state.

Choosing Texas renewable energy plans and your actions do have a true, real-world impact more than ever before

Some critics have argued that REC-supported renewable energy plans don't meet the highest standard of sustainability arguing RECs are not foundational to the existence of renewable energy assets. In other words, they argue that RECs don't provide a material revenue source for renewable projects because they don't incentivize new developments of renewable facilities to be built.

When RECs were trading for less than a dollar, this was a valid argument. But that was then, and this is now.

In the last year alone, voluntary renewable energy certificate prices have skyrocketed and are now between $7 and $10 per MWh. This means RECs can now contribute up to 30 percent of a renewable facility's revenue. Naturally, this encourages more and more clean-energy facilities and clean-energy jobs to be created. A win-win.

What about Power Purchase Agreements?

A Power Purchase Agreement, or PPA, is a tad different than a REC. In a PPA, the developer of a renewable project (solar arrays at a solar farm, or turbines at a wind farm) can sell the actual energy it produces over a 10-to-20-year contract.

While the sale of this renewable energy still contributes to a larger portion of project revenues, the revenue mix has clearly shifted, and RECs cannot be considered an immaterial incentive anymore. Sure, PPAs are a stronger market signal for renewable project development, but only a couple of hundred organizations globally utilize PPAs. This makes them very challenging for businesses to access.

Through PPAs, various risks, credit needs, and long-term commitments create challenges for many organizations to meet their sustainability goals. So, while RECs do not provide as material of a market signal as PPAs, with the recent changes in market prices, RECs can now be considered a meaningful, profitable market signal for renewable projects.

Making the future of renewable energy in Texas even brighter.

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P.J. Popovic is the CEO of Houston-based Rhythm.

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Houston brain health co. secures $6.5M for rare disease study

neuro funding

Houston-based Goldenrod Therapeutics, part of Fannin Partners' portfolio, has announced the initial close of a $6.5 million series seed preferred stock round.

The round was led by Ataxia Ventures and an affiliate of Fannin, according to a news release.

Goldenrod Therapeutics plans to use the funding to support manufacturing, formulation optimization, IND-enabling studies and a Phase I study of its drug to treat brain inflammation, known as 11h.

The study will consider how 11h, which blocks the enzyme PDE4, could treat Friedreich’s ataxia (FA), a rare genetic disease that affects movement, speech and balance. To date, other PDE4 inhibitors have proven to regulate neuroinflammation and neuronal signaling, but have had adverse gastrointestinal side effects or have not reached enough of the central nervous system, according to Goldenrod.

The company says its 11h is expected to have "broad applicability" with limited emetric side effects.

“Our 11h program is a next-generation, orally bioavailable, brain-penetrant PDE4 inhibitor, where researchers overcame longstanding limitations associated with earlier PDE4 inhibitors," Dr. Dev Chatterjee, CEO of Goldenrod, said in the news release. "We believe this creates the potential for a best-in-class therapy for Friedreich’s Ataxia and a potential foundation for development across multiple neurodegenerative and neuroinflammatory disorders.”

11h was first developed at the University of Nebraska Medical Center (UNeMed). Houston-based Fannin Partners in-licensed the product 2020 and landed SBIR Phase I funding to support its initial development for opioid use disorder soon after.

Goldenrod has also received funding to study 11h's effectiveness for multiple sclerosis, methamphetamine addiction and cocaine addiction.

Goldenrod says it is developing 11h to target a variety of neurological and inflammatory conditions, including Alzheimer's disease, multiple sclerosis, ALS, substance use disorders, Batten disease, pain and traumatic brain injury.

27 Houston companies make Fortune 500 for 2026, led by energy giants

Houston HQs

Editor's note: This article has been updated to correct the number of companies based in the Dallas-Fort Worth area.

Houston is a giant among U.S. hubs for corporate headquarters.

The 2026 Fortune 500 lists 27 companies based in the Houston area, with many energy companies claiming top spots. Houston ties with Chicago for the second-most Fortune 500 headquarters, preceded only by New York City (53). Dallas-Fort Worth is home to 24 Fortune 500 headquarters.

Texas leads the nation for Fortune 500 headquarters (57), with California in the No. 2 spot and New York at No. 3.

“Texas is the undisputed headquarters of headquarters,” Gov. Greg Abbott said in a news release. “The world’s leading businesses invest with confidence in Texas because of our welcoming business climate, predictable regulatory environment, and skilled and growing workforce. People and businesses are choosing Texas because Texas works.”

The 2026 Fortune 500 ranks the largest U.S. corporations based on revenue in fiscal year 2025.

Here’s a rundown of the 27 Fortune 500 companies based in the Houston area.

  • No. 9 ExxonMobil
  • No. 21 Chevron
  • No. 29 Phillips 66
  • No.55 Sysco
  • No. 75 ConocoPhillips
  • No. 89 Enterprise Products Partners
  • No. 103 Plains GP Holdings
  • No. 133 Hewlett Packard Enterprise
  • No. 149 NRG Energy
  • No. 157 Quanta Services
  • No. 164 Baker Hughes
  • No. 173 Occidental Petroleum
  • No. 179 Waste Management
  • No. 201 EOG Resources
  • No. 204 Group 1 Automotive
  • No. 207 Halliburton
  • No. 223 Cheniere Energy
  • No. 236 Corebridge Financial
  • No. 262 Targa Resources
  • No. 266 Kinder Morgan
  • No. 388 Westlake
  • No. 435 CenterPoint Energy
  • No. 438 APA
  • No. 440 Comfort Systems USA
  • No. 455 NOV
  • No. 488 KBR
  • No. 496 Coterra Energy. Oklahoma City, Oklahoma-based Devon Energy and Houston-based Coterra Energy merged in early May, with the combined company retaining the Devon Energy name and the Houston headquarters.

The Greater Houston Partnership notes the Houston area soon will welcome its 28th Fortune 500 company. Expand Energy (formerly Chesapeake Energy), appearing at No. 362 on the 2026 list, says it’s moving its headquarters from Oklahoma City to Spring this year.

As the natural gas producer prepares to relocate to Texas, it’s hunting for a new leader. Nick Dell’Osso stepped down as president and CEO earlier this year. Board Chairman Michael Wichterich is interim president and CEO.

Dell’Osso became president and CEO of Oklahoma City-based Gulfport Energy effective May 28.

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This article first appeared on EnergyCapitalHTX.com.

Elon Musk's SpaceX is about to make its debut on Wall Street

Money Moves

Elon Musk's rocket company SpaceX will make its debut on Wall Street Friday, June 12, and both institutional and retail investors are expected to gobble up the 555.6 million shares going up for sale at $135 apiece. Musk, already the world's richest man, could become its first trillionaire.

SpaceX is likely to become the biggest IPO ever, with proceeds of around $75 billion. SpaceX hopes to become the first company to send people to Mars. In fact, part of Musk’s future compensation depends on SpaceX eventually establishing a colony of at least 1 million people on the red planet.

Why SpaceX is going public now

In a video conference on Musk's social media platform X, he told JPMorgan CEO Jamie Dimon that people have suggested for the last 10 years that he take SpaceX public. He's doing it now because the company plans to put 100,000 next-generation Starlink satellites into orbit. Deploying AI data centers in space is a “massive new growth base and you need capital for that,” he said.

Going public provides access to the capital that SpaceX needs. But it also exposes it to more scrutiny from shareholders and more regulatory oversight. That includes filing quarterly financial reports, which critics say incentivizes short-term thinking over longer-term planning and creates unnecessary costs for a company. Securities regulators are currently soliciting public comment on a proposal to require public companies to file the financial reports only twice every year.

How the IPO impacts the company

Musk will hold the majority of a special class of shares, giving him control over decisions related to company strategy, finances and personnel. On the latter, because of his ownership of most of these Class B shares, the only person who can fire Musk as CEO is Musk.

The company credits Musk with being the “driving force” behind its growth, innovation and success. But what happens if Musk is no longer in the picture? SpaceX warns that the loss of Musk could disrupt its ability to execute its strategy as well as hurt its “reputation and relationships with customers, partners and other stakeholders.”

The company also warns that finding a replacement with the same skills and experience as Musk would be time-consuming, if not nearly impossible. As Wedbush Securities analyst Dan Ives wrote Wednesday, “At the end of the day Musk is SpaceX and SpaceX is Musk.”

What could make or break SpaceX

Currently in the test phase, the gigantic reusable Starship rocket is key to SpaceX realizing Musk's ambitions. Much of the commercial space business hinges on SpaceX developing Starship’s capability to be fully reusable and hearty enough for a quick turnaround between flights. If that doesn't happen, SpaceX warns that putting data centers and satellites in space will take longer and cost more money, meaning it risks customers bailing on the company.

Analysts say that by pioneering reusable rockets, SpaceX has established a clear lead on competitors such as Blue Origin, led by Amazon founder Jeff Bezos. The Starlink satellite business competes with, among others, AST SpaceMobile – which is relying on a SpaceX rocket to send its latest generation of satellites into orbit next week.

The prospectus filed last week says SpaceX’s biggest potential market is the sale of business-oriented artificial intelligence products designed to transform how people get work done. It’s an opportunity SpaceX predicts would be worth $22.7 trillion if it could somehow dominate rivals like Anthropic, OpenAI and Microsoft in a highly competitive industry. But the prospectus shows no clear path to profitability for the xAI business, which merged with SpaceX earlier this year.

Why Wall Street is paying attention

If the SpaceX IPO is as successful, the stock could quickly join the Nasdaq 100, a widely followed index that tracks the 100 largest non-financial companies in the composite. That's important because some popular funds, such as the $460 billion QQQ exchange-traded fund, mimic the index and will automatically buy whatever is listed in the index.

Nasdaq recently changed its rules to allow select companies to enter the Nasdaq 100 after just 15 trading days.

S&P Dow Jones Indices, on the other hand, is sticking to established and more traditional thresholds that will not allow SpaceX or other companies with gargantuan IPOs faster entry into its S&P 500 index. That means even high-profile companies will still need to wait for their stocks to trade a full 12 months before they can enter the index.

Companies want to be in the S&P 500 in particular because it's arguably the most important index on Wall Street, with trillions of dollars either mimicking it exactly or benchmarked against it. Vanguard's VOO fund that tracks the S&P 500 has roughly $950 billion invested in it, for example.