A team of Rice University researchers has found a way to convert data center waste into clean power using rooftop solar collectors. Photo courtesy Rice University.

As data centers expand, their energy demands rise as well. Researchers at Rice University have discovered a way to capture low-temperature waste heat from data centers and convert it back into usable power.

The team has introduced a novel solar thermal-boosted organic Rankine cycle (ORC)—a power system that uses a safe working fluid to make electricity from heat. The design incorporates low-cost rooftop flat-plate solar collectors, which warm the data center’s coolant stream before it enters the ORC. The findings, published in Solar Energy, show that the additional “solar bump” helps surpass the technical roadblocks with data center waste, which has typically been too cool to generate power on its own.

The research was supported by the Alliance for Sustainable Energy LLC, the National Renewable Energy Laboratory and the U.S. Department of Energy.

“There’s an invisible river of warm air flowing out of data centers,” Laura Schaefer, the Burton J. and Ann M. McMurtry Chair of Mechanical Engineering at Rice and co-author of the paper, said in a news release. “Our question was: Can we nudge that heat to a slightly higher temperature with sunlight and convert a lot more of it into electricity? The answer is yes, and it’s economically compelling.”

Traditionally, electric heat pumps have been used to raise temperatures before recovery, but the benefits were limited because the pumps consumed significant extra power.

Kashif Liaqat, a graduate student in mechanical engineering at Rice, and Schaefer achieved a "temperature lift” by using solar energy to create thermoeconomic models. They modeled affordable, low-profile rooftop solar collectors that fed into an ORC and tied into a liquid-cooling loop. The collectors were validated against industry tools and tested at some of America’s largest data center hubs in Ashburn, Virginia, and Los Angeles, which provided varying climate challenges.

The system recovered 60 percent to 80 percent more electricity annually from the same waste heat, with a 60 percent boost in Ashburn and an 80 percent boost in Los Angeles, according to Rice. It also achieved over 8 percent higher ORC efficiency during peak hours, and an increase in annual average efficiency. The approach also lowered the cost of electricity from the recovered power by 5.5 percent in Ashburn and by 16.5 percent in Los Angeles.

“What the industry considers a weakness becomes a strength once you add solar,” Liaqat said in a news release. “That’s great news for modern data centers.”

Next up, the team will look to pilot its hybrid system in operational sites and explore thermal storage, which the researchers hope could bank solar heat during the day to assist with energy recovery efforts at night.

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Houston energy expert discusses why hydrogen still has a future

Guets Column

Not long ago, hydrogen was hailed as the next big thing in clean energy. Investors poured in, and countries from Japan to Germany built ambitious hydrogen strategies. It wasn’t a new discovery; hydrogen has been used for over a century in refineries and fertilizers, but it suddenly found itself reborn as the world began working toward decarbonization.

When hydrogen burns, the only byproduct is water. Green hydrogen, produced with renewable power, could replace fossil fuels in everything from trucks to ships to steel mills. But the momentum has cooled. Costs remain stubbornly high, several projects have been delayed or canceled, and policy support has wavered. In the U.S., a change in administration has created uncertainty. In Europe, some governments are slowing funding or revising hydrogen mandates. Even the International Maritime Organization (IMO) recently postponed a key vote on fuel-carbon standards.

Yet as Mike Graff , former Chairman and CEO of American Air Liquide, said in an Energy Forum episode with Ed Emmett at Rice University’s Baker Institute, “The world is always looking to make sure that energy is first available, it’s affordable, and then it’s clean. And I see hydrogen over time evolving in that manner.” He also noted that “companies have produced hydrogen and utilized hydrogen for over 100 years, and they’ve done that very safely… I think we can continue that moving forward.”

China has doubled down on hydrogen as part of its industrial strategy, building massive electrolyzer manufacturing capacity and funding dozens of pilot projects across transportation and heavy industry. Japan and South Korea also stand out as examples of how sustained policy support can drive hydrogen progress.

Where Hydrogen Fits Today

To understand hydrogen’s role now, it helps to remember what it actually does. About 76 percent of global hydrogen is produced from natural gas and used in refineries, fertilizer plants, and chemical production. This so-called “gray hydrogen” is essential but carbon-intensive.

What’s new is the rise of low-carbon hydrogen, “blue” hydrogen made from natural gas with carbon capture, and “green” hydrogen produced by splitting water with renewable electricity. These methods are expensive, but they’re growing. According to the International Energy Agency, global low-emissions hydrogen output rose about 10 percent in 2024.

Hydrogen is also expanding beyond industry. As Graff explained, it already powers thousands of forklifts in warehouses across the U.S. and is beginning to appear in commercial trucking, locomotives, and even aviation prototypes. “You can now drive 600 to 800 miles on a hydrogen fuel-cell truck,” he noted, “and refuel in 30 minutes, just like you would refill for diesel.”

The Cost Challenge and a Gulf Coast Opportunity

So why the slowdown? One word: economics.

Even with generous tax credits, green hydrogen can cost two to three times more than conventional fuels. Electrolyzers are still expensive, though costs are falling as Chinese suppliers introduce low-cost alternatives.

Infrastructure is another hurdle. Pipelines, storage, and fueling networks need to be built from scratch.

But those same challenges point to opportunity, especially along the U.S. Gulf Coast. The region already has one of the world’s largest hydrogen pipeline systems and a well-established energy infrastructure. Texas, in particular, has a head start. It already hosts nearly 1,000 miles of hydrogen pipelines, about 64 percent of the U.S. total, and some of the world’s largest hydrogen storage sites at Moss Bluff, Spindletop, and Clemens. Out of 140 hydrogen plants operating nationwide, 43 are in Texas, supported by extensive refining and natural gas infrastructure. This combination of assets gives the Gulf Coast an unmatched foundation to scale low-carbon hydrogen and integrate production, storage, and end use across industries.

As Ken Medlock , Senior Director of the Center for Energy Studies at Rice University’s Baker Institute, explains in his report: Developing a Robust Hydrogen Market in Texas, Texas has all the critical elements needed to lead in a low-carbon hydrogen economy, including existing infrastructure, a skilled workforce, and proximity to industrial demand centers. That combination gives it a distinct advantage in scaling up hydrogen production and use.

Governments around the world are showing renewed confidence in hydrogen. The European Commission awarded nearly €3 billion to 13 major projects, while Japan and South Korea continue expanding fueling networks. China is leading one of the most ambitious buildouts, with more than 50 planned hydrogen projects and a rapidly growing fleet of fuel-cell vehicles. Despite recent setbacks, global investment has surpassed $100 billion, and projects in places such as Chile, where strong renewables and low-cost Chinese equipment help make projects feasible, are moving toward final investment decisions.

What Comes Next

Hydrogen’s future won’t depend on replacing every fuel, but on filling the gaps where batteries and biofuels fall short.

Transportation: This is where momentum is strongest today. Batteries dominate cars, but hydrogen fuel cells excel in heavy trucks, ships, and planes. As Graff noted, “You can design a commercial vehicle with the same utility as diesel but powered by hydrogen.” Airbus and Boeing are testing hydrogen propulsion concepts, and several ports are experimenting with hydrogen bunkering for cargo ships.

Industry: Steel, cement, and chemicals account for a quarter of global emissions. Hydrogen-based direct-reduced-iron (DRI) steelmaking is being piloted in Europe and Asia and could transform how these materials are produced at scale.

Storage: Hydrogen can store energy for days or weeks, serving as backup for renewables like wind and solar. But storage remains very costly and may only prove viable for the “last mile” of greenhouse gas reduction or grid stability.

These uses may sound niche, but that’s how technologies scale. They start small, gain an economic foothold, and expand as costs decline.

Conclusion

Hydrogen's early, perhaps irrational, exuberance may have cooled, but amidst the rubble of cancelled projects are the beginnings of an industry that could play a vital niche role on the journey towards a lower carbon intensity energy future. As costs fall and infrastructure around the world expands, hydrogen's role will expand into the nooks and crannies of the energy industry.

It won't replace every fuel, but it doesn't have to. Success will come from steady, project-by-project progress.

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Scott Nyquist is a senior advisor at McKinsey & Company and vice chairman, Houston Energy Transition Initiative of the Greater Houston Partnership. The views expressed herein are Nyquist's own and not those of McKinsey & Company or of the Greater Houston Partnership. This article originally appeared on LinkedIn.

Houston energy startup launches to power AI data centers with Microsoft agreement

power move

Buoyed by a purchase agreement from Microsoft, Houston-based Joulent recently launched to build power plants that meet the electricity demands of AI data centers and other computing-heavy industries.

Joulent builds dedicated power-generating facilities that feed directly into data centers and other power-dependent facilities, eliminating the need for companies to siphon power from grids. Joulent’s plants combine generation, storage and smart controls in a modular, scalable setup, according to a news release.

Investment firm Engine No. 1 established Joulent in collaboration with energy technology company GE Vernova.

Joulent’s first project, the Project Kilby natural gas facility in West Texas, will be co-located with a Microsoft data center. It’ll deliver about 2.67 gigawatts of power under a 20-year deal between Microsoft and Energy Forge One, a subsidiary of Houston-based Chevron. Engine No. 1 and Chevron teamed up to build the plant.

GE Vernova will supply most of the plant’s power capacity, with additional capacity coming from Solar Turbines, a subsidiary of Irving-based construction and mining equipment manufacturer Caterpillar.

“Leadership in the AI era will be determined by who can deliver energy and compute the fastest, most reliably, and at the lowest cost,” Chris James, founder and CEO of Engine No. 1 and Joulent, said in a news release.

“By building new power-generating facilities, Joulent enables customers across industries to power the next chapter of American innovation, while reducing pressure on existing grids and maintaining affordability for ratepayers.”