Applied Digital 포함 AI 데이터센터 운영사들이 극한의 열·전력 부하 수요를 충족하기 위해 현장 발전용 산업 규모 보일러와 스팀 터빈을 배포하고 있다.

Artificial intelligence data centers are proliferating at an unprecedented pace, with more than 12,000 active projects in the U.S. currently seeking grid interconnection representing 1,570 GW of generator capacity and 1,030 GW of energy storage. Analyst firm Omdia predicts that AI will drive more than 50% of installed power generation capacity over the next five years. A survey by Black & Veach found that lack of power is the biggest obstacle for data centers: 53% of utilities cited available power as the top constraint, with transmission (47%) and substation upgrades (46%) close behind.

In response, data center developers have pursued gas turbines, either to power their own facilities or to strengthen regional grid capacity. But equipment lead times are prohibitive. "Orders for gas turbines today might not be delivered until 2032," said Wes Cummins, chairman and CEO of Applied Digital, which operates multiple GW of data centers either live or under construction in Ellendale and Harwood, North Dakota. Unable to wait, Applied Digital has instead ordered 1.2 GW of steam turbines fed by gas-fired industrial boilers for another North Dakota data center, with two additional facilities being finalized. The first is scheduled to begin operation in late 2028. This $2.4 billion design-build agreement was signed in conjunction with independent power producer Base Electron.

"You need a lot of power for an AI data center, whether it is one focused on training of AI models or on delivering AI results to users (known as inferencing)," Cummins said. "To deal with the scale of AI, the boiler and steam turbine combination is proven." When gas turbines eventually become available in a few years, Applied Digital plans to convert these facilities into combined cycle plants to boost efficiency. The boiler steam will supplement steam produced using exhaust heat from the gas turbine in a heat recovery steam generator (HRSG).

To accelerate deployment, packaged boilers are preferred. Rather than being built onsite, they are manufactured and assembled in factories with burners and controls, then shipped as complete systems requiring only minor installation and basic connections for fuel, water, and electricity. For boilers too large for transport, they are assembled into modules for final integration on site, with work still largely nominal. "Boilers and steam turbines can currently be delivered faster than other generation solutions," said Cummins.

Rentech Boiler Systems of Abilene, Texas, can manufacture and deliver a packaged boiler within a year of receiving an order, according to Gerardo Lara, the company's vice president of Boiler Sales. Rentech has delivered more than 1,000 boilers and HRSGs over 30 years, ranging from 20,000 to 650,000 pounds per hour of steam at pressures from 200 to 2,000 psi. Its models suit steam turbines from 10 MW to 20 MW, with modularized designs accommodating turbines up to 50 MW, available from many suppliers. "There are two basic design types for packaged boilers: fire-tube and water-tube," Lara explained. "The former is generally better for smaller commercial loads and the latter for higher pressure and temperature capacities in industrial applications." Rentech produces fired watertube models with water-cooled, full membrane wall construction providing low maintenance and tight gas-side seals.

"The packaged boiler is the workhorse of the industry, the market is very strong, and there is plenty of interest from the data center community," Lara said. "A boiler and steam turbine offers typical Rankine cycle efficiency." The company offers conservatively designed boilers with large furnaces ensuring optimal circulation, efficient heat transfer, and substantial steam delivery while meeting emission guarantees. Steam drums are built for high retention times and robust internals, lowering facility maintenance burdens. When paired with a steam turbine, the boiler burns natural gas and turns water into steam. Tubes, channels, and drums feed steam directly to the turbine at the required temperature and pressure to generate electricity.

"We have been very busy over the past year with lots of projects being done for data centers," Lara said. "With such a long backlog on gas turbine delivery, there is rising interest in pairing packaged boilers with steam turbines to deliver the vast amount of energy consumed by AI."

The gas turbine backlog is severe. GE Vernova reported more than 100 GW of orders and slot reservations. Despite adding shifts, investing billions in new manufacturing capacity, and streamlining production, the company cannot keep pace. Siemens Energy, Solar Turbines, and Mitsubishi Power report similar delays. Yet data center developers continue ordering gas turbines while hedging bets—purchasing gas engines in record numbers alongside fuel cells, battery energy storage systems, renewable energy, geothermal power, nuclear small modular reactors (SMRs), and any other promising source.

The boiler-steam turbine combination is a relatively new tool for developers. Both represent proven technology with much shorter lead times—typically a year or less for packaged boilers—and good capacity. Industrial boilers have existed for decades with extensive supply chains and manufacturing experience across boom-bust cycles, positioning them for rapid production increases. A broad range of steam turbine manufacturers exists: Siemens Energy, GE Vernova, Mitsubishi Power, Howden, Ebara Elliot, Doosan Skoda, Toshiba Energy, Shanghai Electric, Everllence (formerly MAN), Baker Hughes, Triveni, and Bharat, all with well-established supply chains.

According to McCoy Power Reports, steam turbine production peaked in 2015 at close to 140 GW of units at least 5 MW, falling below 50 GW by 2019 and not yet fully recovering. This suggests roughly 50 GW of increased manufacturing capacity potential in the existing supply chain. Once data center developers learn of this capacity, it will likely evaporate quickly; steam turbine order backlogs may extend out similarly to gas turbines within a couple of years.

This is already occurring for very large units. Nuclear plant reopenings are driving demand for steam turbines above 1 GW, while record combined cycle plant buildouts demand turbines larger than 300 MW. Many SMR projects under development are creating renaissance demand for turbines in the 150 MW to 300 MW range. Mid-sized and smaller turbine sectors retain significant spare capacity, though for how long remains uncertain. Global Market Insights predicts the steam turbine market will grow substantially in the coming years.