Data Center Equipment Supply Chain Constraints: Turbines, Transformers, Chillers and Chips

For most of the last decade, the long pole on a data center project was the utility: how long it took to study a new load and build the lines and substation to serve it. That is still true in many places, but a second clock now runs beside it. The equipment that turns a utility commitment into a working campus (transformers, breakers, switchgear, generators, chillers, and for on-site power, turbines or engines) has its own multi-year queue.

The International Energy Agency’s 2026 review of energy and AI says supply chains for gas turbines and transformers, as well as advanced chips and IT components, tightened over the past year, and that the volume of proposed data center projects is straining planning and grid connection processes.¹ In practice, a project can have a signed electric service agreement and still miss its power date because the main power transformer will not ship in time.

This guide covers the equipment categories that most often set the critical path, what public sources report about each as of 2026, and how the constraints feed back into which sites are worth pursuing. For the transformer and switchgear detail on its own, see our guide to transformer and switchgear lead times.

Gas turbines matter to data centers in two ways: utilities need them to build new generation for large loads, and developers want them for on-site or bridge power. Both groups are ordering from the same three heavy-duty manufacturers. Reporting on the IEA’s findings says orders for gas turbines to power data centers rose about 70% in 2025.⁹

GE Vernova reported a gas power backlog of 116 GW at the end of the second quarter of 2026, up from 100 GW a quarter earlier and 83 GW at the end of 2025. About 53 GW was firm equipment backlog and about 63 GW was slot reservations, in which customers pay to hold a future production slot.³ Siemens Energy reported a 69 GW gas turbine backlog with lead times of three years or more, and Mitsubishi Heavy Industries reported 35 GW of large-frame backlog, with recently booked orders scheduled for delivery between 2028 and 2030.¹⁰

Wood Mackenzie has estimated global manufacturing capacity at roughly 60–70 GW a year against about 110 GW of orders, and lead times for new combined-cycle plants have been reported at around five years, up from about three and a half in 2023.¹⁰ The practical effect is that smaller machines are taking roles once reserved for large frames: aeroderivative turbines and reciprocating engines are moving from backup duty toward primary power at some hyperscale projects.¹¹ Our comparison of gas turbines and reciprocating engines covers that trade-off.

Every campus needs large transformers: the main power transformers in the utility or customer substation, and many smaller units that step medium voltage down inside the campus. Wood Mackenzie’s Q2 2025 survey put average lead times at 128 weeks for power transformers and 144 weeks for generator step-up units, while distribution transformer supply has improved.² Its modeling points to supply deficits of about 30% for power transformers and 10% for distribution transformers in 2025.²

Demand is the driver. Wood Mackenzie reports that U.S. demand for generator step-up units rose 274% and for substation power transformers 116% since 2019, that imports supply roughly 80% of U.S. power transformers, and that some high-capacity units are quoted at up to four years.⁴ It also projects U.S. data center capacity rising to about 110 GW by 2030 from around 24 GW, which keeps pressure on the highest-voltage equipment classes.⁴

Switchgear and circuit breakers are the next bottleneck. Reuters reported that utilities are scrambling to lock in equipment as data center demand strains supplies, with analysts expecting breakers and switchgear to face larger deficits.¹² Lead times quoted for medium-voltage switchgear built to data center specifications vary widely by manufacturer and configuration, so written quotes for the exact specification are the only reliable number.

Backup generators

Large diesel generator sets remain the default backup for most campuses. A September 2026 trade analysis, citing manufacturer order books, put lead times at roughly 18–24 months for units above 2.5 MW; treat that as an estimate rather than a published manufacturer figure.⁵ Cummins reported record Power Systems revenue of $2.3 billion for the second quarter, citing strong demand for data center backup power, a multiyear agreement with a hyperscaler covering several gigawatts of future generator demand, and capacity limits on larger generator configurations through 2026.⁶

Chillers and cooling equipment

Cooling manufacturers are reporting order books that outpace shipments. Vertiv’s backlog roughly doubled over 2025 to about $15 billion.¹³ Trane Technologies acquired Stellar Energy, which brought about $1 billion of backlog and modular chiller products aimed at data centers.¹⁴ For sites, the shift toward liquid cooling and modular, factory-built cooling plant can shorten field construction but ties the schedule to a factory slot.

GPUs and IT equipment

Chips are a different kind of constraint. They do not sit on the site’s critical path the way a transformer does, but they set how fast buyers want capacity and where they will pay for speed. Coverage of the IEA’s 2026 findings notes a shortage of high-bandwidth memory used in AI accelerators that is expected to last through at least the end of 2027.¹⁵ When accelerators are scarce and expensive, an idle powered building is costly, which pushes buyers toward sites that can energize on a firm date.

Much of the electrical equipment a campus needs is imported or built from imported metals, so trade policy moves both cost and timing. A 50% Section 232 tariff on copper took effect on August 1, 2025, and steel and aluminum tariffs were raised to 50% in 2025 and extended to many derivative products.⁷ Copper is central to transformer windings, switchgear, busway and cable, and steel and aluminum run through enclosures, racks and cooling equipment.⁷

An April 2026 proclamation restructured the metals tariffs again. For goods entered on or after April 6, 2026, duties apply to the full customs value of covered products, including derivatives, at tiered rates that depend on metal content, and hundreds of low-metal products were removed from scope.⁸ Rates, product coverage and expiration dates have shifted several times since early 2025, so a project budget should be checked line by line with a customs broker or trade counsel rather than built on a single headline rate.

The figure below summarizes reported lead times for the long-lead categories discussed above. Ranges reflect averages and upper quotes from different sources and dates, so they are a planning frame, not a quote.

Two cautions apply. Averages hide the specialized units that data centers often need, such as high-capacity transformers and data center specification switchgear. And a quoted lead time usually starts when the order is released with approved drawings, so engineering, submittals and approvals add time before the factory clock starts. Our guide to the energization timeline shows where these fit.

The categories also interact. A campus waiting on a main power transformer gains little from early generator delivery, and on-site generation that arrives before its switchgear cannot carry load. The useful exercise is to list every long-lead item for the first phase, attach a realistic order date and delivery window to each, and find the latest one. That item, not the average, sets the earliest credible date to energize.

Equipment scarcity changes which sites rise to the top of a shortlist. When every new substation and generator needs a multi-year factory slot, a site that avoids some of that equipment, or already has it, is worth more.

• Existing infrastructure counts. Retired plant sites, existing substations and powered land can reuse transformers, switchyards and interconnection rights. See surplus interconnection and retired plant sites.
• On-site power depends on equipment you can actually get. Heavy-duty turbines are booked years out, so plans increasingly rely on engines, aeroderivatives or phased generation.¹¹ Our guide to on-site generation and bridge power covers the options.
• Phasing helps. A ramp schedule that starts with the load existing equipment can serve buys time for later units.
• Buyers with slot reservations move faster. Large developers and hyperscalers that pre-order equipment can match a site to equipment they already hold.³

For a landowner or early-stage developer, the useful questions are what equipment the site needs that does not exist today, who will own and order it, and whether the utility’s schedule assumes equipment already on order. If you want an outside view of a parcel, you can get a site reviewed.