Under the Radar

91% of revenue from AI processors (71%) and silicon photonics (20%). Record $80.6M backlog driven by a $41M hyperscaler burn-in order. FY2027 guided $130-150M, nearly 3x FY2026.

Aehr Test Systems designs and manufactures burn‑in and test systems used to screen semiconductor devices for early‑life failures. Its equipment stresses chips at high temperatures and power levels to simulate years of operation in days, catching defects before the chips are packaged or shipped. As AI accelerator power and transistor density rise, burn‑in becomes essential for yield and reliability, and Aehr’s systems are among the few capable of testing wafers at thousands of amperes.

Building a 1.2 GW power plant for Applied Digital under a documented LNTP agreement. Bookings surged 1,900% to $2.5B with a pipeline exceeding $14B dominated by AI data center power.

Babcock & Wilcox engineers and manufactures steam‑generation boilers, environmental systems, and aftermarket services for utilities, industrials, and data‑centre developers. Founded nearly 160 years ago, the company’s equipment provides the baseload thermal power behind the AI buildout — from coal and natural gas plants to hybrid designs that allow later combustion‑turbine addition.

Precision gearing and sub-assemblies for natural gas turbines powering data centers. Orders up 66% with backlog at record levels, customers sold out through 2030. GE Vernova is a disclosed top customer.

Broadwind designs and manufactures precision gearing, custom gearboxes, and fabricated sub-assemblies for gas turbine OEMs, serving the power generation infrastructure that underpins AI data center expansion. Its high-speed reduction gearing is integral to natural gas turbines, while its Industrial Solutions unit provides kitting, supply-chain management, and assembly services for the same customers.

North America's largest metal fabricator, pivoting into data center electrical infrastructure. DC segment grew 71% organic with $50M in new awards in Q1 alone, approaching 25% of revenue by Q4.

Mayville Engineering Company is the largest metal fabricator in North America, ranked #1 on the FAB 40 list for sixteen consecutive years. It takes raw steel and aluminum and — through cutting, bending, welding, machining, painting, and assembly — produces the metal components, enclosures, frames, and sub‑assemblies that form the structural and electrical backbone of heavy trucks, construction equipment, agricultural machinery, and data centers. Its datacenter & critical power segment manufactures Power Distribution Units (PDUs), static transfer switches, switchgear, busway components, and cooling enclosures for hyperscale and colocation data centers, making it a direct supplier to the AI infrastructure buildout.

Provides modular workforce housing for data center and power plant construction crews. Over $2B in contract awards since Feb 2025, including a $750M AI infrastructure community. Pipeline of over 20,000 beds.

Target Hospitality designs, deploys, owns and operates modular workforce accommodation communities—dormitory‑style units with integrated food, housekeeping and security services—at remote sites where traditional hotels do not exist. Originally built for oilfield and government use, the platform is now being redirected toward the AI build‑out, serving the construction workforce of hyperscale data centers and the power plants that feed them.

Behind-the-meter power infrastructure for AI data centers. Documented 25 MW Powered Shell agreement with Crusoe for AI/HPC workloads. $1.35B backlog, over 80% owned assets.

Energy Vault is an integrated energy and power infrastructure company that designs, deploys, and operates energy storage systems and AI‑ready power infrastructure. Its core product, B‑VAULT, is a lithium‑ion battery energy storage system, complemented by the VaultOS energy management software suite. The company also offers Powered Land and Powered Shell solutions that provide turnkey power and cooling for AI data centers, addressing the critical bottleneck of power availability for hyperscale compute.

One of the world's two largest merchant photomask manufacturers. High-end IC masks hit record $71M (+19%) in Q1, with AI demand cited as the driver. $330M in U.S. and Korea fab expansions.

Photronics is an independent manufacturer of photomasks—quartz plates carrying the microscopic patterns that define each layer of a semiconductor chip. Without a photomask, no chip design can move from blueprint to wafer. As AI processors adopt ever-smaller nodes and more complex architectures, the precision and volume of masks required multiply, making photomasks a recurring, non-discretionary input for the semiconductor supply chain.

27% of Q1 bookings came from data centers, up from under 5% recently. Won a $30M+ hyperscaler fabricated-package project. Building a dedicated national data center vertical team in H1 2026.

Limbach designs, delivers, and maintains mechanical, electrical, plumbing, and controls (MEPC) systems for buildings — specifically for mission‑critical facilities where downtime is not an option. Its work encompasses everything from HVAC and power distribution to building automation, serving hospitals, industrial plants, universities, and an expanding roster of data‑center operators. The company’s core offering is owner‑direct relationships (ODR), where it partners directly with facility owners to maintain and upgrade existing infrastructure, providing a recurring‑like revenue stream.

Concrete segment builds structural foundations for hyperscale data centers at roughly 40% of segment revenue. Concrete segment grew 73%, with active project count rising from 40 to over 50 in six months.

Orion Group Holdings is a specialty construction company operating two complementary segments. The Marine segment provides engineering, construction, dredging, and specialty services for government and private clients, focusing on port terminals, Navy waterfront facilities, bridges, environmental restoration, and dredging. The Concrete segment delivers structural concrete, site civil, earthwork, and underground utilities for commercial, industrial, and public projects, with hyperscale data centers as its largest end market. Both segments address large-scale, mission-critical infrastructure needs tied to national security, global trade, energy export, and the AI buildout.

Supply Technologies segment approaching $150M annually from AI data center customers, primarily switchgear manufacturers. This was near zero two years ago. Operates under sole-source contracts.

Park‑Ohio Holdings Corp. is a diversified international industrial company operating through three segments. Through its Supply Technologies segment, it serves as a sole‑source supply‑chain partner to OEMs, managing the flow of fasteners, Class‑C components, and logistics; this segment is the primary vehicle for AI‑related revenue, serving switchgear and electrical distribution customers in the data‑center space. The Engineered Products segment manufactures induction heating and melting systems, forging presses, transformers, and generators — equipment used in data‑center power regulation and cooling, as well as in defense, steel, and oil & gas end‑markets. Assembly Components designs fuel‑rail and filler‑pipe systems for automotive OEMs, with growing exposure to electrified platforms.

Leading carrier-neutral data center operator in China transitioning to hyperscale AI. Wholesale revenue surpassed retail for the first time, growing 58%. New wholesale orders of 519 MW YTD 2026.

VNET Group is a leading carrier‑neutral data centre operator in China that builds, owns, and operates large‑footprint wholesale campuses and retail colocation facilities. Its wholesale IDC segment supplies internet giants and cloud providers with high‑density, megawatt‑scale capacity designed for AI training and inference workloads. The company also runs a retail colocation business and serves as Microsoft’s exclusive cloud partner for Azure, Microsoft 365, and Dynamics 365 in mainland China. With a total resource pipeline of 2.48 GW and plans to add another 1 GW, VNET is one of the largest independent providers of the physical infrastructure that China’s AI build‑out depends on.

D-VAR power quality systems protect fabs from voltage transients ($2-10M per fab). Made its first direct data center delivery in Dec 2025. Revenue $299M (+34%), fifth consecutive quarter of GAAP profitability.

AMSC designs and manufactures power-control equipment that protects electrical grids, semiconductor fabs, and naval vessels. Its technology combines proprietary smart materials and software to deliver compact, fast-acting solutions that prevent voltage instability and power failures — critical for the reliability of AI infrastructure.

High-horsepower diesel engines for data center backup generators through the MTU Yuchai JV. Generator volumes surged from roughly 750 in 2024 to over 2,000 in 2025. Higher margin than company average.

Yuchai is one of the largest independent engine manufacturers in China, producing diesel, natural-gas, and alternative-fuel engines ranging from light-duty units to 20-cylinder high-horsepower engines. Its engines power trucks, buses, off-road equipment, marine vessels, and generator sets. The company plays a role in the AI infrastructure buildout through high-horsepower diesel engines that serve as backup power for data centers, a fast-growing segment.

Precision motion components and power quality solutions including harmonic filters for data center infrastructure. Record bookings of $158M in Q1 (+15%) with book-to-bill of 1.14x and $251M backlog.

Allient Inc. designs, manufactures, and sells precision and specialty controlled motion components, modules, and systems. The product portfolio spans motors, drives, positioning stages, power quality filters, encoders, gearing, and industrial safety modules. Its equipment is used where precise motion or clean power is critical: industrial automation, AI-enabled data centers, surgical robots, and defense systems.

Optical networking platform developing the LiteWave800, an 800G coherent pluggable designed for intra-data-center AI compute with over 90% power reduction. Optical segment grew 24%.

ADTRAN provides optical transport, data‑center interconnect, and broadband access hardware, software, and services. Its products include coherent pluggable optics, optical transport platforms like the FSP 3000 family, residential gateways, Wi‑Fi 7 access points, and the Mosaic One cloud‑based network management platform. Customers range from rural telecom operators to hyperscale cloud providers, with the optical portfolio increasingly sold into AI‑driven data‑center expansions.

Engineering services for hyperscale data center site development. Data center revenue has more than doubled to over 6% of total. Backlog $653M (+56%, entirely organic). Three recent acquisitions targeting DC power engineering.

Bowman provides multidisciplinary engineering, technical consulting, program management, geospatial, and advisory services to owners and operators of the built environment. Its work spans building infrastructure, transportation, power & energy, and natural resources; a fast‑growing cross‑segment activity serves hyperscale and colocation data centers. The firm’s role in AI infrastructure is direct but early — site‑civil engineering, power interconnection studies, and construction‑phase program management — accounting for just over 6% of total revenue while more than doubling in a year.