top of page
DOCTOR-FOUNDRY-LOGO-STANDART-2025.jpg

Additive Manufacturing in Energy Generation: What 3D-Printed Turbines Are Teaching the Modern Foundry Professional

A Discovery That Goes Beyond Energy


In May 2026, Oak Ridge National Laboratory (ORNL), in partnership with Cadens — a startup based in Rome, Wisconsin — published a success story that made headlines worldwide: large-scale hydraulic turbines manufactured with 3D printing, capable of unlocking up to 29 GW of dormant hydroelectric power stored across approximately 90,000 American dams that currently generate not a single watt of electricity.




The news spread quickly across technology and energy outlets. But for the foundry and metallurgy community, there is a deeper layer worth unpacking — and that is exactly what this article is about.



What Was Actually Done, Technically?

The ORNL + Cadens collaboration deployed BAAM (Big-Area Additive Manufacturing) technology — an industrial-scale large-format 3D printer capable of depositing dozens of pounds of material per hour, producing components several feet in length.

The manufactured components included:


  • Draft tube — printed in ABS reinforced with 20% carbon fiber, in two sealed halves, resulting in a robust 688 lb unit

  • Runner housing — a 3D-printed mold used for subsequent fiberglass casting

  • Pipe supports, wall thimbles, end fittings, and runner system — for the Fixed-Kaplan S-turbine design

  • Primary waterway — a large-diameter PVC pipe as the main flow channel


The outcome: up to 40% reduction in cost per kilowatt compared to traditional manufacturing methods, with a prototype that has operated continuously for more than six years at Cadens' test facility, generating real-world performance data.


The Intersection With Foundry: Why This Case Matters to You


1. 3D Printing as a Foundry Tool — Not a Replacement

This is the most important point — and the most frequently misunderstood.

In the ORNL/Cadens project, additive manufacturing did not eliminate casting — it enhanced it. The runner housing, for example, used a 3D-printed mold for fiberglass casting. This is precisely what the foundry industry already knows as rapid tooling or additive tooling: 3D printing produces the tooling; casting produces the final part.


For U.S. foundries, this represents a concrete opportunity:

  • Dramatic reduction in pattern and core box lead times

  • Complex geometries that once required months of machining can be realized in days

  • Faster design iterations, lowering the cost of new product development


The TVA (Tennessee Valley Authority) has been an early mover in this space, working alongside ORNL to apply additive manufacturing to the modernization of legacy dam infrastructure across the Southeast — a model that other utility operators and their supply chains are already watching closely.


2. The Materials Question: Polymer Composites vs. Metals

The Cadens project used carbon-fiber-reinforced ABS polymer — not metal. This was a deliberate choice for non-critical components under lower structural loads. For high-performance components — stainless steel runners, for example — ORNL is simultaneously running the Rapid RUNNERS program, which uses robotic layer-by-layer metal deposition (DED — Directed Energy Deposition) to fabricate Francis runners weighing up to 46 tons.


Here, traditional foundry is not just relevant — it is indispensable. The runners for large-scale turbines at TVA facilities, such as Wilson Dam (653 MW, 21 generating units), continue to be produced through processes that involve molding, casting, and precision metallurgical finishing. The ORNL program explicitly aims to bring this manufacturing back to U.S. soil, reducing dependence on overseas casting.


3. Tooling Costs and the Economics of Small Series Production

The key economic bottleneck for small-scale hydropower has always been the same one faced by any job-shop foundry: site-specific tooling costs make small production runs economically unviable.


The ORNL/Cadens solution — balancing standardization with customization — is exactly the same logic that high-performance foundries apply every day. Their approach centered on a standardized PVC pipe as the primary waterway, with specialized 3D-printed polymer components built to match its dimensions. The result was a modular system that could be adapted to any low-head site without starting from scratch.


Additive manufacturing doesn't solve this problem alone; it is an additional tool in the modern foundry professional's arsenal — one that makes the economics of customization finally pencil out.


The U.S. Landscape: Scale, Opportunity, and Industrial Impact


Of the approximately 90,000 dams in the United States, fewer than 3% currently generate electricity. Around 51,000 of those are classified as having micro-hydropower potential — capable of producing up to 100 kilowatts each. The aggregate untapped potential reaches 29 GW: more than twice the output of Hoover Dam.

The barriers were never geological or hydrological. They were manufacturing and economic. Custom hydraulic turbines have traditionally been expensive to design and produce, with long lead times driven by the cost of site-specific tooling and the complexity of fabricating components to tight hydraulic specifications.


The ORNL/Cadens breakthrough directly attacks those barriers:

Traditional Manufacturing

BAAM-Enabled Manufacturing

Months-long lead times

Days to weeks

High tooling cost per unit

Shared tooling across sites

Fixed geometries

Fully customized per site

Cost-prohibitive for <100 kW sites

Viable at micro scale

Overseas supply chains

U.S.-based production

This is not a hypothetical future scenario. The prototype at Cadens' test facility in Sullivan, Wisconsin has been running continuously since installation — generating electricity and data that are already informing the next generation of design.


What the Rapid RUNNERS Program Means for U.S. Foundries

Beyond the micro-hydro application, ORNL's Rapid RUNNERS program targets the large-scale end of the spectrum — and it has direct implications for American foundries and their metalcasting supply chains.


The program aims to 3D print Francis runners for TVA dams using robotic welding to deposit stainless steel layer by layer. Three runners are planned:

  • A prototype runner for laboratory testing

  • A 5-foot-diameter runner for potential installation at TVA's Ocoee Dam (24 MW, 5 generating units)

  • A 46-ton runner for TVA's Wilson Dam (653 MW, 21 generating units)


Adam Stevens, R&D staff member at ORNL and technical lead for the project, described the potential plainly: "This has the potential to transform forging and casting of large-scale metal components."


For foundries in the Tennessee Valley and beyond, this isn't a threat — it's a signal. The U.S. government is investing in domestic manufacturing capability for critical energy infrastructure. Foundries that position themselves at the intersection of traditional metalcasting and directed energy deposition will be the ones writing the supply agreements.


The Takeaway for Foundry Professionals


The narrative that "3D printing will replace casting" is, once again, being contradicted by real-world practice. What is actually happening — and what the ORNL/Cadens project makes unmistakably clear — is technology integration.


Foundries that master the interface between additive manufacturing and their core processes (sand casting, die casting, gravity casting, investment casting) will be at the forefront of a market that increasingly demands:

  • Complex geometries that can only be produced with additively generated tooling or molds

  • Shorter development cycles, enabled by rapid tooling prototyping

  • Smaller, customized production runs, made viable by reduced tooling costs


The U.S. government is funding this convergence directly through the DOE's Advanced Materials and Manufacturing Technologies Office. The supply chain opportunity is real, it is funded, and it is already operating — 688 pounds at a time, inside a Wisconsin mill that has been running on river water since 1842.

3D printing doesn't print the future of foundry. It molds it — literally.


Doutor Fundição is the leading technical platform for the global foundry and metallurgy community, delivering free content, workshops, seminars, and a thriving professional network. Visit www.doctorfoundry.com and join us.


DOCTOR FOUNDRY The world of foundry




Sources and Further Reading

This article was built from multiple technical and journalistic sources. All links are listed below for readers who want to go deeper:

1. Primary Source — Oak Ridge National Laboratory (ORNL) Official ORNL publication with full technical project details: 🔗 https://www.ornl.gov/success-story/3d-printing-lowers-costs-expands-hydropower-opportunities

2. Interesting Engineering — International Technical Coverage Component-level breakdown and specifications of the ORNL/Cadens project: 🔗 https://interestingengineering.com/energy/3d-printed-turbines-for-hydropower-plants

3. VoxelMatters — Additive Manufacturing Specialist Publication Analysis of BAAM's impact on hydraulic component cost reduction: 🔗 https://www.voxelmatters.com/ornls-manufacturing-demonstration-facility-uses-additive-manufacturing-to-cut-hydropower-component-costs/

4. Additive Manufacturing Media — Industry Trade Publication Full history of the Cadens + ORNL partnership and BAAM development for micro-hydropower: 🔗 https://www.additivemanufacturing.media/articles/how-large-format-3d-printing-supports-micro-scale-hydropower

5. 3D Printing Industry — ORNL Rapid RUNNERS Program Details on large-format metal additive manufacturing of runners for the TVA: 🔗 https://3dprintingindustry.com/news/ornl-to-3d-print-large-scale-hydropower-turbine-components-in-a-new-doe-funded-project-232641/

6. Newswise / ORNL Press Release Official DOE/ORNL press release with project summary and imagery: 🔗 https://www.newswise.com/articles/3d-printing-lowers-costs-expands-hydropower-opportunities





Comments

bottom of page