Every engine, every factory, every power station and even every laptop spills heat into the air. In fact, more than half of the world’s primary energy use is lost as waste heat. Imagine if we could capture even part of that and turn it into electricity. That’s the promise of thermoelectric devices, which convert heat differences directly into power.
The trouble is, most thermoelectric devices are bulky, inefficient, or too costly for widespread use. Now, researchers reviewing the latest advances suggest that a surprising ally, 3D printing, could give thermoelectrics the breakthrough they need.
Why Lattice Structures?
The new review focuses on lattice structures: lightweight, repeating 3D frameworks that can be precisely shaped using additive manufacturing. Think of a honeycomb, but engineered at scales from millimetres down to microns.
In thermoelectrics, the goal is to manage two conflicting needs:
- Allowing electrical charges to flow freely (to generate current).
- Restricting heat flow (to keep the temperature difference alive).
3D-printed lattices make it possible to design materials that block heat but conduct electricity, an optimisation that traditional manufacturing struggles to achieve.
What’s New in This Research
The review highlights several exciting advances:
- Custom geometries: 3D printing can create intricate patterns that finely tune thermal and electrical transport.
- Material efficiency: Lattice designs use less raw material without sacrificing strength, making devices lighter and cheaper.
- Integration potential: Printed structures can be embedded directly into components, from exhaust systems to microelectronics, capturing heat exactly where it is wasted.
- Scalability: Early demonstrations show that additive manufacturing could bring thermoelectrics out of the lab and into industrial applications.
Why It Matters for a Sustainable Future
Thermoelectrics won’t replace wind or solar, but they could make the entire energy system more efficient. From car engines to steel plants, from data centres to home appliances, waste heat is everywhere. Each watt recovered means less fuel burned, fewer emissions released, and more renewable capacity freed for other uses.
3D printing’s role is to unlock design freedom: by building devices with shapes impossible to make otherwise, we can push performance beyond old limits. This makes thermoelectrics not just a curiosity, but a practical tool in the broader clean energy toolkit.
The Takeaway
The energy transition is not just about building more wind turbines and solar panels, it’s about wasting less of what we already produce. By pairing thermoelectrics with 3D-printed lattices, researchers are pointing towards a world where even waste heat becomes part of the solution.
Source
3D-printed lattice structures for thermoelectric devices – a review, Journal of Materials Science: Energy and Sustainability, 2025-07-25.
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