In the global race to net zero, the built environment remains both a persistent challenge and a promising frontier. Responsible for nearly 40% of global greenhouse gas emissions, buildings have long been under scrutiny, not just for how much carbon they emit during operation, but also for the embodied carbon embedded in the materials used to construct them.

So, what happens when a building material doesn’t just store carbon more efficiently, but also generates electricity from heat?

That’s exactly the kind of future we’re edging closer to, thanks to a remarkable advancement from researchers in China. A team led by Professor Zhou Yang at Southeast University has developed a thermoelectric cement-hydrogel composite that converts ambient heat into usable electricity. In other words, they’ve turned cement into a power source.

Let me unpack what this means and why it could fundamentally transform the built environment’s path to decarbonisation.

The New Role of Building Materials

Traditionally, materials like concrete and cement have been passive contributors to a building’s structure. Heavy lifters in terms of strength, durability, and insulation, but largely inert in energy systems. Their primary sustainability challenge? High embodied carbon, particularly in cement, whose production alone accounts for around 8% of global emissions!

Now, imagine a building material that doesn’t just take up energy during manufacture, but actively generates it during use.

That’s the promise of this new cement-hydrogel composite, inspired by the microstructure of plant stems. By alternating layers of conventional cement with a polyvinyl alcohol (PVA) hydrogel, researchers achieved a Seebeck coefficient of -40.5 millivolts per Kelvin—ten times greater than any known cement-based thermoelectric material to date.

In essence, this material captures the differences in heat, between a sunny rooftop and a cool interior, as an example, and converts that thermal gradient into electricity. Not only can it generate power; it also stores it.

The implications are profound.

Embedding Intelligence in Infrastructure 

This innovation is about more than just energy harvesting, it’s about creating infrastructure that thinks, responds, and operates independently. By combining energy generation with energy storage, this smart material has the potential to power sensors and low-power electronics embedded directly within the structure of a building.

Imagine the possibilities:

• Bridges that power their own structural health monitoring systems
• Pavements that generate power from day-to-night temperature changes
• Walls that feed energy to embedded environmental sensors or emergency lighting
• Industrial facilities with self-powered, wireless IoT networks for safety and performance monitoring

In many cases, these applications remove the need for batteries, hardwired connections, or grid dependency altogether, dramatically improving resilience and reducing both costs and emissions.

This kind of decentralised, building-integrated intelligence isn’t just useful. It’s a necessity for the sustainable cities of the future.

Decarbonising the Built Environment 

To understand how this fits into the broader sustainability picture we need to revisit how we measure and reduce emissions across a building’s lifecycle.

Historically, efforts focused heavily on operational carbon, coming from the energy used to heat, cool, and power a space. This made sense, particularly before the rise of renewables. But as grid decarbonisation progresses and energy efficiency improves, embodied carbon, the emissions from producing, transporting, and assembling materials has emerged as the next frontier.

That’s where “whole-life carbon” assessments comes in, accounting for both operational and embodied emissions from design to demolition. But in practice, this shift has led to a major challenge: balancing reductions in embodied emissions without increasing operational burden, or vice versa.

This is what makes multifunctional materials so exciting.

Instead of just mitigating embodied carbon, this new cement actively offsets operational carbon, creating a dual benefit. Better yet, it opens the door to regenerative design: buildings that contribute more to the energy system than they take.

As sustainability professionals, we’re often asked: “How can construction be part of the solution, not just the problem?” Materials like this offer a powerful answer.

Opportunities for Industry Transformation

The practical applications of this cement-hydrogel innovation could be widespread, but realising its potential will require systemic change.

First, specifiers and architects must be empowered to evaluate materials not just by cost and strength, but by multifunctional performance metrics, including thermoelectric efficiency and lifecycle carbon benefits. As digital tools like BIM (Building Information Modelling) platforms become more sophisticated, we’ll need to integrate this type of data directly into design workflows.

Second, policymakers and buyers should start to incentivise materials that deliver beyond baseline performance. If we’re serious about meeting net zero by 2050 or sooner, we need procurement strategies that reward innovation, not just compliance.

And finally, developers and infrastructure planners must look beyond traditional ROI models. When a material can reduce energy bills, power digital systems, and cut carbon all at once, we’re talking about value far beyond the cost per tonne or square metre.

Barriers and Breakthroughs 

Of course, we’re still in the early days. Like any scientific breakthrough, this cement-hydrogel technology will need to be scaled, validated in real-world environments, and tested for durability, performance, and integration with other building systems.

But it’s worth noting that this innovation didn’t emerge in isolation. It builds on decades of research in material science, bioinspired design, and thermoelectric technology. It reflects a growing trend: the convergence of sustainability, smart tech, and materials science to reshape what buildings can be.

This is not a fantasy of far-off cities. It’s an urgent call to rethink the role of materials in the built environment, right now.

The Road to Smarter, Self-Sufficient Cities 

As we transition to a low-carbon economy, the materials we choose will define our trajectory. We can no longer afford for cement to be inert and walls to be lifeless. The future is intelligent, integrated, and multifunctional.

With advancements like this cement-hydrogel composite, the line between infrastructure and technology continues to blur. And that’s exactly what we need. Not just net-zero buildings, but buildings that actively contribute to the zero-carbon transition.

This innovation reminds us that the solutions to climate change are not only found in boardrooms or policy documents. Sometimes, they’re found in the simplest of things, like cement… but reimagined.

Alan Stenson, CEO

Neutral Carbon Zone