The World Economic Forum selects 100 early- to growth-stage startups each year as part of its Technology Pioneers program, spotlighting innovations across climate science, renewable energy, decarbonization, and healthcare. The 2024 cohort spans 23 countries with a strong focus on artificial intelligence and smart-energy solutions. Among these pioneers are three companies developing technologies that directly impact the construction and building sectors: thermal energy storage systems that rival traditional batteries, waste-to-value supply chains that turn industrial byproducts into low-carbon cement, and modular refining systems that recover critical metals without smelting. Each addresses a specific bottleneck in the transition toward a cleaner built environment.
Scaled Thermal Storage for Renewable Energy Integration
Renewable energy infrastructure in the United States is expanding faster than the grid can absorb it. This mismatch creates a pressing need for long-duration energy storage that can hold power for hours or days rather than minutes. Fourth Power, a spinout from MIT and Georgia Tech based in Cambridge, Massachusetts, has developed a thermal battery designed to meet this challenge. The system stores excess renewable energy as heat in an enclosure roughly the size of half a football field, with a storage capacity of up to 100 megawatts.
Liquid tin is pumped through a closed-loop graphite plumbing system and heated to temperatures reaching 2,400 degrees Celsius using electricity drawn from the grid. The superheated tin transfers its thermal energy into carbon blocks that glow white-hot and can retain heat for several weeks. When electricity is needed again, thermophotovoltaic cells convert the stored heat back into power. The round-trip efficiency is lower than that of a lithium-ion battery by up to 50 percent, but the system costs roughly one-tenth as much to produce because it is built from abundant materials such as graphite, tin, and thermophotovoltaic cells rather than lithium, cobalt, and nickel. According to CEO Arvin Ganesan, the supply chain is simple and largely circular, requiring no new mining operations. The company is developing its first demonstration unit north of Boston with a 1-megawatt capacity, built with full-sized components, and expects to launch a commercial pilot of up to 5 megawatts as a grid-connected asset by early 2026. For construction professionals, this technology matters because it enables buildings and construction projects powered by renewables to maintain consistent energy supply even when the sun is not shining or the wind is not blowing. Innovations in energy storage are becoming as critical as innovations in building materials themselves.
Waste-to-Value Supply Chains for Low-Carbon Cement
The cement industry accounts for roughly 8 percent of global carbon dioxide emissions, making it one of the hardest sectors to decarbonize. Many companies have turned to supplementary cementitious materials such as blast furnace slag from steel production and fly ash from coal plants to replace a portion of high-emitting cement clinker. This approach creates a useful circular loop: industrial waste finds a new purpose, and less carbon enters the atmosphere. But a new problem has emerged. As steel producers shift from coal-fired blast furnaces to electric arc furnaces to reduce their own emissions, the slag produced by electric arc furnaces is chemically inert and cannot be used in cement. A symbiotic relationship has been disrupted.
Carbon Upcycling, based in Calgary, Alberta, has developed a catalytic reactor that solves this problem by chemically activating inert industrial byproducts. The reactor combines diverse, locally sourced industrial waste streams and naturally occurring minerals with a source of carbon dioxide. Inside the reactor, each particle is exfoliated, increasing its surface area and allowing the COâ‚‚ to bind chemically to the particle. The resulting material can sequester carbon and serve as a feedstock for low-carbon cement production. According to CEO Apoorv Sinha, the company’s mission is to establish a waste-to-value supply chain that reduces the construction industry’s reliance on virgin materials while also cutting emissions. The company already operates a production facility in Calgary that has placed 3,000 tons of product into the market, and it is partnering with three of the twenty largest cement companies in the Western world. Future facilities are planned for Toronto, the United Kingdom, and Belgium, with each commercial plant targeting 400 to 800 tons of production per day. Understanding how material supply chains connect to climate outcomes is essential for specifiers and builders who want to make informed decisions about the products they specify.
Modular Refining for Critical Metal Recovery
The clean energy transition depends on a reliable supply of critical metals such as nickel, cobalt, copper, lithium, and rare earth elements. These materials are essential for electric vehicle batteries, energy storage systems, solar panels, wind turbines, and the electrical infrastructure that connects them. Traditional refining methods rely on smelting, which is energy-intensive and produces significant emissions, or hydrometallurgy, which generates chemical waste. Nth Cycle, a metal refining company based in Burlington, Massachusetts, has developed an alternative known as the Oyster: a 2,000-square-foot modular refining system that replaces smelting with an electro-extraction process.
The Oyster recovers production-grade metals from a variety of feedstocks including industrial scrap, end-of-life batteries, low-grade ore, and refining waste. Because the system relies on electricity rather than combustion, it can adjust seamlessly to changes in input materials and volumes. According to CEO Megan O’Connor, the circular electrochemical process achieves a 92 percent reduction in COâ‚‚ emissions compared to traditional smelting and up to 44 percent compared to existing recycling methods. The first operational Oyster is installed in a repurposed industrial facility in Fairfield, Ohio, where it produces high-value nickel products from scrap sourced from recycling companies, miners, and manufacturers. Each Oyster facility can be set up in less than twelve months and is capable of producing up to 500 tons of refined metal per year. Climate-responsive design tools help building professionals understand how the materials they choose affect the full lifecycle performance of a structure, and access to cleaner refined metals expands the palette of sustainable options.
The table below summarizes how these three technologies compare across key parameters relevant to the construction industry.
| Technology | Company | Primary Input | Key Output | Construction Relevance |
|---|---|---|---|---|
| Thermal battery | Fourth Power | Electricity, graphite, tin | Long-duration stored energy | Backup power for renewable-powered buildings |
| Catalytic reactor | Carbon Upcycling | Industrial waste, COâ‚‚ | Low-carbon cement feedstock | Reduced embodied carbon in concrete |
| Electro-extraction system | Nth Cycle | Scrap metals, battery waste | Refined nickel, cobalt, copper | Sustainable source of metals for building systems |
Bridging Innovation and Building Practice
The three startups featured in the World Economic Forum’s 2024 Technology Pioneers cohort represent different stages of the building value chain, yet they share a common thread: each one replaces a linear, extractive process with a circular, regenerative one. Fourth Power stores energy without lithium or cobalt. Carbon Upcycling turns industrial waste into construction-grade material. Nth Cycle recovers metals without smelting or toxic chemical runoff. Together, they illustrate that decarbonizing the built environment does not require a single silver bullet but rather a portfolio of complementary technologies that address energy, materials, and manufacturing simultaneously.
For architects, engineers, and contractors, the implication is that sustainable building practices are no longer limited to better insulation or more efficient HVAC systems. Sustainable innovations in construction now extend to the very supply chains that deliver energy, materials, and components to the jobsite. Specifying low-carbon concrete, choosing building materials with recycled metal content, and designing for all-electric operation backed by renewable energy are becoming practical options rather than aspirational targets. The technical infrastructure to support these choices already exists; the challenge is scaling it to meet demand.
Scaling Impact Through Material Abundance
A recurring theme across all three companies is the deliberate use of abundant, widely available materials and processes. Fourth Power builds its thermal batteries from graphite and tin rather than lithium and cobalt. Carbon Upcycling works with whatever industrial waste is locally available, avoiding the need to ship raw materials long distances. Nth Cycle designs its Oyster to accept varying feedstocks so that it can be deployed in different regions without requiring a uniform supply chain. This material-agnostic approach reduces cost, improves resilience, and makes the technologies more adaptable to local conditions, a critical advantage in global markets where material availability varies widely.
- Fourth Power’s thermal battery uses graphite and tin, both abundant and recyclable materials
- Carbon Upcycling’s reactor accepts diverse industrial byproducts, eliminating the need for a single source material
- Nth Cycle’s Oyster handles various feedstocks including scrap, low-grade ore, and battery waste
This philosophy of working with what is already available rather than extracting new resources aligns directly with circular economy principles that are gaining traction in building codes, green certification programs, and corporate sustainability commitments. Renewable energy deployment will continue to accelerate, and as it does, the technologies that pair with it must be equally scalable and sustainable.
The World Economic Forum’s Technology Pioneers program has a track record of identifying startups that go on to become household names. Alumni include companies such as Airbnb, Twitter, Kickstarter, and Google, as well as climate leaders like EcoNation and Carbon3D. The 2024 cohort suggests that the next wave of transformative companies will be those that tackle the hardest problems in energy storage, industrial waste, and material supply chains. For the construction industry, these are not abstract problems. They determine whether a building can be powered by renewable energy around the clock, whether concrete can be produced with a fraction of its current carbon footprint, and whether the metals needed for electrical systems, plumbing, and structural components can be sourced responsibly.
Each of these startups has a clear path to deployment. Fourth Power is building its first demonstration unit and targeting grid integration by 2026. Carbon Upcycling has already placed products into the market and is expanding to multiple continents. Nth Cycle is operating its first Oyster facility and proving that modular refining can compete with traditional methods on cost and performance. The construction professionals who understand these technologies today will be better positioned to specify them tomorrow. Exploring the most exciting innovations happening in the construction industry reveals that the boundaries between energy technology, materials science, and building practice are dissolving. The result is an industry that is more efficient, more resilient, and more aligned with the environmental realities of the twenty-first century.