Decarbonizing Construction: Strategies for a Sustainable Industry

Summary

The construction industry is one of the largest and most indispensable market sectors for global development, accounting for 14.2% of global GDP and employing over 10 million individuals in the United States alone. Yet the industry is also one of the heaviest polluters in the world, producing 40% of total global carbon emissions. However, despite growing awareness among industry leaders of the need to decarbonize, the process is much easier said than done.

To rectify this, the industry as a whole must undergo a transformation toward becoming net-zero. The challenges will be immense and the expense will be considerable, but given the mounting pressure from regulatory bodies and public sentiment for the industry to clean up its act, the race is on to make construction more eco-friendly.

Embodied carbon: The biggest problem

When discussing carbon emissions in construction, we need to consider two types. First, there is operational carbon–the ongoing emissions released from maintaining a building's heating, cooling, ventilation, lighting and power systems. The second type is embodied carbon, which comprises all of the emissions released during the extraction and manufacturing processes to create building materials. While building owners can actively reduce operational emissions over time by switching to sustainable energy sources, the embodied carbon emissions, which are generated during the production and construction phases, remain a fixed impact unchangeable after the completion of the building project.
 
This means that extraction and manufacturing processes need to change. Fortunately, recent years have seen significant advances in Carbon Capture, Utilization and Storage (CCUS) solutions offering effective ways to reduce buildings’ embodied emissions. One key approach is point-source capture, a method that targets and captures CO2 emissions directly at their industrial source, such as in factories producing high-CO2 materials like cement and steel.
 
Other innovative approaches include Direct Air Capture (DAC) and Direct Ocean Capture (DOC). Once captured, CO2 can then be transported to a new site to be converted into clean fuels or products, known as Carbon Capture and Utilization (CCU), or be stored underground in geological formations, known as Carbon Capture and Storage (CCS).
 
Both CCU and CCS provide promising pathways toward a cleaner, more efficient and sustainable construction industry. However, most CCU and CCS development is still taking place at the startup level. One example is Canadian startup Carbon Upcycling, which converts CO2 waste into additives for various industries like plastics, coatings, cement, concrete and more. Other startups are exploring their own carbon valorization methods with the end goal of creating a range of cost-effective and scalable methods for reducing carbon emissions at every stage of the construction value chain.
 
To get there, though, large corporate players will need to step in, not only through investments in these startups but also by adopting their technologies. Because, ultimately, investments only help a startup get to the adoption phase. To ensure the industry’s decarbonization, large-scale adoption is also necessary. In this context, governments, policy makers and industry leaders will play a pivotal role in creating investment-friendly environments. This means offering useful grants and creating sustainability initiatives that drive further investment, adoption and innovation among industry stakeholders.

Moving to a circular economy

Among the other initiatives that the construction industry must embrace, one of the most crucial is the concept of a circular economy, a system focused on minimizing waste and extending the life of resources. This approach is crucial to ensuring proper management and reuse of waste debris from construction and demolition projects.
 
Any time a building is constructed or demolished, significant amounts of construction, demolition and excavation waste (CDEW) are generated. Most of this waste–a diverse mix of concrete, wood, metals and other materials–usually ends up in landfills, where it poses environmental risks. But if demolition companies could properly separate and catalog CDEW, materials could be repurposed and given a new life in other stages of the construction value chain.
 
Numerous startups are currently pioneering approaches in this realm. For example, Soil Connect is an innovative digital marketplace that provides a better, faster and cheaper way to connect those with soil, aggregates and building materials with those who need it. Another noteworthy example is WtEnergy, a Spanish startup converting biomass and non-recyclable waste into a lower-carbon energy solution, which can be used in the short term as a fossil fuel alternative or be upgraded in the medium and long term to gasses such as biomethane or pure hydrogen. These examples offer just a snapshot of the diverse strategies adopted by many startups to support a circular economy.
 
While establishing a circular economy business model may incur higher initial costs compared to traditional methods, we need to measure those costs against the long-term benefits. For instance, lessening the demand for finite natural resources can result in significant savings, particularly amid the current price surges for almost every type of building material. There’s also the regulatory aspect. As more governments continue to impose stricter regulations and penalties for unsustainable practices, investing in a more sustainable business model becomes a strategic and prudent choice.

Embracing green energy alternatives

Across the world, almost every major industry is under pressure to move away from traditional fossil fuel power and embrace greener energy alternatives. While this transition is essential to avoiding irreparable damage from climate change, it poses a particular challenge for an industry like construction in which 98% of all energy comes from diesel. Fortunately, advances in green energy development have yielded a range of green alternatives. In particular, hydrogen energy and sustainable industrial heat production stand out as the most promising for the construction industry.
 
When hydrogen is manufactured through the use of renewable energy sources, the result is a clean, zero CO2 emission carbon energy source. Despite the current dominance of fossil fuels globally, efforts are underway to expand the production and market viability of zero-emission  hydrogen. Given enough time and investment, it’s reasonable to expect that clean hydrogen will become a major power source for construction.
 
The same can be said for sustainable industrial heat. Traditionally, the construction industry has relied on fossil fuels to power the technologies that produce the high temperatures required to run industrial processes. But if those feedstocks were replaced with energy from renewable sources like solar, geothermal and biofuels, the result would be a significant decarbonization of industrial heat production. Presently, many startups are involved in various approaches to generating sustainable industrial heat that have high applications for the production of cement, steel, iron and chemicals.
 
The main challenge now lies with scaling these technologies for widespread adoption. Again, boosting collaboration and investment with startups that are either directly involved in (i.e., Contech) or adjacent to (i.e., Cleantech, Climatetech) the construction industry will be essential for advancing a clean energy transition.

Final thoughts

For the global construction industry, decarbonization is going to present some major challenges. Massive changes will be necessary at every level, from infrastructure and supply chains to adopting new technologies and industrial processes. To ensure decarbonization, however, greater collaboration will be needed between leading industry corporations, startups and regulatory bodies. By taking the first steps now, the construction industry can lay the foundation for a sustainable, efficient and carbon-neutral future.