From Vienna, where I live, to Dakar, New Delhi and many other cities worldwide, I’ve seen the same thing: a relentless growth in construction. New and still half-built houses, apartment blocks and other buildings — as well as bridges, roads, railways and other infrastructure — are being added daily. And their construction is causing even more warming to an already heating planet.
Steel, cement and concrete are used in most, if not all, such construction projects and have been for decades. They continue to be essential building blocks of our modern world. They also account for the largest share of industrial greenhouse gas emissions. But it doesn’t have to be this way.
To curb the climate crisis, do we need to stop building and growing? No. I believe Industrialization and urbanization can continue without worsening the climate crisis. It is a transformational opportunity — although it requires new technology, more transparency and a political transformation of its own.
Producing steel and cement (also used to make concrete) requires continuous high-temperature heat and huge amounts of energy, much of which is still dependent on fossil fuels, as well as carbon-intensive chemical processes.
To support more climate-friendly electrification of these industrial heat processes, new technologies need to emerge but also be commercialized and brought to scale. They need to be as accessible and affordable as possible — as soon as possible.
New levels of transparency are needed to track progress towards greener construction. Embodied carbon emissions — meaning those from the full lifecycle from the extraction, production, delivery and use of materials — need to be regularly, systematically monitored and disclosed. And the data should be comparable across projects.
Capturing the full picture is crucial. We need low-carbon construction materials to become the norm — but we also need building designs that reduce energy consumption and city planning to promote carbon-removing green spaces. To achieve all of this, we need better data to guide and evaluate decisions.
Governments — major purchasers of construction materials and funders of infrastructure projects — need to align their procurement practices with their climate goals. To do this, they also need to be able to evaluate proposals for specific projects and specific materials, based on their expected carbon footprints, instead of just on cost.
National, regional and local governments and agencies account for 20 to 30 percent of total construction industry revenues, and 40 to 60 percent of concrete sales for example. Their policies can stimulate the innovation and dissemination of promising technologies.
Incentives, including promises from governments to buy and use less carbon-intensive construction materials, can help speed up progress. Companies that take the lead in using and creating greener processes should also be rewarded. These key understandings are behind the new Green Public Procurement Pledge.
Announced at September’s Global Clean Energy Action Forum in Pittsburgh, this pledge calls on governments to cut carbon from their publicly funded construction projects. It includes several "ambition levels" including targets to use low emission materials in all such projects, and near-zero materials in flagship projects by 2030.
Some companies are meanwhile racing to install the first commercial-scale facilities for greener steel and cement, and to implement new carbon capture technologies.
The long-term goal is net-zero construction by 2050, but to achieve that we need interim action. The pledge builds on announcements supporting green procurement that were made at the UN climate change conference COP26 last year. Repetition in this case is important: industries and innovators need to hear often, from many sources, that there is a serious and increasing demand for greener materials.
The pledge also explicitly recognizes that buying near-zero construction materials may come at a premium cost. This is an important and strong signal to the market: If you make it, we will buy it (even if it costs more in the short-term).
Governments involved in the international Industrial Deep Decarbonization Initiative (IDDI) which released the pledge include Canada, Germany, India, and the United Kingdom — as well as the United States and Saudi Arabia which announced joining in Pittsburgh. We need to see more governments come on board and make their own specific commitments following local consultations in their countries.
Some companies are meanwhile racing to install the first commercial-scale facilities for greener steel and cement, and to implement new carbon capture technologies. But we need even more to join them, to actually meet our climate goals.
Helpfully, there are other transformative experiences that we can learn from here. Take solar energy. This technology used to be very expensive — until countries committed to renewable energy targets and after some, such as the United Arab Emirates, built large-scale solar plants with transparent tenders and contracting processes that helped to dramatically drive down the cost. Similar strategies and impacts are needed in the global construction industry and for its basic materials.
Globally, many countries are still industrializing and urbanizing. The world is expected to build the equivalent of another New York City every month for the next 40 years. Decarbonizing construction is thus an unavoidable imperative. The size of the challenge is vast, and current efforts are not enough to respond to it.
The good news is that greener construction is not a fantasy. It may take many years for this to become widespread, and work already begun must accelerate. Governments and industries must come together, reinforce each others’ messages, work together more synergistically and move in the same direction.