Cities are crucial in combating the climate crisis as they account for 70% of global CO2 emissions, primarily from fossil fuels used in industrial processes, transportation, and infrastructure. The COVID-19 pandemic showed some positive environmental effects, but the gap between current emissions and the target for net zero by 2050 is widening, especially in the buildings and construction sector.
The urgency to reverse climate crisis impacts on society, biodiversity, and the economy was highlighted at COP28, where global leaders emphasized collaborative action to limit global warming to below 1.5°C. As part of this effort, COP28 introduced the Building Breakthrough initiative, aiming for near-zero emissions and climate-resilient buildings by 2030, with 28 countries committed to this goal.
While most decarbonization efforts have focused on reducing operational emissions from buildings, it is equally important to evaluate embodied carbon, which includes emissions from manufacturing, maintenance, and decommissioning of buildings and infrastructure. This comprehensive evaluation is termed Whole Life Carbon Assessment (WLCA).
WLCA sums up the total carbon produced by a built asset throughout its life cycle, including both operational and embodied emissions. The complexity of measuring emissions associated with building materials requires reliable guidance.
The G20 Global Smart Cities Alliance and the Net-Zero Carbon Cities initiatives, in collaboration with Infosys and C40 Cities, lead a taskforce to evaluate best practices and actions concerning embodied carbon. This taskforce has released a model policy on WLCA, an Adoption Playbook for city officials, and a Practitioner’s Guide. These resources assist cities and stakeholders in developing policies for significant developments.
The policy, developed by examining existing practices in cities like London, Toronto, and Vancouver, helps governments monitor and reduce emissions in the building and construction sector. For example, Toronto has set embodied carbon caps on new city-owned buildings, Amsterdam aims for a fully circular economy by 2050, and London’s plan targets becoming a zero-carbon city.
Vincent Martinez of Architecture 2030 highlights that policies have evolved to include whole life carbon assessments, ensuring emissions throughout the life cycle of buildings are evaluated. Cécile Faraud of C40 Cities emphasizes the role of cities in driving demand for sustainable infrastructure, noting the momentum towards decarbonization and the adoption of embodied carbon policies.
In the fight against the climate crisis, cities must focus on evaluating embodied carbon to fully understand and reduce emissions. Extreme weather events, like the 2020 California wildfire, show the significant impact of climate change on safety, health, and housing. The WLCA model policy provides a foundation for standardizing practices and supporting decarbonization progress.
To make informed strategic decisions, reliable data on emissions is essential. An embodied carbon approach captures more accurate emissions data from built assets, fostering best practices. Cities like London, Toronto, and Amsterdam lead in sustainable practices, but international collective action is crucial to safeguard the planet and promote economic prosperity.
i(x) Net Zero plc (LON:IX) is an investing company which focusses on Energy Transition and Sustainability in the Built Environment, and was founded in 2015 by Trevor Neilson, Pär Lindström and Howard W. Buffett.
