Embodied carbon dioxide emissions to provide high access levels to basic infrastructure around the world

Abstract

Access to infrastructure services is essential to meet human basic needs. However, infrastructure construction requires carbon-intensive materials, first and foremost cement and steel. In this paper, I assess if high level of access to 5 basic infrastructure services – electricity, water, shelter, sanitation and transportation – can be provided at the global scale in 2030 and until 2050 without compromising climate mitigation targets. Following historical patterns, I first quantify the cement and steel requirements in each country associated with providing high access levels. I then estimate the production-based carbon dioxide emissions related to manufacturing the cement and steel needs. To do so, I model influencing factors such as national production technologies mix, trade structure and mitigation actions in the cement and steel industries. Global cumulative material demand (central values) to reach high access level in 2030 is the lowest for water with 8 Gt of cement and 1 Gt of steel and the highest for transportation with 50 Gt of cement and 6 Gt of steel. Most of the cement and steel demand is concentrated in Asia, Middle-East and Africa. I show for all infrastructure services that achieving high access level in 2030 and until 2050 induces cumulative carbon dioxide emissions well below the carbon budgets related to Paris Agreement targets, with central values under baseline scenario from 10 to 53 Gt CO2 depending on the infrastructure service. However, I find providing high sanitation and transportation access in Middle-East and Africa conflicts with existing low-carbon pathways. This calls for on one side implementing material efficiency and substitution towards less carbon-intensive construction materials, and on the other side strengthening mitigation efforts in wealthiest countries to leave enough ’carbon space’ for basic infrastructure development in emerging countries.