Using a scenario approach to reshape the debate on global infrastructure investment needs

Organizers: Julie Rozenberg, Marianne Fay (World Bank)


The infrastructure gap is large – 1.2 billion individuals are without electricity, 663 million lack improved drinking water sources, 1 billion live more than 2 km from an all-weather road – and the solution, many argue, is to spend more. But the story is not so simple.  How much is needed depends on the objective pursued, which lies with individual countries’ contexts, economic growth aspirations, and social and environmental objectives.

There is a need to shift the investment needs debate away from a simple focus on spending more, towards spending better on the right objectives using relevant metrics. For this, scenario exercises are particularly relevant. They help clearly defining the (multiple) goals of infrastructure investments, as well as the sensitivity of the results to assumptions—about pricing, technology, demand, climate change and climate policy, and other key factors in ways that can help inform policy choices.  

There is a need for infrastructure investment costs estimates structured in an “if-then” framework (if this is what is wanted and these are the assumptions made, then this is how much it would cost). Infrastructure costs in water, energy, transport, and flood protection, could be explored as pathways towards multiple SDGs. To identify the most relevant objectives and assumptions for this “if-then” approach in each sector, hundreds of scenarios can be explored, and the “cost drivers” – that is, the decisions and assumptions that best explain the spread in infrastructure costs – can be highlighted. 

Such scenario exercises can help identify climate change mitigation and adaptation pathways that require relatively low infrastructure investments, and the complementary policies that need to be in place to ensure investments are timely and the infrastructure is used efficiently.

This session will have one invited speaker focused on investment needs for improving access to basic infrastructure services. In addition, the session welcomes submissions (speakers and posters) on work that develops or applies scenario-based methods to investigate infrastructure issues at the local to global scale, including investment needs, sensitivity to determinants, or relation to SDGs or to mitigation/adaptation strategies.