As the backbone of economies, infrastructure enables societies to function and thrive. However, the effects of climate change have amplified infrastructure’s existing vulnerabilities and created new ones, threatening communities, economies, and ecosystems across the world. Accounting for 79% of total greenhouse gas emissions and 88% of adaptation costs, infrastructure plays a pivotal role in influencing net zero targets and the majority of the UN’s Sustainable development Goals (SDGs).
Between 2020 and 2030, G20 national governments plan to invest around USD12.4 trillion into infrastructure – around 1.3% of the G20’s GDP annually. For the world to reduce greenhouse gas emissions, build resilience to extreme climate conditions, and secure long-term sustainable development, it is imperative that these investments align with transition pathways.
Why are transition pathways for sustainable infrastructure important?
Currently, a major barrier to implementing sustainable infrastructure is the shortfall in investment. To support economic growth and meet climate targets and SDGs, it is estimated that the sustainable infrastructure investment gap is around USD3 trillion per year (as a point of reference, G20 national governments budgeted just under USD1 trillion for infrastructure in 2022).
This gap cannot be bridged through public financing alone. There will be a need to scale up private sector investment in infrastructure for the foreseeable future. To do this, investors need clear national infrastructure plans to understand how governments intend to achieve those goals.
To address this opportunity, the GI Hub examined transition pathways for sustainable infrastructure that link long-term sustainability goals with infrastructure plans.
What are the transition pathways?
Through a large-scale research effort that examined global approaches to the climate transition, the GI Hub identified 15 transition pathways. Our research involved an analysis of more than 250 long-term national infrastructure plans of 25 G20 economies to extract policy and investment data that were mapped to climate targets and SDGs. From this, we distilled 15 broad actions – transition pathways – that must be taken for infrastructure development and delivery to advance the achievement of climate targets and SDGs.
The 15 transition pathways can be categorised into four key objectives:
- Climate mitigation: Including pathways for increasing the share of renewable energy and low-emission vehicles, increasing the operational efficiency of buildings, and reducing the carbon intensity of steel and cement
- Climate adaptation: Including pathways for increasing resilience through structural interventions and ongoing risk management, and restoring land and water ecosystems
- Social outcomes / impacts: Including pathways for increasing universal access and affordability, and improving the standard of operation of infrastructure
- Pathway amplifiers: Including scaling up the adoption of InfraTech, increasing digitalisation, and increasing circularity to minimise raw material usage.
The breakdown in how the G20 planned investments were mapped to the 15 transition pathways are shown in the chart below.
Investment trends by transition pathway, expressed as the average percentage of a country's GDP.
Examples of transition pathways
Decarbonising transport
Transport infrastructure is critical to increasing positive economic and social outcomes in both emerging and advanced economies, so improving the speed, efficiency, quality, and availability of transport is a priority. G20 central governments are investing heavily in the transport sector, which was 42% of G20 governments’ total investment in infrastructure in 2022. The construction, operation, and maintenance of transport infrastructure (especially in roads) is also one of the highest emitters of CO2 globally. Investing in decarbonising transport is therefore a priority.
Decarbonising transport has the second-highest level of representation in national infrastructure plans, with 17 G20 economies committed to decarbonising transport. By contrast, 22 G20 economies are committed to decarbonising energy, eight to decarbonising social infrastructure, and only one to decarbonising water.
What does it mean to decarbonise transport?
The chart below shows the sub-sector investments for decarbonising / mitigating CO2 emissions from transport (blue bar), compared with the overall sub-sector investment (grey bar). Investments in rail and road transport are the highest overall investment trends on average, however the decarbonisation components of these investments are relatively low (around 12% of total investment for rail and 16% for road). Other opportunities to decarbonise transport include investing in alternative fuel production, decarbonising air and public transport modes, and reducing reliance on motorised vehicles by increasing the adoption of active and shared mobility.
Planned investment by transport sub-sector
Scaling up InfraTech
InfraTech has the potential to accelerate the climate transition and SDGs by enhancing the cost efficiency, affordability, and transformative impact of sustainable infrastructure. Maximising infrastructure’s ‘bang for buck’ through the use of InfraTech is especially important in light of the sustainable infrastructure investment gap. InfraTech also plays an important role in increasing private investment in infrastructure, by providing analyses and data that investors can use to better understand risks and costs. However, the International Energy Agency (IEA) estimates that almost 35% of the cumulative CO2 emissions reductions projected for 2070 will come from technologies that are currently at the prototype or demonstration phase, and will not become available at scale without further investment into R&D and commercial demonstrations.
Scaling up the adoption of InfraTech is considered a pathway amplifier that cuts across all transition pathways and sectors. Our data indicate that the highest and the most representative InfraTech trends by far across the G20 are in road transport, with a large emphasis on electric vehicle investments. This is seen in the chart below which shows InfraTech-related investments (in green) compared with the overall investment (in grey). The adjacent chart on the right indicates the level of representation across the G20, showing the number of economies with InfraTech-related investments in their plans.
Left: Planned investment by asset (road transport) – ‘Scale up the adoption of InfraTech’. Right: G20 economies with InfraTech investment
Examples of InfraTech solutions to make roads more sustainable include advanced technologies to detect landslides, low-carbon maintenance, satellite-based condition monitoring, hazard monitoring using artificial intelligence, and innovative soil stabilisation.
InfraTech also plays an important role in increasing private investment in infrastructure, by providing analyses and data that investors can use to better understand risks and costs. However, 40% of new technologies required to achieve emission reduction targets are still under development, so investment in new solutions is also critical.
Progressing the infrastructure transition agenda
In the race to mitigate climate change, infrastructure stands as both a challenge and an opportunity. The transformation of infrastructure offers us a chance to mitigate emissions, enhance resilience, and create a sustainable future. Decisions that are made today in the design and development infrastructure will shape the trajectory of societies for generations to come. By prioritising climate-resilient infrastructure, we can not only mitigate the impacts of climate change, but also pave the way for a more sustainable and equitable world.
The GI Hub is leading the transformation of infrastructure through our Transition Pathways initiative. View all 15 transition pathways here.
Transformative Outcomes Through Infrastructure
