Transition Pathways for Sustainable Infrastructure

Decarbonisation and beyond – What is the future of infrastructure?

As the world faces widespread climate, energy, and economic crises, the development of sustainable infrastructure can massively accelerate the achievement of climate and sustainable development goals (SDGs), while creating strong and resilient economies.

Between 2020 and 2030, G20 economies will invest USD11.5 trillion in infrastructure that is aligned to the climate transition and SDGs. This GI Hub initiative on Transition Pathways for Sustainable Infrastructure is helping governments shape future infrastructure to meet global climate targets and the SDGs with practical, accessible research and open consultations. 

G20 long-term infrastructure investment between 2015 and 2070

Note: Based on G20 infrastructure plans published between January 2010 and June 2022. Data are likely to change as the market evolves. This work is a ‘living’ resource that will evolve with progress toward the climate goals and SDGs.

Our research began with 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 analysis, we distilled 15 broad actions – or transition pathways – that must be taken for infrastructure development and delivery to advance achievement of climate targets and SDGs.

Now, we’re releasing this work for use by governments and industry, while continuing to progress our research in consultation with stakeholders.

What you will find here

The current state, and where we need to go

Greenhouse gas emissions from infrastructure must be addressed to transition to a low-carbon economy

The urgency of the climate crisis is driving a renewed focus on infrastructure development and infrastructure investment. Infrastructure could contribute more than any other sector to the transition to net zero and a low-carbon economy, given that the infrastructure industry is the leading emitter of greenhouse gases. Infrastructure is responsible for more than 79% of global greenhouse gases and consumes 60% of the world’s materials.

Infrastructure influences achievement of all 17 UN Sustainable Development Goals and up to 92% of all SDG targets

Analysis by UNOPS found infrastructure influences all 17 SDGs, and has the ability to impact up to 92% of all SDG targets. Sustainable infrastructure is defined as infrastructure that fits the broad definition of sustainability framed by the SDGs of 'meeting the needs of the present without compromising the ability of future generations to meet their own needs’. It goes hand-in-hand with the transition to a low-carbon economy and the achievement of climate targets like those of the Paris Agreement.  

How do we get there? Infrastructure transition pathways are the broad actions that will create sustainable and climate-resilient infrastructure

Through a large-scale research effort that examined global approaches to the climate transition and decarbonisation of infrastructure on behalf of the G20, the GI Hub has identified 15 transition pathways. These pathways are actions that align infrastructure development and delivery with global climate targets and SDGs.

From a climate perspective, the pathways address both mitigation (to reduce GHG emissions) and adaptation (to increase the resilience of infrastructure to the impacts of climate change). This is important given that much less investment is being directed to adaptation, and this is true across almost all infrastructure sectors.

The pathways look beyond decarbonisation to encompass all infrastructure sectors and subsectors, across all stages of the infrastructure lifecycle. We expect the transition pathways to advance and evolve as the climate transition accelerates, governments and industry develop more technological solutions, and infrastructure becomes more digitalised.

Currently, a major barrier to implementing the pathways is the shortfall of investment in sustainable infrastructure: the ‘sustainable infrastructure investment gap’. Roughly USD2.6 trillion is required annually through 2030 to meet the SDGs and stay on a path to reach net zero by 2050. That’s why our research also identifies effective and innovative mechanisms to finance low-carbon infrastructure and the climate transition.

The 15 transition pathways

The transition pathways below can be used by governments and industry to systematically plan infrastructure development and investment to achieve climate targets and the SDGs.

Infrastructure transition pathways for climate mitigation

Transition pathway Definitions and outcomes Sectors

Increase the share of renewable energy

Increasing renewable energy generation and decarbonising power consumption

Transformative outcomes: Low-carbon transition; pollution reduction; job creation and economic growth

Renewable energy Energy, storage, transmission, and distribution Transport Social Waste Water Communications Other

Increase the share of low-emissions vehicles

Increasing the uptake of low-emissions vehicles to reduce fossil fuel combustion and tailpipe emissions

Transformative outcomes: Low-carbon transition; pollution reduction; job creation and economic growth

Transport Renewable energy Energy, storage, transmission, and distribution

Increase technological carbon removal

Deploying carbon-capture technology to capture and store or re-use carbon dioxide emitted from large-point sources

Transformative outcomes: Low-carbon transition; pollution reduction; job creation and economic growth

Non-renewable energy Other

Replace coal in power generation with low carbon non-renewables

Reducing coal-fired power generation from the energy mix and replacing it with transition fuels such as oil, gas, and nuclear to reduce the energy sector’s emissions intensity

Transformative outcomes: Low-carbon transition; pollution reduction; job creation and economic growth

Non-renewable energy Energy, storage, transmission, and distribution Other

Increase the operational efficiency of buildings

Retrofitting, modernising, and sustainably operating buildings to optimise and reduce water and energy use

Transformative outcomes: Low-carbon transition; pollution reduction; digital connectivity; job creation and economic growth

Social Renewable energy Energy, storage, transmission, and distribution Communications Other

Reduce the carbon intensity of steel and cement production

Using renewable energy, low-emissions fuels, or other mitigation measures to reduce the embodied carbon of steel and cement

Transformative outcomes: Low-carbon transition; pollution reduction; job creation and economic growth

Renewable energy Non-renewable energy Energy, storage, transmission, and distribution Other
Increase the share of renewable energy
Increase the share of low-emissions vehicles
Increase technological carbon removal
Replace coal in power generation with low carbon non-renewables
Increase the operational efficiency of buildings
Reduce the carbon intensity of steel and cement production

Infrastructure transition pathways for climate adaptation

Transition pathway Definitions and outcomes Sectors

Increase resilience through structural interventions

Building new structures, or changing the structure of existing infrastructure, to protect communities and the infrastructure itself against shocks and stresses

Transformative outcomes: Disaster and climate change adaptation; social cohesion; job creation and economic growth

Water Social Renewable energy Non-renewable energy Energy, storage, transmission, and distribution Transport Waste Communications Other

Increase resilience through ongoing risk management

Actively managing, maintaining, and monitoring infrastructure to (a) reduce the risk of failure and (b) improve its ability to respond to, and recover from, shocks and stresses

Transformative outcomes: Disaster and climate change adaptation; social cohesion; job creation and economic growth

Water Social Renewable energy Non-renewable energy Energy, storage, transmission, and distribution Transport Waste Communications Other

Restore land and water ecosystems

Implementing nature-based solutions to restore and protect ecosystems in response to challenges such as climate change

Transformative outcomes:  Disaster and climate change adaptation; environmental regeneration; social cohesion; job creation and economic growth

Water Social Waste Other
Increase resilience through structural interventions
Increase resilience through ongoing risk management
Restore land and water ecosystems

Infrastructure transition pathways that deliver social outcomes/impacts

Transition pathway Definitions and outcomes Sectors

Increase universal access to infrastructure

Removing obstacles and barriers to infrastructure and infrastructure services to increase connectivity and inclusivity across communities

Transformative outcomes: Affordability and access to services; job creation and economic growth; digital connectivity; digitalisation; social cohesion; disruptive innovation; inclusive mobility

Communications Energy, storage, transmission, and distribution Non-renewable energy Renewable energy Social Transport Waste Water Other

Increase the affordability of infrastructure services

Introducing policies and incentives to support the cost of infrastructure services

Transformative outcomes: Affordability and access to services; job creation and economic growth; digital connectivity; digitalisation; inclusive mobility

Transport Water Energy, storage, transmission, and distribution Non-renewable energy Renewable energy Social Communications Waste Water

Improve the standard of operation of infrastructure

Upgrading and maintaining infrastructure to improve the standard of operation of infrastructure

Transformative outcomes: Circularity; cyber-security; digital connectivity; digitalisation; pollution reduction; disaster and climate adaptation; social cohesion; disruptive innovation; job creation and economic growth; low-carbon transition

Transport Energy, storage, transmission, and distribution Non-renewable energy Renewable energy Social Communications Waste Other
Increase universal access to infrastructure
Increase the affordability of infrastructure services
Improve the standard of operation of infrastructure

Infrastructure transition pathways that amplify the other pathways

Transition pathway Definitions and outcomes Sectors

Scale up the adoption of InfraTech

Applying new or innovative technology (material, machine, or digital) across the project lifecycle to create a step-change in mitigation, adaptation, or social outcomes

Transformative outcomes: Disruptive innovation; digitalisation; low-carbon transition; pollution reduction; disaster and climate adaptation; social cohesion; job creation and economic growth

Transport Social Renewable energy Energy, storage, transmission, and distribution Water Waste Communications Other

Increase the digitalisation of services

Digitising infrastructure and related government services to improve connectivity, efficiency, and quality of service

Transformative outcomes: Digitalisation; digital connectivity; disruptive innovation; job creation and economic growth

Communications Social Transport Water Other

Increase circularity and minimise raw material use

Re-using, recycling, and recovering waste streams to minimise the use of materials across the infrastructure lifecycle

Transformative outcomes: Circularity; environmental regeneration; pollution reduction; job creation and economic growth

Waste Water Other
Scale up the adoption of InfraTech
Increase the digitalisation of services
Increase circularity and minimise raw material use

Transition pathways and the G20 infrastructure agenda

The GI Hub’s work on infrastructure transition pathways began in 2022 in response to a request by the G20 Infrastructure Working Group (IWG), under the Indonesian G20 Presidency. The IWG asked the GI Hub to examine trends associated with the transition of infrastructure to achieve global climate targets and SDGs. We incorporated feedback from G20 members into our ongoing work on the infrastructure transition pathways, and this will include the government consultations and ongoing analyses we are currently undertaking. This work complements our InfraTracker, which tracks budgeted public investment in infrastructure in G20 economies and draws on the research we conducted on Transformative Outcomes through Infrastructure.