How to Decarbonise Global Transport and Industry?

Limiting the global average temperature rise to 1.5^°C above pre-industrial levels will require decarbonisation across every sector and value chains by 2050.

This great challenge will require massive new investments and profound changes in the way industry supplies and consumes energy.

Sectors particularly hard-to-abate include road freight transport, shipping, aviation, iron and steel, and chemicals and petrochemicals, responsible for around a fifth of total CO₂ emissions.

The full decarbonisation of the hard-to-abate sectors will require a combination of approaches, given the characteristics of each sector. Yet, renewables can play a central role in the decarbonisation of all hard-to-abate sectors.

In summary, most emission reductions will have to be achieved through a combination of five main pathways which rely primarily on renewable energy and energy efficiency.

To meet decarbonisation targets under IRENA’s 1.5^°C Scenario, electrification rates must increase significantly with direct electrification technologies playing a key role.

Some available solutions are already technologically mature, for example the use of electric arc furnaces for steelmaking, which will become more important as the share of recycled steel increases in the coming decades.

Some other applications of direct electrification still need further development such as electric or hybrid aircraft and ships for short distances.

In sectors like steelmaking, chemical production, long-haul aviation and maritime shipping, direct electrification is nearly impossible. Green hydrogen and its derivatives could be key in mitigating emissions from these hard-to-decarbonise sectors.

Under IRENA’s 1.5^°C Scenario, the production of green hydrogen and its derivatives would increase from negligible levels today to almost 125 million tonnes (Mt) by 2030, and 523 Mt by 2050.

Scaling up sustainable, low-carbon bioenergy solutions is key to the decarbonisation of shipping and aviation. It is also critical in providing feedstocks for chemicals and as a potential carbon source for synthetic fuels.

Indirect electrification – i.e. via the production of renewable hydrogen – is also set to play an important role in achieving deep emissions reductions in these sectors. Examples of applications include synthetic fuels for shipping and aviation, and feedstock for chemical industries.

Sustainable aviation fuels (SAF) can reduce flight emissions by up to 80% over their lifecycle and could achieve 40-65% of sector cuts by 2050.

Fuels produced from agricultural waste, forestry residues, and solid waste represent a clean and established solution, with 30 facilities worldwide producing 8.5 billion litres of SAF in 2024.

SAF can decarbonise aviation, but reaching net‑zero by 2050 needs supportive policies such as tax incentives and subsidies to reduce costs, and increased financing for technological progress and to incentivise further adoption.

Decarbonising aluminium is critical as the sector emitted 1.1 Gt CO₂ in 2022 with demand continuing to rise.

Switching smelters to renewable electricity and increasing the uptake of low-emissions refining can enable help decarbonise most of the emissions from the aluminium sector.

A deep decarbonisation will require emerging technologies and adopting energy and material efficiency.

These require supportive policies, ongoing research and development, and systemic innovation to unlock a decarbonised aluminium sector’s benefits.

Several enabling conditions need to be put in place to accelerate the decarbonisation of hard-to-abate sectors.

These will require decisive action by governments, as well as by the private sector.

They also have fundamental implications in terms of national and international policy and regulatory environments, technology and infrastructure planning, global commodity markets, international supply chains and business models.