Renewable energy boom may help us limit warming this century to 1.5 ̊C

The unprecedented growth of the renewable energy and electric vehicle sectors over the past two years has kept a path open to limiting global warming below 1.5 ̊C this century. But the path is narrowing, according to a report from the International Energy Agency (IEA).

“Keeping alive the goal of limiting global warming to 1.5 ̊C requires the world to come together quickly,” said IEA director Fatih Birol in a statement. “The good news is we know what we need to do – and how to do it.”

The report updates the organisation’s 2021 roadmap laying out how the global energy system would have to change to reach net-zero emissions by 2050. That evaluation found that if countries around the world adopted the cuts described in the roadmap, global average temperatures would temporarily rise above 1.5 ̊C compared to pre-industrial levels, then fall below that threshold by the end of the century.

The updated report finds that despite the continuing rise in global greenhouse gas emissions, a clean energy boom since 2021 has kept the pathway in sight – if only just.

In the 2021 report, half of projected emissions cuts were achieved by technologies that weren’t yet available. In the new report, that drops to 35 per cent, with technologies like carbon capture, hydrogen and bioenergy playing less of a role, and with renewables and improved energy efficiency doing more.

This reflects record increases in solar power and electric vehicle adoption over the past two years – both of which are in line with the steep trajectories required to reach global net-zero emissions by mid-century, the report finds. Based on this shift, the IEA forecasted for the first time that fossil fuel demand will peak before 2030.

The updated report also reflects major changes to the global energy system since 2021, including new policies emphasising energy security following Russia’s invasion of Ukraine.

“The pathway to 1.5 ̊C has narrowed in the past two years, but clean energy technologies are keeping it open,” said Birol. He pointed to signs of international momentum moving away from fossil fuels and towards sustainable energy sources, such as a recent agreement by the G20 intergovernmental forum to triple renewables by 2030.

Despite those encouraging signs, the amount of greenhouse gases already released into the atmosphere means the Paris Agreement target of avoiding any overshoot of 1.5 ̊C is almost certainly out of reach, regardless of future emissions, says Michelle Dvorak at the University of Washington.

Even meeting the less ambitious target of keeping warming below 1.5 ̊C by the end of the century would require more ambitious policies. The IEA report says high-income countries would have to move their net-zero targets earlier to 2045, and China would need to achieve net zero by 2050, rather than 2060. Emerging economies would have more time.

Cutting the required emissions would still remain extremely challenging. The report finds closing the gap would also necessitate doubling the rate of system-wide energy efficiency improvements and steeply increasing already unprecedented sales of electric vehicles and electric heat pumps.

The fossil fuel industry would also need slash methane emissions by 75 per cent, and around 2 million kilometres of transmission lines would have to be built each year from now to 2030 to get all the clean electricity to where it is needed.