Landmark report: How the world could decarbonise energy by 2050

A landmark report has mapped out how the world could have a zero-emissions energy sector by 2050. Photo / Christopher Furlong/Getty Images

A landmark report has mapped out how the world could have a zero-emissions energy sector by 2050 - starting with a halt on new fossil fuel projects and an "immediate and massive" surge in clean tech.

A Kiwi climate campaigner has described the International Energy Agency's just-released report a "tremendous win" for advocates who have long demanded the major organisation push toward limiting global warming to 1.5C above pre-industrial levels.

The report marked the world's first comprehensive study of how to transition to a net zero energy system by 2050, all while ensuring stable and affordable energy supplies, providing universal energy access, and enabling economic growth.

It set out a cost-effective and economically productive pathway, resulting in a clean, dynamic and resilient energy economy dominated by renewables like solar and wind instead of fossil fuels.

The report also examined key uncertainties, such as the roles of bioenergy, carbon capture and behavioural changes in reaching net zero.

"Our roadmap shows the priority actions that are needed today to ensure the opportunity of net-zero emissions by 2050 – narrow but still achievable – is not lost," said the IEA's executive director, Fatih Birol.

"The scale and speed of the efforts demanded by this critical and formidable goal – our best chance of tackling climate change and limiting global warming to 1.5C – make this perhaps the greatest challenge humankind has ever faced."

The report set out more than 400 milestones to decarbonise energy by 2050.

That included halting any further investment in new fossil fuel supply projects, and no further final investment decisions for new unabated coal plants.

By 2035, there'd be no sales of new internal combustion engine passenger cars, and by 2040, the global electricity sector would have already reached net-zero emissions.

In the near term, the report described a net zero pathway that requires the immediate and massive deployment of all available clean and efficient energy technologies, combined with a major global push to accelerate innovation.

The pathway called for annual additions of solar PV to reach 630 gigawatts by 2030, and those of wind power to reach 390 gigawatts.

Together, this was four times the record level set in 2020.

For solar PV, it was equivalent to installing the world's current largest solar park roughly every day.

A major worldwide push to increase energy efficiency was also an essential part of these efforts, resulting in the global rate of energy efficiency improvements averaging four per cent a year through 2030 – about three times the average over the last two decades.

Most of the global reductions in CO2 emissions between now and 2030 in the net zero pathway come from technologies readily available today.

But in 2050, almost half the reductions come from technologies that were currently only at the demonstration or prototype phase.

This demanded that governments quickly increase and reprioritise their spending on research and development – as well as on demonstrating and deploying clean energy technologies – putting them at the core of energy and climate policy.

Providing electricity to around 785 million people who have no access to it and clean cooking solutions to 2.6 billion people who lack them is an integral part of the pathway.

This would cost around $40b a year, or equal to around one per cent of average annual energy sector investment.

Under the IEA's pathway, solar would serve as the world's single largest source of total energy supply by 2050. Photo / Supplied

The pathway also assumed total annual energy investment surges to USD $5 trillion by 2030 in the net zero pathway, adding an extra 0.4 percentage points a year to global GDP growth.

The jump in private and government spending creates millions of jobs in clean energy, including energy efficiency, as well as in the engineering, manufacturing and construction industries.

By 2050, the energy world would look completely different, with global demand around 8 per cent smaller than today, but serving an economy more than twice as big and a population with two billion more people.

Almost 90 per cent of electricity generation would come from renewable sources, with wind and solar PV together accounting for almost 70 per cent, and the remainder from nuclear power.

Solar would serve as the world's single largest source of total energy supply, while fossil fuels would fall from almost four-fifths of total energy supply today to slightly over one-fifth.

Fossil fuels that remained would be used in goods where the carbon is embodied in the product such as plastics, in facilities fitted with carbon capture, and in sectors where low-emissions technology options were scarce.

"The pathway laid out in our roadmap is global in scope, but each country will need to design its own strategy, taking into account its own specific circumstances," Birol said.

The report comes as New Zealand's Climate Change Commission is soon due to deliver its final advice to the Government on how the country could make its commitments compatible with the global reach toward 1.5C.

Its draft recommendations included winding down imports of petrol and diesel cars by 2032, closing the Tiwai Point Aluminium Smelter, switching industrial heating sources to electricity and biomass, and ensuring at least 60 per cent of our energy was renewable by the end of 2035.

Kiwi climate campaigner David Tong has described the International Energy Agency's just-released report a "tremendous win" for advocates. Photo / Dean Purcell

David Tong, a New Zealand-based campaigner with the group Oil Change International, hailed the IEA's report.

"While we applaud the IEA for taking this step, they can rest assured that advocates will continue pushing for the institution to complete the job," he said.

"The IEA needs to fix the flaws in this report by prioritising truly clean technologies, and thrust that fixed scenario into the center of the 2021 World Energy Outlook.

"By continuing to underestimate wind and solar potential, the IEA is still encouraging dangerous levels of reliance on carbon capture and storage, fossil gas, and bioenergy, technologies favoured by polluting industries but harmful for people."

Tong said that, instead of banking on polluting technology, the IEA should be accelerating the phase-out of fossil gas and coal by relying on proven wind and solar solutions.

"We need the IEA to be a beacon pointing the way to a truly clean, Paris-aligned future," he said.

"With today's report, that light is starting to appear, but it is not yet shining as bright as it must."