Phasing down, phasing out, or transitioning away: What did COP28 agree on fossil fuels?

This article was first published on 21 November 2023 and was updated on 13 December 2023.

The COP28 summit in the United Arab Emirates ended with nations from nearly 200 countries agreeing to reduce consumption of fossil fuels.

The deal states an intention to "transition away from fossil fuels in energy systems, in a just, orderly and equitable manner ... so as to achieve net zero by 2050 in keeping with the science".

It is the first time a global climate change meeting - or COP - deal has called for a reduction in fossil fuel use. But the deal did not include any specific language on whether we should "phase down" or "phase out" fossil fuels, which had been a key debate in the run-up to COP28.

Here are the arguments for phasing out and phasing down fossil fuels, and why it matters for the planet.

There are eight key reasons to phase out fossil fuels, according to environmental group Greenpeace.

These are – as you might expect – mostly related to the fact that oil, coal and gas are contributing to climate change.

“We need to take transformative action in the next decade to completely phase out fossil fuel production and transition our economy to 100% renewable energy,” Greenpeace says. “Every new ton of greenhouse gas emissions pushes global temperatures closer to the 1.5°C limit.”

Many businesses support this position.

The We Mean Business Coalition, a non-profit that supports businsses to take climate action, said, ahead of COP28: "200+ companies representing over $1.5 trillion in global annual revenue are urging national governments to address the primary cause of climate change: burning fossil fuels."

“Our businesses are feeling the impacts and cost of increasing extreme weather events resulting from climate change,” it said. “The transition to net zero could boost global GDP by 4% by 2030.”

The G7 agreed to accelerate a phase-out of fossil fuels earlier this year. However, it included the word “unabated” in this promise, meaning that the effort would not apply to fossil fuel used alongside carbon capture technology.

The main argument for slowly phasing down rather than completely phasing out fossil fuels is that the world needs these energy sources to ensure a stable transition to renewables.

COP28 President Sultan Al Jaber said before the climate talks that while a phasedown is “inevitable”, it can only happen when the world has added a sufficient amount of renewable energy capacity.

“You can’t unplug the world from the current energy system before you build the new energy system,” he said. “It’s a transition: transitions don’t happen overnight, transition takes time.”

COP26 in November 2021 marked the first time that the decision text from the climate talks acknowledged that fossil fuels are contributing to climate change. It called for a “phasedown of unabated coal power”.

And at COP27, a deal to phase down all fossil fuels failed to cross the line after it was blocked by some oil and gas-producing countries, which advocate instead for the use of carbon capture technology.

Carbon capture can help tackle emissions from power plants and industrial facilities that use fossil fuels, the World Economic Forum’s Fostering Effective Energy Transition 2023 report says. But it points out that there needs to be a 40-fold rise in carbon capture capacity by 2030 to put the world on track to hit net zero by 2050.

“To retain any chance of limiting global warming below 1.5°C by the end of this century, global emissions must decrease by around 7% annually until 2030,” the Forum adds in its new The State of Climate Action report. However, emissions are currently rising by 1.5% a year.

Fossil fuels still make up around 80% of global primary energy production.

On top of this, the world is perilously close to using up its “carbon budget” – the amount of carbon we can burn without breaching 1.5°C temperature rises – says the Intergovernmental Panel on Climate Change says.

“This leaves no room for new coal mines, oil and gas fields, or fossil-fuel-burning power plants, unless existing infrastructure is retired early,” UNEP adds in its report.

Over 150 countries have pledged to work towards net-zero emissions, yet the UNEP’s Production Gap Report 2023 says that projections suggest fossil fuel production will keep rising for years. The current trajectory is that global coal production will increase until 2030, and oil and gas production will increase until at least 2050, it says.