Explained: How does the world cut emissions without turning the lights off?

Finding sustainable ways to cut greenhouse gas emissions is crucial to saving the planet

Beta V.1.0 - Powered by automated translation

This week the UAE said it would go further to limit its greenhouse gas emissions.

Officials want the UAE’s 2030 emissions to be 31 per cent less than they would have been under a “business as usual” scenario.

This updated aim — up from a previous pledge of a 23.5 per cent cut — was detailed in the UAE’s Nationally Determined Contribution (NDC), a figure nations submit to the UN as part of their Paris Agreement on climate change commitments.

Heavy investments in solar power and nuclear power are helping the UAE to reduce its dependence on emissions-generating fossil fuels in energy generation.

But what is happening globally when it comes to emissions? Here, we look at the key emissions and outline how nations are limiting their contribution to climate change.

What are greenhouse gases?

Greenhouse gases is a catch-all phrase to describe carbon dioxide, methane, nitrous oxide and some synthetic chemicals.

Most enter the air as substances are burnt. These gases trap some of the Earth's outgoing energy and retain heat in the atmosphere.

The reductions have to happen, not by bottoming out the economy, but producing energy in clean ways
Asher Minns, Tyndall Centre for Climate Change Research, University of East Anglia

In the past 150 years we've been producing a lot of these gases by burning fuel to power machines, homes and vehicles, and manufacturing billions of everyday goods. And we've really stepped it up in the past few decades.

This changes the radiative balance of the Earth — that's the careful balance between energy from the sun and emitted from Earth — and makes the planet hotter.

That in turn affects ocean temperatures, raises sea levels, disrupts wildlife and causes chaos with weather patterns.

Where do the gases come from?

Overall, 65 per cent of global greenhouse gas emissions consist of carbon dioxide from fossil fuel burning and industrial processes, while 11 per cent is CO2 from forestry and other land uses.

A further 16 per cent is methane, 6 per cent is nitrous oxide and 2 per cent is fluorinated gases, Intergovernmental Panel on Climate Change figures indicate.

The burning of fossil fuels to produce energy accounts for about 72 per cent of greenhouse gases globally, according to figures published by the Centre for Climate and Energy Solutions.

This includes electricity and heat generation (31 per cent of global greenhouse gas emissions), transportation (17.2 per cent when shipping is included), manufacturing and construction (12.4 per cent), other fuel combustion (8.4 per cent) and fugitive emissions, such as leaks (5.2 per cent).

Animal and crop production in agriculture accounts for 11 per cent of global greenhouse gas emissions, while land use change and forestry, which includes the clearing and burning of forests for agriculture, is responsible for a further 6 per cent. Other industrial processes also account for 6 per cent, while waste is responsible for 3 per cent.

Within transportation, OurWorldinData reports that 45.1 per cent of emissions are from passenger road transport (including cars and buses), while road freight transport causes 29.4 per cent. Aviation emits 11.6 per cent of transport’s share of greenhouse gases (or about 2 per cent of all global emissions), while shipping accounts for 10.6 per cent of transport’s share and rail just 1 per cent.

How can emissions be reduced?

Germany's decision to axe all of its nuclear plants by 2022 in the wake of the Fukushima accident in Japan a decade ago is now seen as a huge mistake. It made Europe's most populous nation heavily reliant on coal-fired plants and Russian gas, which has since been cut off. EPA

The United Nations says replacing coal, oil and gas-fired power stations with renewable energy, such as wind and solar, is “a key element” of cutting emissions.

Certain fossil fuels emit much greater quantities of greenhouse gases, so some governments are focusing on reducing or eliminating their use.

For example, coal accounts for about 14 per cent of US energy consumption from fossil fuels, yet is responsible for 21 per cent of US energy-related carbon dioxide emissions.

By contrast, natural gas accounts for about 41 per cent of the country’s energy consumption from fossil fuels, but is to blame for only 34 per cent of American energy-related carbon dioxide emissions, illustrating that it is a much lower emitter.

Petroleum is in the middle, accounting for both 46 per cent of US energy consumption from fossil fuels and 46 per cent of the country’s energy-related carbon dioxide emissions.

There are ways to make fossil fuels less carbon intensive and more efficient, as outlined here.

How the UK ditched dirty coal

The UK is among the leaders when it comes to reducing emissions, in large part thanks to its move away from coal. Around a decade ago, coal provided about 40 per cent of the UK’s electricity supply, according to government figures, but by last year that had fallen to 1.8 per cent.

Some big emitters, notably China, are building multiple new coal-fired power plants, although Beijing has pledged to reduce coal use in future.

Renewable energy sources account for a greater share of global electricity generation, with the figure increasing from 27 per cent in 2019 to 29 per cent in 2020. Two thirds of the growth in renewables is set to come from wind and solar power.

As recently as a decade ago, the UK generated about 40 per cent of its electricity supply from burning coal. With heavy investment in renewables, that has fallen to less than 2 per cent today. AFP

The UAE has invested more than $40 billion in clean energy, including renewables and nuclear, notably through vast expansion in solar power capacity and the building of the four-reactor Barakah Nuclear Power Plant.

As noted, transport accounts for about 17.2 per cent of global greenhouse gas emissions, so transitioning to electric vehicles powered by electricity generated by renewables “would play a huge role” in lowering global emissions, according to the UN.

The EU recently gave the green light to a 2035 ban on the sale of vehicles with combustion engines, with limited exceptions. California recently made a similar decision, a move observers expect other US states to follow.

Are countries doing enough to reduce their emissions?

The aim of the 2015 Paris Agreement on climate change was to limit global temperature rises by the end of the century to 1.5°C above pre-industrial levels or, failing that, to 2°C.

There is no realistic prospect of 1.5°C being kept to, while analysis by Carbon Brief, a UK climate and energy website, suggests 2°C will be breached around 2043.

The UAE is among the countries to have pledged to reach net zero by 2050, although some major economies like China have a 2060 target.

According to Asher Minns, executive director of the Tyndall Centre for Climate Change Research at the University of East Anglia in the UK, many nations are not moving fast enough to meet their commitments.

'Alice', the world's first all electric passenger plane built by Eviation Aircraft, in Arlington, Washington state. If such aircraft can be scaled up, they could slash emissions in the aviation industry. Getty Images

“NDCs shouldn’t be aspirations, they should be actual targets,” he said. “I’m not sure any country is actually delivering on its NDC. Some are trying harder than others.”

Indeed he said global carbon emissions have largely rebounded upwards after falling as a result of the Covid-19 pandemic.

Last year’s global energy-related carbon dioxide emissions were 36.3 billion tonnes, their highest ever level, according to the International Energy Agency, with an increase in coal burning largely to blame.

Nonetheless, Mr Minns added that “lots of economies have reduced their carbon emissions”, proving that the emissions curve can be turned downwards if efforts are made.

“The reductions have to happen, not by bottoming out the economy, but producing energy in clean ways,” he said. “We have the technology, it just needs investment. That’s what people want to see.”

Updated: September 14, 2022, 7:59 AM