This briefing paper answers some commonly asked questions about improving energy efficiency in older domestic buildings. It does not focus on specific issues associated with listed or heritage buildings.
More than 190 countries have adopted the Paris Agreement, a legally binding international treaty on climate change reached at COP21 in 2015. The Agreement aims to keep a rise in global temperatures to below 2°C from pre-industrial levels, by the end of this century.
Signatories also agreed “to pursue efforts” to limit the temperature increase to below 1.5°C. To achieve the 1.5oC target, global greenhouse gas emissions will need to be ‘net zero’ by the second half of this century.
Negotiations around reducing emissions are at the heart of COP26, which started on 31 Oct 2021. To date, only the UK and 11 other countries have passed legislation on net zero targets, although many others have made policy commitments.
This Insight looks at progress towards reaching net zero.
IPCC, 1.5oC and net zero targets
The Intergovernmental Panel on Climate Change (IPCC) published a special report on the impacts of global warming of 1.5oC in 2018. The report found there would be severe climate impacts with 1.5oC of warming but the that effects would be significantly worse with 2oC.
It also stated that emissions would need to peak before 2030 to limit temperature rises to 1.5oC and net zero emissions globally needed to happen by around 2050.
In simple terms, ‘net zero’ means our total emissions are equal to or less than the emissions we remove from the environment. This can be achieved by a combination of emission reduction and removal by offsetting.
Achieving actual zero greenhouse gas emissions is not seen as a realistic option. Instead, net zero emissions would mean that any emissions that could not be eliminated by 2050 would be compensated for by measures that remove emissions from the atmosphere (sequestration).
In response to this a number of countries, including China and the US have set a net zero emission target.
Who are the biggest emitters?
The chart below shows the top 10 emitters of greenhouse gases globally, compared with the UK and the rest of the world. The top 10 emitters account for over two thirds of global emissions (though note that the EU is counted as a single ‘emitter’ in this data).
China is responsible for over a quarter (26.1%) of global GHG emissions. The USA is the second largest contributor of GHGs, responsible for around 12.7% of emissions.
The UK is the 17th largest emitter of emissions.
Legally binding targets
Of the top ten GHG emitters, only Japan, Canada and the EU have legally binding net zero commitments.
In December 2000, the EU’s member states jointly committed to a binding target of a net domestic reduction of at least 55% in GHG emissions by 2030, compared to 1990 levels. The EU has set out a long-term strategy of becoming climate neutral by 2050.
Specific targets have been agreed for individual EU countries (PDF, 905 KB) under a burden sharing agreement.
Sweden and Germany have legally binding net zero targets for 2045. France, Denmark, Spain, Hungary and Luxemburg have set theirs for 2050.
Japan, Korea, Canada, and New Zealand have passed laws committing to achieving net zero by 2050 while Ireland, Chile and Fiji have proposed legislation.
The UK has a legally binding net zero target by 2050 and new interim targets to reduce emissions by 78% by 2035.
It’s not clear how the legally binding nature of these targets would be enforced if a Government failed to meet them. However, such targets can make governments more strategic and focus on long-term goals.
How much of the world has net zero commitments?
Information from the UN shows more than 130 countries have now set or are considering a target of reducing emissions to net zero by 2050.
The website Netzerotracker keeps track of commitments made by countries. As of 11 November 2021, it showed that eight countries had self-declared they have achieved net zero. It says that a further 16 countries have a pledge in law, 59 in a policy document, 21 another kind of declaration or pledge, and 72 countries are discussing or proposing a pledge.
The largest emitter, China has a commitment is to reach carbon neutrality by 2060, although this is not legally binding. The USA’s Pathways to Net-Zero Greenhouse Gas Emissions by 2050 (PDF, 3.5 MB) outlines its commitment to achieving net zero by 2050. However, like China, it has not set a legally binding target.
Announcements ahead of COP26
There were several announcements in the run up to COP26. Some – such as the commitment from Australia – have been criticised for lack of detail.
In October, Russia announced its commitment to net zero by 2060. In the build up to COP26, Boris Johnson, spoke with Russian President Vladimir Putin and said he hoped Russia will bring forward its target to 2050. Saudi Arabia has also committed to achieving this by 2060.
India’s prime minister, Narendra Modi, announced at the COP26 world leaders’ summit that the country would meet a target of net zero emissions by 2070.
On 10 November, China and the USA issued a joint statement outlining their commitment to tackling the climate crisis and that they would continue to discuss “concrete actions in the 2020s to reduce emissions aimed at keeping the Paris Agreement-aligned temperature limit within reach.”
- United Nations Climate Action, United Nations
- UNEP: Current climate commitments are ‘weak promises, not yet delivered’, Carbon Brief 26 October 2021
- COP26: How every country’s emissions and climate pledges compare, Financial Times 26 October 2021
- History of net zero infographic, the Energy and Climate Intelligence Unit
About the author: Dominic Carver is a researcher at the House of Commons Library, specialising in Water, the Environment and Climate Change.
A Westminster Hall debate on the British Energy Security Strategy is scheduled for Tuesday 5 July 2022, from 2:30-4:00pm. The debate will be led by Mick Whitley MP.
Estimates Day debate: The Spending of the Department of Business, Energy and Industrial Strategy on action on climate change and decarbonisation
On Tuesday 5 July the House of Commons will consider estimates of spending on climate change and decarbonisation as part of the Estimates Day debate. This briefing provides background information for the debate and also parliamentary and media coverage of the issues.