What is Decarbonisation and net zero?

Jul 25, 2023

Not a day goes by that there isn’t a new a report, seminar or article on the challenges of decarbonising and net zero. Indeed the Intergovernmental Panel on Climate Change (IPCC) Climate Change 2023: Synthesis report shows damming evidence that we are not doing enough to decarbonise, adding that carbon dioxide (CO2) is at its highest level in the atmosphere for 2 million years. But what does it all mean? Why is CO2 so bad? Is climate change the disaster the United Nations (UN) et al makes it out to be? And what are the impacts if we don’t implement change? In this article we discuss the key issues, and why it is imperative we cut greenhouse gas emissions.

Decarbonisation and net zero definitions

Let’s start with the basics:

Greenhouse gases (GHG) trap heat in the atmosphere, warming the Earth’s air, land and sea temperatures, just like a greenhouse. The most common GHG is carbon dioxide. Man-made CO2 is produced through burning fossil fuels to provide heat and energy. There are a number of greenhouse gases, including methane (Ch4), nitrous oxide (N2O) and fluorinated gases (F gases), which are typically used as refrigerants.

Climate change is the long-term change in temperatures and weather patterns. Climate change can be natural e.g. through variations in the solar cycle, or due to human activities e.g. man-made GHG emissions.

Decarbonisation is simply reducing the amount of carbon dioxide, and other greenhouse gas emissions, that are produced and released into the atmosphere.

Net zero is to bring those greenhouse emissions as close to zero as possible, with any remaining emissions re-absorbed from the atmosphere by other means, such as oceans or forests.

Why do we need to decarbonise?

While some GHGs occur in the environment naturally, it is those due to human activity that are causing harm. Since the industrial revolution, man-made GHG emissions have grown hand-in-hand with the Earth’s temperature. The Earth is approximately 1.1oC warmer than it was from 1850-1900. While this may seem insignificant, countries across the globe are already feeling the dire consequences of climate change. Sadly some of these impacts are irreversible and temperatures are set to rise further.

 The most concerning climate change effects include:

  • Loss of glaciers, ice sheets and permafrost
  • Extreme heat and an increase in heat waves
  • Extreme rainfall
  • Extreme storms and tropical cyclones (hurricanes).

These issues result in:

  • Water scarcity
  • Rising sea levels
  • Ocean acidification
  • Loss of land mass
  • Loss of biodiversity
  • Extinction of different species on land and sea
  • Droughts
  • Wildfires
  • Flooding
  • Water pollution
  • Damage to infrastructures, homes and buildings
  • Failure of harvests
  • Impacts on food production
  • Famine
  • Excess deaths
  • Ill health and an increases in disease
  • Negative impacts on local economies
  • Poverty.

No one will escape the consequences of climate change. Sadly it is those communities who have historically contributed the least GHG emissions that are disproportionately affected. This includes third-world countries and low-lying island nations such as the Maldives. However, first-world countries are not immune and deaths due to extreme weather conditions are rising. In France the 2022 heatwaves were linked to thousands of heat related deaths. 10,420 excess deaths were recorded between June-September, with 2,816 excess deaths during three heatwave alerts. There is only one answer; limiting human-caused global warming requires net zero CO2 emissions, and a substantial reduction in other GHG emissions.

How do we decarbonise?

Signatories of the Paris Agreement pledged to keep the mean temperature rise well below 2oC, and ideally limit it to 1.5oC. However, the IPCC Climate Change 2023: Synthesis report shows that the 1.5oC limit is likely to be breached in the 2030s, unless current emissions are cut by almost half by 2030, and that we are on track to break the 2oC limit also. The report stresses that, all global modelled pathways that limit warming from 1.5°C to 2°C, “Involve rapid and deep and, in most cases, immediate greenhouse gas emissions reductions in all sectors this decade.”

We need to decarbonise by cutting our reliance on fossil fuels, along with products, processes, materials and activities that emit GHGs. Main areas include:

  • Decarbonising energy production and the grid via renewables, nuclear, hydrogen and sustainable bio fuels
  • Increasing the efficiency of anything that uses energy, (buildings, products, manufacturing processes etc.) to reduce overall energy consumption and demand
  • Phasing-out of fossil fuels in favour of electrification.

The challenge is to implement decarbonisation across a number of sectors, including:

  • Agriculture
  • Building and construction
  • Forestry
  • Health
  • Manufacturing
  • Mining
  • Retail
  • Transportation
  • Tourism.

Figures from the UN Environment Programme Emissions Gap Report 2022 show that the top seven emitters (China, USA, India, the European Union (EU), Indonesia, the Russian Federation and Brazil) accounted for around half of global GHG emissions in 2020. Additionally, the Group of 20 (Argentina, Australia, Brazil, Canada, China, France, Germany, India, Indonesia, Italy, Japan, Republic of Korea, Mexico, Russia, Saudi Arabia, South Africa, Turkey, the United Kingdom, USA, and the EU) are responsible for around 75% of global GHG emissions.

More than 70 countries have set a net zero target by 2050, covering around 76% of global emissions. However, current commitments fall short, and some of the highest polluting countries have agreed to net zero over a longer timeframe. The biggest producer of CO2, China, has pledged to ‘carbon neutrality’ before 2060, Russia is aiming for net zero by 2060, and the fourth biggest producer of CO2, India, is aiming net zero by 2070. The good news is that you don’t have to wait for government legislation to decarbonise, and that our actions as individuals can make a difference.

How can I decarbonise?

In the EU for example, heating and cooling accounts for around half of a building’s annual energy use. When it comes to decarbonisation, heating, ventilation and air conditioning (HVAC) systems sit at the heart. When it’s time to replace older technologies, switch to an energy efficient, low carbon alternative. In terms of HVAC, this may be swapping a gas boiler for an air source heat pump, or a cooling system using a high GWP refrigerant to an energy efficient alternative with a low GWP.

For most existing buildings, upgrading HVAC equipment won’t be the only steps you can take. Unless your building is already working at its peak efficiency, the building envelope (e.g. roof, insulation, windows and doors) may require energy efficiency upgrades to decarbonise. It should also be noted that ventilation requirements may change with higher building envelope efficiencies, to prevent issues such as condensation and mould. The good news is that depending on the country you live in, financial help may be available to enable energy efficiency improvements and encourage the installation of low carbon technologies.

💡 Good to know

If you can’t install your ideal low carbon system now, upgrading old equipment to an energy efficient alternative will still make a positive impact on your carbon emissions, and your energy bill.

The best way to choose an energy efficient HVAC system is to compare independently verified certified products to make an informed decision. This is because certified products:

  • Are directly comparable. Their performance is evaluated according to the same criteria, and the results expressed in the same unit of measurement, regardless of the country where the products are manufactured or marketed
  • Have performance verified by an impartial, independent and competent accredited body
  • Are guaranteed to comply with regulations, standards and codes
  • Provide assurance that HVAC systems will perform as expected.

Check out our certified product directory to view products by family, type, brand, model name and certificate number. Search for energy efficient certified products now and begin your net zero journey.

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