Carbon neutrality: 10 questions and answers

9 April, 2024

Undoubtedly, one of the issues of greatest concern to society today is climate change. Rising temperatures, chiefly due to human activity, are responsible for alterations in nature that endanger the different ecosystems and, incidentally, the very future sustainability of human beings. Higher temperatures, more intense storms, longer droughts and loss of biodiversity are some of the negative effects of this climate emergency.

Greenhouse gas (GHG) emissions, mainly carbon dioxide (CO2), contribute to rising temperatures by acting as a heat-trapping layer in the atmosphere. Therefore, eliminating, reducing or offsetting these emissions must be one of our society’s goals to achieve carbon neutrality. Here we explain what carbon neutrality is, its characteristics and the role played by renewable gases such as green hydrogen among other aspects.

1. What is the carbon footprint?

Carbon footprint is the calculation of the amount of greenhouse gases emitted, directly or indirectly, over a period of time. Although GHGs include not only carbon dioxide (CO2) but also gases such as methane (CH4) or nitrous oxide (N2O), it is called a carbon footprint because it is carbon dioxide that has the highest concentration. The increase in the levels of these gases in the atmosphere over the last decades is one of the main causes behind climate change.

The World Meteorological Organisation points out that current atmospheric CO2 levels are similar to those existing on our planet more than three million years ago, when the earth’s thermometer was almost 3°C higher and sea levels were 10 to 20 metres higher than they are today.

2. How are CO2 emissions calculated?

The calculation of CO2 emissions changes depending on the type of fuel that emits them, as well as the way in which they are generated. In business, one of the most widespread classifications is that of scopes:

Scope 1. These are the direct emissions that an organisation or entity has and that are produced by the burning of fossil fuels in the processes under its control. For example, emissions from the fossil fuel used by the machinery used in its production chain or from its transport fleet.

Scope 2. These are the indirect emissions associated with the generation of electricity purchased and consumed by the organisation. They are considered indirect as they are not under the direct control of the organisation. For example, electricity purchased to run equipment does not emit the same levels of GHGs if it comes from renewable sources or fossil fuel sources.

Scope 3. These are also considered as indirect emissions and include those produced by the different elements of the organisation’s value chain, both upstream (e.g. emissions from suppliers) and downstream (e.g. emissions generated by customers in the use of products or services).

3. What is carbon neutrality??

Achieving carbon neutrality means achieving a balance between CO2 emissions that are released into the atmosphere and those that are removed. Experts say the best way is to eliminate emissions at source. Once the maximum possible reduction has been achieved, offsetting of the remaining emissions is addressed until neutrality is reached. There are several options to achieve this offsetting, such as carbon sinks, which are natural reservoirs – oceans and forests, for example – that absorb and capture carbon dioxide from the atmosphere, thereby reducing its presence in the air.

4. What does it mean to be zero carbon?

We talk about zero carbon when there are no carbon emissions during the activity carried out to produce a good or service. For example, a commercial building is considered zero-emission if it runs entirely on clean or renewable energy.

5. What is it to be carbon negative??

Carbon negative arises when a person, company or sector removes more GHGs than emitted, thus generating a positive impact on the atmosphere. From 2050 onwards, it will be necessary to eliminate more greenhouse gases than are emitted to ensure that future generations have the environment and natural resources necessary for their sustainability.

6. How can carbon be removed from the atmosphere?

By capturing CO2 from a point source, such as a power plant or factory, before it is emitted into the atmosphere. Once captured, the CO2 is safely stored or used as a raw material in other production processes.

In addition, there are other mechanisms for removing carbon from the atmosphere. These include reforestation, ocean fertilisation to increase phytoplankton uptake and projects to avoid deforestation.

7. What commitments are there on carbon neutrality?

The European Green Deal is a set of initiatives adopted by the European Commission with the aim of driving forward the ecological transition to ultimately achieve climate neutrality by 2050. EU member states must reduce their GHG emissions by at least 55% by 2030 and achieve GHG neutrality by 2050.

To achieve these aims, measures such as investing in environmentally friendly technologies, developing clean transport methods, decarbonising the energy sector or facilitating the financing of green projects have been proposed.

8. What is the role of renewable hydrogen in carbon neutrality??

Renewable hydrogen is one of the ideal energy carriers to combat climate change. It is a clean and versatile energy, produced using electricity from renewable sources such as wind, solar and hydroelectric power, which do not emit GHGs.

The Roadmap to Net Zero by 2050, published by the International Energy Agency (IEA) in 2021, states that hydrogen and hydrogen-based fuels, provided they are produced with low CO2 emissions, have a key role to play in achieving carbon neutrality.

9. What can citizens do to achieve carbon neutrality?

Making changes at home, in transport or in some daily habits can contribute to reducing your personal carbon footprint. In the case of housing, it is possible to use energy efficiency measures, such as thermal insulation, low-energy appliances, or making the most of natural light.

In terms of mobility, as well as thinking about alternatives that run on low-emission energy sources, there are options such as car sharing, using public transport, cycling or walking where possible, for example.

10. What is the Paris Agreement??

The Paris Agreement is the first universally binding agreement on climate change. It was adopted at the COP21 in Paris in 2015 with the aim of preventing the average global temperature from rising above 2ºC.

The signatory countries committed to achieving carbon neutrality by 2050, which implies implementing a series of measures to limit global warming to 1.5°C above pre-industrial levels.