Carbon footprint
What is a carbon footprint, and why is it so important to reduce it in order to minimise climate change?
Energy efficiency Decarbonisation Climate action
The carbon footprint is the invisible trail our actions leave on the planet. It represents the total amount of greenhouse gases we generate, both directly and indirectly. Among them is carbon dioxide (CO₂), the main driver of global warming since 1990. In this context, what actions should we take to reduce it?
The trace of the greenhouse gases produced by human activities is known as the carbon footprint.
Whether we are driving a car, taking an aeroplane journey or even consuming everyday foodstuffs such as beef, we are leaving an invisible carbon footprint. So many of our day-to-day activities leave a trail of greenhouse gas emissions behind, gases that are released into the atmosphere and trap heat, thus contributing to climate change. Being aware of an activity’s carbon footprint, which is measured in tons of CO2, is important when it comes to taking measures and launching initiatives to reduce these emissions to the lowest possible level. The responsibility for doing so, in order to avoid catastrophic climate change, falls to individuals, companies and governments.
What is a carbon footprint?
The trace of the greenhouse gases produced by human activities is known as the carbon footprint. This environmental indicator measures both direct and indirect emissions of compounds such as methane (CH4), nitrogen oxide (N2O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), sulphur hexafluoride (SF6) and, above all, the most abundant and most important contributor to global warming since 1990: carbon dioxide (CO2).
How to calculate your carbon footprint
Knowing your carbon footprint is the first step to reducing it, not just offsetting it. Use our online calculator to estimate the emissions of your household or business, based on your consumption habits, transport and lifestyle. Compare your results with national and global averages and discover how to reduce your environmental impact.
Knowing your carbon footprint, whether at a personal or organisational level, is useful for a number of reasons:
- Identification and reduction of emissions: It allows you to identify sources of greenhouse gases (GHGs) and establish measures to reduce them.
- Corporate transparency: Companies can use this information to publish statistics on their environmental performance, strengthening their commitment to sustainability.
- Awareness raising: Serves as an educational tool to help raise awareness among individuals and organisations about the environmental costs of their activities.
- Environmental and energy management: It facilitates the design and implementation of more efficient strategies to manage resources and reduce negative impacts on the environment.
In short, carbon footprinting is a key tool for moving towards more sustainable development.
What factors have the greatest impact on our carbon footprint?
A personal carbon footprint is the environmental impact we generate through our daily activities, from how we travel to the food we eat. Although every action counts, some factors have a much greater impact than others. Understanding how each of us contributes to greenhouse gas emissions can help us make more sustainable choices and reduce our footprint. Below are some of the main factors that affect it:
Family size
According to Conservation International, no other single factor has such a big effect on your carbon footprint as the number of children you have. Each child in your family adds an average of 58 tonnes of CO2-equivalent every year, according to the organisation. This impact exceeds that of other individual habits or decisions, underlining the importance of considering family size in the context of environmental sustainability.
Transportation
Cars and aeroplanes are two of the biggest contributors to personal carbon footprints. Car owners who regularly use their vehicle generate, on average, 2.4 tonnes of CO2 per year. Meanwhile, a single transatlantic flight has a significant impact, adding around 1.6 tonnes of CO2.
Heating and air conditioning
If you need to regularly heat and cool your home, depending on the season, you are likely adding 1.5 tonnes of CO2-equivalent to your annual footprint, especially if your energy is coming from so-called “dirty” sources such as coal and gas instead of renewables. Coal, for example, produces 870 grams of CO2 per kilowatt of power, according to Conservation International, compared to just 48 grams of CO2 for solar and 11 grams for wind.
Food
Meat adds around 0.8 tonnes of CO2-equivalent to your annual carbon footprint, partly due to the emissions of gases such as methane from the animals’ digestive tracts, but mostly because of the energy required to grow, harvest and process crops that are used as feeds for the livestock.
Water
Daily water consumption also has a carbon footprint, as energy is required to extract, treat and distribute it. Excessive use of water – such as overwatering, taking long showers or doing laundry too frequently – increases energy demand and therefore emissions. What’s more, heating water, especially using electricity or gas, further increases the carbon footprint unless more sustainable solutions are used, such as solar water heaters.
How citizens can reduce their carbon footprint
Travelling in a more sustainable way
Walking, riding a bike, carpooling and using public transport are all great ways to reduce your carbon footprint. And if you do have to fly, it is better to take nonstop flights rather than connecting flights with layovers, as they are more fuel efficient.
What’s more, some carriers allow their customers to pay money into a sustainable flight account when booking trips. The funds raised go towards projects such as research and development of sustainable aviation fuels, promoting a more environmentally friendly future for the air transport sector.
Promoting sustainable food
In order to bring down your carbon footprint, it is better to buy local produce rather than mass-produced groceries, as well as opting for lower-carbon options such as vegetables instead of beef.
Livestock farming is a major source of methane emissions, a greenhouse gas released during the digestive process of animals such as cows. According to some researchers, switching from a meat-based diet to a vegetable-focused diet can reduce the carbon footprint associated with food by 50-80%.
Fashion
To keep your carbon footprint low, it is important to avoid so-called “fast fashion” – i.e. cheap garments that are not designed to be worn for long and instead keep pace with ever-changing trends. The fashion industry accounts for 10% of global carbon emissions every year, according to the UN, and these emissions could increase by more than 50% by 2030 if current trends continue.
Buying clothes made of wool or cotton, rather than synthetic fabrics, is a good way to bring down your carbon footprint.
Promoting energy efficiency in buildings
Electronic devices left on standby mode account for 5-10% of residential energy use. To reduce your carbon footprint, it is advisable to unplug them when they are not in use.
What’s more, opting for energy-efficient lighting, such as LED bulbs, is a great way to reduce electricity consumption and associated emissions.
More and more manufacturers are also specifying the carbon footprint of their products, giving consumers the opportunity to make informed decisions and more sustainable choices when shopping.
What factors have the greatest impact on a company’s carbon footprint?
Just like individuals, companies generate greenhouse gases (GHGs) through their manufacturing, transport and energy consumption processes. A company’s carbon footprint assesses all these emissions, both direct and controllable ones, as well as indirect ones.
In this regard, companies usually have the option to reduce or offset their carbon footprint. How? These are the factors that have the greatest impact on a company’s carbon footprint:
Energy consumption
Companies that rely on non-renewable energy sources, such as coal or natural gas, have a higher carbon footprint. Factories, offices and other facilities that consume large amounts of energy are responsible for a high volume of CO2 emissions. The transition to 100% renewable energy can significantly reduce this impact.
Transport and logistics
The transport of goods and materials, whether by lorry, ship, plane or train, accounts for a large part of a company’s carbon footprint. Companies with global operations, which require international shipments, tend to generate higher GHG emissions due to the intensive use of fossil fuels in transport.
Manufacturing and production processes
Industrial processes, particularly in sectors such as the manufacture of chemicals, metals and cement, emit large quantities of CO2 due to the use of heavy machinery, fossil fuels and the need for high temperatures. Optimising production efficiency and adopting cleaner technologies can significantly reduce emissions.
Supply chain
Indirect emissions generated by a company’s suppliers also affect its carbon footprint. This includes emissions associated with the production of raw materials, their transport and the processing of products. Companies can collaborate with suppliers to reduce emissions throughout the supply chain.
Carbon footprints in figures
16 tonnes
The average carbon footprint for a person in the United States
4 tonnes
The average global carbon footprint per person
<2 tonnes
The target footprint to avoid a 2ºC rise in global temperatures
16 tonnes
The average carbon footprint for a person in the United States
4 tonnes
The average global carbon footprint per person
<2 tonnes
The target footprint to avoid a 2ºC rise in global temperatures
Net Zero
Net zero 2030
What is decarbonization?
Regulatory principles and actions relating to energy decarbonisation
What is energy efficiency?
The benefits of energy efficiency
Carbon markets
How are emission allowances and carbon credits markets regulated?
Carbon neutrality
Carbon neutrality, what is it and why is it vital for the future of the planet?
Science Based Targets
The Science Based Targets initiative
The role of offsetting schemes in reducing a carbon footprint
If an individual cannot – or does not want to – avoid an activity that leaves behind a carbon footprint, they now have a wealth of options and schemes when it comes to offsetting those greenhouse gas emissions. Offsetting is a climate action that is available to both individuals and companies, and allows them to compensate these emissions by supporting worthwhile projects that reduce emissions elsewhere.
To be able to quantify this offsetting, the United Nations (UN) has created a measurement called Certified Emission Reductions (CERs). CERs are generated by what are classed Clean Development Mechanism (CDM) projects, which are located in developing countries, and earn one CER for every metric tonne of greenhouse gas emissions that they either reduce or avoid. These in turn are measured in CO2 equivalent, which is represented by the symbol CO2-eq.
CERs can then be purchased by individuals or by organisations as a way of offsetting their own emissions. The UN describes the scheme as like “crowdfunding for climate action”, as purchasing CERs is a direct financial contribution to projects that not only reduce emissions, but also benefit communities.
It is important to note that, when selecting projects for carbon offsetting, consideration must be given not only to the amount of CO₂ reduced, but also to the quality of the projects. Offset projects must be assessed in terms of their actual effectiveness and long-term sustainability. Furthermore, nature-based solutions, such as reforestation and ecosystem conservation, offer additional benefits, such as the restoration of biodiversity, the strengthening of natural habitats and support for the resilience of local communities in the face of climate change.
The impact of these projects is measured not only in terms of greenhouse gas emission reductions, but also in terms of their contribution to biodiversity and social development. Implementing projects that respect and promote biodiversity, whilst supporting the economic and social development of the most vulnerable communities, ensures a more comprehensive and positive approach to tackling global climate challenges.
How do offsetting projects reduce emissions, and what are their benefits?
According to the UN, CDM projects have been responsible for avoiding more than 1.8 billion tonnes of greenhouse gas emissions so far, which is the equivalent of taking more than 300 million cars off the road or installing 400,000 wind turbines. Here is how CDM projects can reduce emissions.
- Transition to clean energies: Replacing the use of polluting fossil fuels with clean, renewable energy such as wind, hydro, solar and biomass.
- Energy efficiency: Reducing energy consumption and fossil fuels through energy-efficiency measures, such as clean cooking stoves and energy-efficient light bulbs.
- Carbon capture: Through natural sinks such as trees and other plants, reforestation and forest-regeneration projects sequester carbon that has already been released into the atmosphere, helping to restore the environmental balance.
What are the benefits of carbon offset projects?
If the objectives of the Paris Agreement are to be met, and the global temperature rise is limited to less than 2ºC before the end of the century, offsetting projects will play a key role. Their aim is to bridge the gap between the present day and a future moment when societies have phased out technologies that pump greenhouse gases into the atmosphere. Among the benefits of these offsetting projects, according to the UN, are:
Supporting sustainable development: They contribute to the economic and social development of developing countries, creating opportunities that benefit local communities.
Multiple benefits for communities: They address climate change while improving people's quality of life, driving improvements in areas such as health, education and wealth creation.
Promoting responsible industrial practices: They help promote a shift towards more sustainable and responsible industrial practices, encouraging companies to adopt clean technologies and reduce their environmental impact.
Encouraging behavioural change: Offset projects encourage changes in the behaviour of both companies and individuals, including consumers. These changes can generate a multiplier effect, influencing industries, institutions and networks, accelerating the transition to a more sustainable future.
How does Iberdrola reduce its carbon footprint?
At the Iberdrola Group, with the aim of promoting a sustainable economy and helping to combat climate change, in 2023 we launched Carbon2Nature, a company focused on developing high-impact nature-based solutions projects that reduce the global carbon footprint and enhance biodiversity.
With a global vision and a strong local focus, we develop long-term conservation, restoration and sustainable land-management projects with significant climate, environmental and social impact, with the goal of achieving net zero emissions across all scopes before 2040.
Carbon2Nature is already involved in a wide range of projects in countries such as Brazil, Mexico, Colombia, Chile and Spain, helping companies to design innovative decarbonisation initiatives.
At Iberdrola, we are also making a strong commitment to electrification and the expansion of our smart grids as part of our strategy to reduce greenhouse gas emissions. The electrification of key sectors, such as transport and industry, is essential for a more sustainable development model. Our smart grids enable us to manage energy more efficiently, optimising its distribution and reducing losses, which contributes significantly to reducing our carbon footprint.
Among the most ambitious projects are:
Methane emissions reduction in the livestock sector [Spain]
A project carried out in collaboration with Mesta (Pascual) to reduce methane emissions through the supply of a feed additive, with strong involvement from the livestock sector. This project will bring significant benefits to the agricultural sector, helping to decouple its climate impact from production.
Sabancuy Project [Mexico]
A joint initiative between Carbon2Nature, ATEC and the Ejido Sabancuy to restore 500 hectares of mangrove forest, with the potential to scale up to 1,500 hectares.
Talia Project [Australia]
The Talia Project, in South Australia, stems from the collaboration between Carbon2Nature and Land Life. Its purpose is to restore 688 hectares of degraded land, with a particular focus on restoring the critically endangered Drooping Sheoak (Casuarina glauca) forest.
Muçununga Project [Brazil]
The Muçununga Project is a partnership between Carbon2Nature and Biomas. It is in southern Bahia, within a central corridor of the Atlantic Forest. The initiative will be implemented on degraded land and abandoned pasture across eight municipalities, areas with strong potential for the creation of ecological corridors.
