Frequently asked questions

In other words, how is it that what I eat or my garbage emit greenhouse gases (GHGs)?

Everything we consume, use and then throw away requires materials and energy. This applies to the production, use and end-of-life phases of goods and services. As a result, all our activities contribute to greenhouse gas emissions. Some enormously, others very little.

Eating a kg of potatoes, driving a car 10,000 km, watching a streaming video... all emit greenhouse gases (GHGs), but obviously in very different proportions. And we don't always have these figures in our heads.

To estimate our own contribution to global warming (our "climate impact"), we usually calculate our individual carbon footprint.

To find out how much each of our actions emits, we rely as soon as we can on the Base Carbone of ADEME (the French Agency for Ecological Transition). This database contains hundreds of "emission factors" derived from life-cycle analyses, enabling us to go from kilometers driven, kilograms of meat, kWh consumed, of a TV to the quantity of greenhouse gases emitted.

The aim of Nos Gestes Climat is to manipulate these figures to simply question our lifestyles in order to identify what contributes more or less to our carbon footprint.

💡 To discover the climate footprint consumption by consumption, do not hesitate to continue on impactCO2.fr after your Nos Gestes Climat test.

By far the most advanced version of the model is for Metropolitan France. Little by little, as contributions and requests come in, we're adding building blocks to improve versions dedicated to overseas territories, or to other countries. The available countries can be found on our International page. For the time being, these are "beta" versions, not yet finalized.

In addition, the model has already been translated into English, for greater inclusiveness.

Why is internationalization important? Certain parameters of the model, in particular the footprint of the electricity mix (in gCO₂ₑ/kWh), particularly influence the final result, which will therefore not be valid in Belgium, Congo, Quebec, Algeria or elsewhere. Wondering what your footprint would look like in one of these countries? You can change region on this page.

If you're familiar with the subject in your country or region, come and discuss it.

Nos Gestes Climat is an individual carbon footprint calculator

However, some questions can be confusing (such as the number of people living in your home or the average number of passengers in your car). These questions are there so that we can bring a wider impact to the individual scale.

For some consumer goods, this distinction is not always clear.

Indeed, within a household, it is very difficult to arbitrate between certain goods and services used for personal consumption and others that can be shared (hifi or computer equipment, tools, etc.).

For each of them, we have therefore arbitrated between personal and shared (the television is shared, the computer is personal). If the distinction isn't the same for you, don't worry: these items represent very little in your final footprint.

At the same time, the team is working on developing a **household course so that you can estimate your family's carbon footprint.

It's a complicated subject, to say the least!

Nos Gestes Climat is an individual footprint simulator. We consider that every human being, child or adult, has his or her own footprint.

Of course, a child has not chosen to be born, and somewhere one or two adults have decided to bring a new individual into the world, who will have a carbon footprint. One might say that we should attribute it to them. But for how long? Your footprint is not to be attributed to your parents!

On the other hand, we're lucky: French demographics are fairly stable, and there's not much risk of our individual budgets melting away because of explosive demographics.

We are well aware that Nos Gestes Climat is not a complete response to the challenges we face.

Climate change is just one of the nine planetary limits</a> that we are threatening (or have already exceeded) with our lifestyles.

The "carbon" approach must therefore be complementary to the other eight limits: the erosion of biodiversity, the disruption of the biogeochemical cycles of nitrogen and phosphorus, changes in land use, the acidification of the oceans, the global use of water, the depletion of the ozone layer, the introduction of new entities into the environment (chemical pollution) and the increase in aerosols in the atmosphere.

Fortunately, many of the goods we use on a daily basis are intended to last for many years. To represent this usage, we amortize (in the same way as an accountant amortizes a purchase) the carbon impact of a portion of your goods over several years.

Cars are depreciated using a non-linear function, with the first few years "weighing" more than the following ones in terms of carbon footprint, to reflect the rapid depreciation of a vehicle after purchase, and to discourage the purchase of new vehicles.

All other tangible assets (small equipment, other vehicles, digital equipment, household appliances, etc.) are depreciated on a straight-line basis over their estimated useful life. For example, a tumble dryer has a lifespan of 10 years, so 1/10° of its construction footprint is charged each year.

It's a very complex subject, on several levels.

First, there is the problem of double counting. Emissions from fossil fuels financed by banks are counted for those who use them. Counting the footprint of savings therefore means double-counting the consumption linked to what these savings have financed.

For example, your bank may finance the extraction of oil off the coast of Siberia, but this oil is extracted so that someone, somewhere, can drive a car 10km, heat a house or produce plastic. In the model, these emissions are attributed to the consumption of cars, housing and plastic.

There is also the difficulty of accounting for the carbon footprint of savings. Initiatives do exist (such as that of Oxfam, for example), but we are far from a consensus on calculation methods.

For these two reasons, the carbon footprint of your savings is not currently assessed as part of Nos Gestes Climat.

nevertheless, we're aware that we're probably missing our educational objective here: this is a subject that still gets (too) little attention, and one on which citizens deserve to be informed. So we' re still thinking about adding an "individual savings" component to the simulator._

Let's be honest, very few people today emit less than 2 tonnes of greenhouse gases per year. If your footprint is around 4 or 5 tonnes, you've already come a long way.

It's a question of individual progress towards less greenhouse-gas-emitting lifestyles, but it's also essential that changes take place on a wider scale to facilitate the emergence of these lifestyles.

For example, a community where citizens massively take up cycling (or other low-carbon modes) will encourage its elected representatives to promote new infrastructures and appropriate policies, which in turn will help the next ones to take up cycling, and so on ♻️!

This 2-tonne target is complicated, but it's what we need to reach collectively as quickly as possible, and by 2050 at the latest, with a steady progression each year, in order to contain global warming to +2°C, and thus respect the Paris Agreement. This "climate budget" is not a political decision, but a response to the planetary limits identified by climate science. It is factual and non-negotiable, unless we wish to expose ourselves to the disastrous consequences associated with it, and widely described in the IPCC reports.

To find out more, read our illustrated article on the subject: 📘 What is the budget and the carbon footprint?

Today, it's difficult to project ourselves into imaginaries of low-carbon lives. It's almost the opposite of the model of society we've been defending up to now. And we are paying the price, both individually and collectively.

How can we imagine an annual footprint of 2 tonnes when societal services already burden us with 1.6 tonnes? Through collective action and political involvement, the aim is for these societal services to also decrease over time, which should make the target more attainable.

On the other hand... Walking in nature, playing music, cycling, sailing, taking the train all over the country, spending time with loved ones, celebrating, reading, chatting, gardening, learning to cook... A low-carbon life is full of joyful experiences, which are not necessarily reflected in an individual carbon footprint, but which will be at the heart of the lifestyles we are inventing right now.

The footprint displayed at the start of the test, before you have answered the questions, should be seen as a starting point. Throughout the simulator, you can compare the footprint of your consumption items (car mileage, heating, etc.) with values that are intended to be as close as possible to the French average.

This starting point is different from 8.9 tonnes of CO₂ₑ, the latest average French carbon footprint calculated by the Ministry of the Environment in November 2022.

This difference is normal, as the two calculation methods are very different:

• "From above ": The Ministry's average includes the carbon impact of all activities in the French economy, which it then divides by the 67 million French people.
• Bottom-up ": Nos Gestes Climat proposes adding, item by item, the footprints of all our actual and "significant" consumption (i.e. representing the vast majority of an individual's carbon footprint). The model is not exhaustive, the challenge being to strike the right balance between accuracy/completeness and complexity/test duration.

As long as the order of magnitude is identical, all is well (here we have a deviation of less than one tonne, i.e. less than 10%, which seems reasonable).

In addition, we're constantly looking to make the model more accurate and complete</a>. If you feel you've missed an important topic, please let us know on Github!

This item represents the carbon footprint of French public services, as well as a set of "basic" services that are difficult to avoid, brought down to an individual scale. In other words, the impact of all these services is spread over the 67 million French people.

🔎 Read our blog post "The footprint of societal services" to find out more.

So, in a way, everyone takes "their share", and for several reasons.

Firstly, it's extremely rare if not nearly impossible to live without ever using a single public service. Whether we're talking about health services, improved roads, education or, more generally, anything else funded by taxes, everyone benefits from public services. What's more, these services and their funding are voted on each year by the Assembly and defined by a regularly elected government.

Secondly, trying to account for the share of public services that an individual uses "for real" is not currently possible with the data we have on the footprint of this sector. Which doesn't mean we can't think about "variabilizing" the societal services item according to the individual's footprint!

In fact, it can be frustrating to have to account for impacts for which we have no direct leverage.

But that's the whole point of transition in the broadest sense

This transition cannot be thought of on an individual scale alone. It is a necessary but not sufficient condition for a more global transition on the scale of our society. This means playing with indirect levers of action (voting, associative involvement, raising awareness around us, etc.).

We've integrated some of these into the post-test action plan.

That's what Nos Gestes Climat is all about! Working to raise awareness of these issues!

No.

Nos Gestes Climat is dedicated to assessing individual carbon footprints. The trips you make in the course of your work (such as delivering a customer, going to a meeting, flying to attend a 3-day seminar, etc.) are not to be taken into account when answering the calculator's questions.

These journeys, which are part of your professional activity, will be included in the carbon footprint of your organisation (company, local authority, association, etc.). These are known as Greenhouse Gas Emission Balances (BEGES).

If you work for an airline and fly for personal reasons, the emissions of your flight will include those of the airline's employees.

**Why? Because, on a personal level, you have control over the type of transport you choose to use and where you live.

However, the reality is often quite different, and far be it from us to blame those whose daily mobility is centered around the car because they live far from their workplace. Even if certain choices can be questioned, many of us are, in fact, forced to use the individual car, for lack of serious alternatives available (public transport, telecommuting, carpooling, etc.).

As soon as you enter a car mileage greater than 0, the tool should "apply" to you a share of the depreciation on the construction of the car you're using.

Nevertheless, we are currently considering reducing the number of car-related questions asked of non-owners.

But what is depreciation?

The manufacture of a car is a far from trivial industrial process, contributing to the emission of several tons of CO₂ₑ. To avoid creating large variations in the footprint, particularly in the years when you buy a new vehicle, this impact is spread over the vehicle's lifetime. This makes it possible to compare your carbon footprint from year to year.

If you own your own car, the entire impact of construction is attributed to you. We ask how old your car is, to find out how much depreciation you still have to do. Nos Gestes Climat considers a car's depreciation period to be 10 years. Any older vehicle is therefore not considered (and automatically has zero emissions).

If you don't own your car, only a fraction of the impact of its manufacture is applied to your carbon footprint, in proportion to your use.

**On average, a car is stationary 95% of the time, so it's a good idea to share it!

The difference in footprint between different powertrains obviously lies in the use of the vehicle (fuel or electricity) via its consumption but above all in the associated manufacturing for each vehicle size.

As we don't directly consider a "footprint per kilometer " including vehicle manufacture and use (to guarantee greater customization), and in view of the very generic nature of the data from the carbon base on the footprint of car transport, we preferred to use theFNH-Carbone4 study: "What contribution can electric vehicles make to France's ecological transition?

This study gives us the manufacturing footprint of combustion, hybrid and electric vehicles for two sizes, the city car and the sedan. For the other sizes, we assign the same manufacturing footprint for city cars and medium-sized vehicles on the one hand, and for sedans, utility vehicles and SUVs on the other.

We could be even more precise by recalculating the footprint in proportion to vehicle weight.

We were surprised to see that the footprint of the hybrid sedan is smaller than that of the city car, but the study doesn't seem to explain this mystery.

Please note: eating organic does not, in itself, reduce your carbon footprint

To date, data indicates that for the same production and products, organic farming requires larger agricultural plots, reducing the size of forests and natural areas, which are essential for carbon sequestration. This is why, on a global scale and for equal quantities consumed, organic tends to be considered as having "more impact" on the climate than conventional agriculture.

Of course, this is no reason not to eat organic. This is a bias in our simulator. It only looks at carbon emissions.

And yet, from soil and groundwater pollution to loss of biodiversity and the preservation of farmers' health, an organic diet considerably reduces many other environmental impacts, while also reducing the risks to our health. We're dealing here with environmental issues in general, and need to take a step back from our 100% greenhouse gas-focused calculation.

There's a lively debate going on around this issue, and a lot of (digital) ink is being spilled on our Github. Feel free to join the conversation!

Nos Gestes Climat is, above all, a tool designed for the general public. That's why we wanted to limit the number of questions to the aspects of our food that we know to be the most important (impacting).

We know there's a lot missing from the current model. From self-produced food (chickens, vegetable gardens...) to insect-based dishes, the diversity of food practices is almost infinite!

Our tool is freely accessible, and we welcome contributions from everyone. So don't hesitate to send us your suggestions for improvement if you feel there's something missing from the model.

We'll explain how here.

Unless you have your own source of electricity (photovoltaic panels), the so-called "green" electricity supplied by renewable energy producers cannot be brought to you without the existence of the French electricity grid, a single network shared by all.

Nos Gestes Climat therefore uses only the emission factor of this network, which will be all the lower the more sustainable sources are connected to it. This emission factor is particularly low thanks to the high proportion of nuclear power and hydroelectric dams in our mix.

What's more, the figures provided by "green" electricity suppliers are theoretical, and, like all the figures in the Base Carbone®, have not been subject to technical consultation.

Nevertheless, subscribing to a "green" electricity contract is a good way of living up to our values, helping to create jobs that cannot be relocated, and sending a message to decision-makers in favor of the development of renewable energies.

As is the case for cars, depreciation is carried out for electronic products whose manufacture has a very high impact on the climate (notably because of the raw materials extraction phase).

We therefore ask you to provide the age of the product in order to determine the remaining depreciation period.

Assessing the impact of digital technology, and more specifically of "dematerialized" content (streaming, videoconferencing, cloud storage, e-mailing, etc.) is still a subject of work among technical and institutional players.

Our best estimate of the digital footprint is based on Base Carbone® data, but some information or questions may be missing.

🕹️ To find out more, test the impactco2.fr interactive simulator.

It's a common remark when it comes to assessing one's carbon footprint.

As the carbon weight of every product, good and service we consume does not yet exist, we have to approximate this impact. Here, we have to strike a balance between simplicity and precision.

As Nos Gestes Climat is a calculator for the general public, we've opted for simplicity.

This approximation is made by major product family. More concretely, the calculator is based on monetary ratios (X g of CO₂ₑ are emitted for Y € of products purchased), by product type, given by ADEME's Base Carbone®.

These monetary ratios enable the carbon content of a purchased product or service to be estimated from its price. For this purpose, a standard "average" product is considered. It does not take into account the specific features of less impacting products (second-hand, sustainable, eco-designed, etc.), which tend to increase the final footprint.

We have chosen to focus these questions on products purchased new, as the difference in impact with second-hand products is very significant. The production phase of the product, which very often represents the majority of impacts, is not taken into account for second-hand products. As for the differences in impact between new products (typically between fast-fashion jeans and eco-designed jeans), Nos Gestes Climat once again chooses to keep things simple.