FAQ on Footprints and climate neutrality:


What causes global warming?

Climate change is caused by the greenhouse effect: Greenhouse gases in the Earth's atmosphere allow solar heat to enter the atmosphere, but hinder its radiation back into space. Many of these gases are natural components of the Earth's atmosphere. However, human activity has greatly increased the concentration of some greenhouse gases. CO2 is the greenhouse gas that is produced most by human activities in terms of quantity: 63% of the global warming caused by humans is attributed to it.

The CO2 concentration in the atmosphere is 40% higher today than at the beginning of industrialisation. Other greenhouse gases are also emitted in smaller quantities, but they hinder the radiation of solar heat back into the universe thousands of times more effectively than CO2 . 19% of man-made global warming is due to the greenhouse gas methane (CH4 ), 6% to nitrous oxide (N2 O). Fluorinated gases account for most of the rest. The amount of greenhouse gases naturally occurring in the atmosphere is increasing enormously, mainly due to the use of fossil fuels, deforestation of rainforests and livestock farming.

Why is climate change a serious problem?

Rising average temperatures and steadily rising sea levels are just two of the many impacts of climate change. It leads to a change in climate variability - strong short-term climate fluctuations and more frequent extreme weather events such as heavy rain or hot summers are the result.

Particularly threatening risks are the reduced quality and quantity of drinking water and growing conditions for staple foods. The changed or prolonged occurrence of biological allergens (e.g. pollen) and the increased occurrence of so-called vectors (disease vectors such as ticks or mosquitoes) are also cause for concern. The shift in the periods in which plants grow, flower and bear fruit also has an impact on agricultural production.

The economy and transport are also affected: Roads and railways are washed out by heavy rain and suffer from high temperatures, inland waterways suffer from high or low water. In addition, many power plants draw their cooling water from rivers and feed it back in heated: If the river water is too warm or severely depleted by summer heat, power plants have to be shut down in an emergency.

What does climate neutrality mean? What is the difference between CO2 -neutral and climate neutral?

Climate neutrality is the state of equilibrium between the emission of carbon and its absorption from the atmosphere in so-called carbon sinks. This means that climate neutrality is achieved when no greenhouse gases are emitted in excess of those that can be absorbed by nature or other sinks.

In addition to greenhouse gases, however, other indicators of global warming also play a role, such as soil and water contamination, raw material consumption and biodiversity. Looking at all environmental impacts is indispensable for the climate, but it is very complex and requires a lot of effort.

Therefore, in line with the United Nations Framework Convention on Climate Change, the focus is initially on the first step towards climate neutrality: greenhouse gases (CO2 neutrality). However, in order to create binding definitions and statements on climate neutrality, the ISO 14068 standard is currently being developed at the international level - until now, climate neutrality has usually been assessed on the basis of PAS 2060.

What is the Global Warming Potential (GWP) and what do CO2 equivalents (CO2e) mean?

When drawing up greenhouse gas balances (carbon footprints), as the name suggests, not only carbon dioxide but also other climate-damaging gases (greenhouse gases) are considered. These climate-relevant gases were defined in the Kyoto Protocol and assessed annually by the Intergovernmental Panel on Climate Change (IPCC).

In addition to CO2 , gases such as methane (CH4 ), which is mainly released by agriculture and gas leaks, are also included in the balance. Also included are various coolants, nitrous oxide (N2 O) from fertilisers and the chemical industry, and sulphur hexafluoride (SF6 ), which is used as an insulating gas in high-voltage technology.

All of these additional gases have a significantly greater impact on the climate than CO2 . In order to be able to compare the relevance of the gases more clearly, the so-called "Global Warming Potential" (GWP) was defined.

The GWP of methane, based on the effect over 100 years, has the value 28. This means that the effect on the climate of 1 t of methane is just as damaging as that of 28th of CO2 . Partially halogenated or perfluorinated hydrocarbons in particular often have four-digit GWP values. The scale goes up to SF6 with a GWP of 23,500.

In order to be able to present carbon footprints in a comparable way, the total amount of greenhouse gas emissions is therefore also stated in so-called CO2 equivalents (CO2 e) in addition to the breakdown into the individual gases. Here, non-CO2 greenhouse gases are converted into CO2 e via their GWP.
An example illustrates this:

If a company had annual emissions of 100 t CO2 and 1 t CH4 , the company's carbon footprint would be 128 t CO2e.

Which sectors are particularly affected?

Responsibility for environmental protection affects all industries. However, emission-intensive -sectors such as energy production or heavy industry (steel, aluminium, etc.), for which concrete measures have already been defined in the climate package, play a special role. The ¬focus is also on companies whose products are delivered directly to end consumers (B2C), such as food or car manufacturers and the public sector. The food industry and trade in particular can no longer avoid the topic of greenhouse gas balancing and climate neutrality.

In the B2B sector, climate neutrality is playing an increasingly important role in the awarding of contracts; in the B2C sector, it can influence the public image, sales figures and thus market shares. As an affected company, you can find more information here.

How much is one tonne of CO2?

The carbon footprint is indicated by the amount of CO2 e in tonnes. But how can you imagine a tonne of CO2 ? Here are a few examples:

  • Driving 9500 km with one car
  • heat an average flat for 2 months
  • a flight for one person from Brussels to Marrakech
    (~ 2350 km)
  • The amount of CO2 that a beech tree binds in about 80 years of growth
  • The volume of a cube made of one gaseous tonne of CO2 would have an edge length of eight metres under normal conditions


What are the so-called scopes?

Greenhouse gas sources are divided into three so-called "scopes" according to the Greenhouse Gas Protocol. The scopes are used in the greenhouse gas balancing of companies (corporate carbon footprints). When balancing products, the life cycle stages are considered.

Scope 1 includes all greenhouse gas emissions that occur directly in the company, i.e. emissions from the combustion of stationary sources (e.g. boilers), emissions from the combustion of mobile sources, e.g. from the company's own vehicle fleet, emissions from the company's production processes and fugitive emissions (especially coolants).

Scope 2 includes only the indirect emissions that arise for the energy supply of a company A. This means that all those emissions are included here. This means that all those emissions are calculated here that arise when an energy supplier B provides electricity, natural gas or district heating for company A.

Scope 3 includes the remaining emissions from upstream and downstream supply chains that are related to the company's activities. This includes, for example, emissions from purchased goods and services, waste treatment, business travel, commuting and product use. If the company produces petrol or diesel, for example, the emissions that are ultimately generated by the customer's use of these fuels are calculated here. The Greenhouse Gas Protocol divides Scope 3 emissions into 15 categories.

What are indirect greenhouse gas emissions (Scope 3) and which ones need to be taken into account?

Scope 3 emissions are a consequence of the company's activities along the value chain. However, they arise from sources that are not owned or controlled by the company. In the GHG Protocol, these activities are divided into upstream and downstream processes and comprise 15 categories:


  • goods and services purchased
  • Capital goods
  • Fuel and energy-related activities (not Scope 1 or 2)
  • Upstream transport and distribution
  • Waste generated in the operation/process
  • Business trips
  • Shuttle
  • Upstream leased assets


  • Downstream transport and distribution
  • Processing of the products sold
  • Use of the products sold
  • End-of-life treatment of sold products (disposal/recycling)
  • Downstream leased assets
  • Concessions
  • Investments

Scope 1 and 2 emissions must be determined in accordance with ISO 14064-1 and GHG. Scope 3 emissions must be assessed and considered in terms of their materiality. According to PAS 2060, all greenhouse gases must be included and converted into t CO2 e. This concerns 100% of all Scope 1 and 2 emissions. Scope 3 emissions that account for more than 1% of total emissions must also be reported. If emissions are estimated, it must be excluded that underestimations occur. The carbon footprint must include at least 95% of all emissions.

Which greenhouse gases need to be taken into account? What do upstream chains and CO2 e mean?

According to ISO 14064, the organisation must report the quantities of direct greenhouse gases (GHG) by type of gas separately in tonnes of CO2e (CO2 equivalents). Relevant gases are CO2 (carbon dioxide), CH4 (methane), N2O (nitrous oxide), NF3 (nitrogen trifluoride), SF6 (sulphur hexafluoride) and other appropriate GHG groups such as HFCs (hydrofluorocarbons), PFCs (perfluorocarbons), etc. The CO2 e indicates the global warming potential, i.e. the factor by which a greenhouse gas contributes to global warming compared to the same mass of CO2 .

Emission factors used to calculate the carbon footprint are available without and, in the best case, with "upstream chains". With upstream chains means that they include emissions from upstream and downstream processes. For example, the emission factor for diesel without upstream chain only includes the direct emissions from the combustion of the fuel. The emission factor with upstream chain additionally includes emissions that occur during the extraction of the raw material, refining and through supply.

Where can I get reliable emission factors?

When selecting emission factors and databases, it should be noted that some factors include upstream chains and thus the production process ¬(extraction, processing and transport, sometimes even including the construction of conveyor systems). Others include only the direct combustion of the substance. Here is a list of reputable databases (excerpt):

  • GEMIS (free of charge, values for energy, material and transport systems)
  • ecoinvent (fee-based, one of the best-known services)
  • ProBas (free, with life cycle data, from UBA and Öko-Institut)
  • EFDB (fee required, English, contains emission factors of the Intergovernmental Panel on Climate Change (IPCC))
  • Emission Factor Database (free, English, from various sources)
  • Greenhouse Gas Protocol (free, English)
  • DBEIS (ex-DEFRA; free, English, some data UK-specific).

Calculation tools:

How must electricity be balanced?

For the accounting of purchased electrical energy, the Greenhouse Gas Protocol and ISO 14064-1 (and ISO 14067) require greenhouse gas emissions to be calculated using so-called site- and market-based emission factors.

  1. Market-based method:
    In this approach, emissions from electricity generators from which the reporting party purchases electricity under contract are taken into account. This also includes electricity characteristics from contracted resources, such as guarantees of origin, purchased by the generator or the reporter itself.

  2. Location-based method:
    In this approach, the emission quantity is described that best reflects the emissions of the regional grid and corresponding electricity producers. For companies in the German region, we recommend using the values of the Federal Environment Agency here.

In a standard-compliant greenhouse gas report, both approaches should be used, so that two different values and an overall balance result for Scope 2. The same requirements apply to the balancing of the other Scope 2 categories such as natural gas purchases, steam purchases, district heating, district cooling and other energy sources.
To the original source of the reply

Which electricity mix do I have to use? What is a residual mix?

An emission factor for electricity is intended to reflect the emissions from electricity consumption. The balanced emissions of the electricity consumed are not necessarily the same as those generated during production. According to §42 EnWG, every electricity supplier has a so-called electricity labelling obligation¬. This corresponds to the market-based approach. According to this, the environmental impact must also be shown in ¬g CO2 /kWh. The "residual mix" adjusts the production mix in such a way that the emissions of imported and exported electricity quantities are included in the balance and thus the guarantees of origin are ¬taken into account. Further information on the residual mix can be found at the association of issuing bodies (AIB).

How are emissions from leased/rented facilities, rooms and vehicles handled?

In order to correctly allocate emissions from leased assets, it is first necessary to define the organisation's consolidation approach and allocate the type of leasing. Leasing can be divided into two categories.

1. Finance/capital leasing:
This type of lease transfers all risks and rewards associated with ownership of the asset to the lessee. Assets leased under a finance lease are considered wholly owned in financial accounting and are reported as such in the balance sheet.

2. Operating leasing:
This type of lease allows the lessee to operate an asset, such as a building or a vehicle. However, none of the risks or rewards incidental to ownership of the asset are transferred to the lessee. Any lease that is not a financial or capital lease is an operating lease. An example here is leased vehicles in particular.

Depending on the consolidation approach, the emissions must then be allocated according to Scope 1,2 or 3. This results in four cases:

A. Consolidation approach "financial control or equity share approach and financial leasing":
In this case, the leased assets are treated as own capital assets. Direct emissions from operations are accounted for in Scope 1, energy-related emissions in Scope 2.

B. Consolidation approach "financial control or equity share approach and operating leases":
There is no financial control or ownership of the leased asset. Direct and energy-related indirect emissions from operations are to be fully accounted for in Scope 3.

C. Consolidation approach "operational control and financial leasing":
Since leased goods are to be treated as own capital goods in the case of financial leasing and thus fall under operational control, direct emissions from operations are accounted for in Scope 1, energy-related emissions in Scope 2.

D. Consolidation approach "operational control and operational leasing":
The lessee has operational control over the asset, therefore direct emissions from operations fall under Scope 1, energy-related emissions in Scope 2.

To the original source of the response

What is the significance and influence of GHG offsets for my carbon footprint and climate neutrality strategy?

In the standards, compensation of unavoidable greenhouse gases is required or can be optionally included in the carbon footprint. In general, it should be noted that the sequence of balancing, reducing and offsetting must be followed for all standards. First and foremost, greenhouse gas emissions must be reduced through active reduction measures within the organisational boundaries before compensatory measures are taken.

Reliable offsets have become a serious issue following reports of fraud and abuse related to carbon accounting. It is therefore crucial to ensure that offsets actually deliver the desired environmental benefits. The use of low-quality offset certificates can also have a significant impact on reputation (greenwashing). Various standards have been developed to assess offset quality. On the website of the Federal Environment Agency there is a detailed guide on this topic.


According to which standards can a greenhouse gas balance be drawn up and verified?

Corporate Carbon Footprint

  • DIN EN ISO 14064-1 "Specification with guidance for the quantitative determination and reporting of greenhouse gas emissions at the organisation level".
  • Greenhouse Gas Protocol: A Corporate Accounting and Reporting Standard
  • Greenhouse Gas Protocol: "Corporate Value Chain (Scope 3) Accounting and Reporting Standard".

Product Carbon Footprint

  • ISO 14067: Carbon footprint of products - Requirements and guidelines for quantification and communication
  • Greenhouse Gas Protocol: "Product Life Cycle Accounting and Reporting Standard"
  • PAS 2050: Publicly available specification vom BSI (British Standards Institution) How to assess the carbon footprint of goods and services

Climate neutrality

PAS 2060: Publicly available specification vom BSI (British Standards Institution) Specification for the demonstration of carbon neutrality

Project Footprint

ISO 14064-2 Carbon footprinting of projects - Principles and requirements

What are the advantages of verifying the carbon footprint according to a standard?

The standards that can currently be certified are internationally recognised standard protocols according to which a carbon footprint or climate neutrality strategy can be developed. Once your organisation has been verified according to an appropriate standard, it is freely visible and openly comprehensible to everyone how and according to which criteria your carbon footprint or climate strategy was prepared. Findings from the Carbon Footprint can be communicated transparently and easily to the outside world.


What are the advantages of drawing up a greenhouse gas balance and verifying it?

A carbon footprint serves as a management tool for implementing CO2 and cost reduction plans and developing a clear climate strategy to help mitigate global warming.

External verification of the GHG balance secures reporting, improves reputation and serves as proof of the credibility of your climate neutrality.

Should the carbon footprint be used for comparison with other products or organisations?

The current primary objective of Carbon Footprints is to identify potential savings. In addition, it should enable your organisation to develop a reduction plan and to document and communicate the reduction progress according to international standards.
Optionally, or when developing a climate neutrality strategy, emissions can be offset accordingly.

Comparison between products is discouraged according to the current state of the standards. The regulations on data collection allow the use of primary and secondary data, depending on whether direct emission measurement is technically feasible and reasonable in terms of price. Due to the different data basis, there can therefore be considerable deviations when creating a carbon footprint for one and the same reference unit, depending on the collection method.

Especially in the case of greenhouse gas balancing of products, we currently strongly advise against comparative communication of the results. The product carbon footprint standard ISO 14067 sets clear and strict requirements for comparative statements (ISO 14025 as the basis for environmental product declarations). If it cannot be ensured that exactly the same balance limits and data basis have been used, no comparative communication may be made.

What is a Carbon Handprint?

A carbon handprint calculates the positive greenhouse gas impact achieved through an active improvement over a certain baseline. This can be achieved, for example, by improving a customer's performance.

The concept can be used for marketing and communication purposes - you can communicate on your latest improvement or highlight the climate benefits of your products and services.