Do you know the carbon footprint of your dialysis facility?

We, GreenTec Dialysis GmbH, developed this CO₂ -calculator specifically for dialysis facilities under the patronage of the “Kidney and Environment” commission of the German Society of Nephrology (DGfN).

The data from all dialysis centres in Germany are being compiled in a study. This allows us to first assess the current status of dialysis. How does dialysis treatment compare with other areas of the healthcare system? What are the main sources of greenhouse gas emissions in the dialysis process? How do the data from Germany compare internationally? Where can potential for improvement be identified?

The answers to these questions form the basis for the development and implementation of measures to reduce greenhouse gas emissions and thus also to lower operating costs.

First, it is essential to determine where your dialysis centre currently stands in terms of its environmental footprint. Using this data, you can take targeted measures to improve your dialysis’ environmental footprint, while reducing operating costs.

There are recognised standards for the calculation of the CO₂ footprint. The calculator we developed is based on the reporting standard of the Greenhouse Gas Protocol (GHG).

The GHG Protocol divides emissions into three categories: Scope 1, Scope 2 and Scope 3. We collected data across all three scopes.

The accounting period covers a full calendar year. For the calculation of greenhouse gas emissions, values from January 1 to December 31 of the respective year are used.

The data and equivalent values used in the calculations come from established and recognised databases (Ecoinvent) and sources (Bavarian State Office for the Environment (LfU), Federal Environment Agency (UBA)). The data is always kept up to date.

The basis for the design of the CO_2-eq footprint calculator for dialysis centres is the Greenhouse Gas Protocol (GHG) reporting standards. All relevant emission sources under Scope 1 and 2, and optionally Scope 3, are queried.
For many processes not under the direct operational control of the dialysis provider (Scope 3), data is still unavailable or not publicly accessible (e.g. greenhouse gas emissions from the production of dialysis machines or pharmaceuticals).

Therefore, certain system boundaries must be defined when developing a CO_2-eq calculator. Only within these predefined system boundaries is a reliable, data-driven calculation possible using actual, currently available data. With identical system boundaries and accounting periods, benchmarking between different centres is possible.

The most abundant greenhouse gas released by humans in terms of quantity and overall impact on global warming is carbon dioxide (CO₂). That’s why the term CO₂ footprint or carbon footprint is often used, even though all greenhouse gases are included. To avoid misunderstandings, it is more accurate to refer to “carbon dioxide equivalent” (CO_2-eq) when other greenhouse gases are included in the footprint calculation. CO₂-equivalents (CO_2-eq) are a unit of measurement to standardise different greenhouse gases.

Greenhouse gases are gases in the atmosphere that have an impact on the Earth’s energy balance. They are responsible for the so-called greenhouse effect. In 1997, the Kyoto Protocol established a legally binding international agreement to reduce anthropogenic emissions of key greenhouse gases.

The best-known greenhouse gas is carbon dioxide (CO₂). Other gases, such as methane (CH₄), nitrous oxide (N₂O), hydrofluorocarbons (HFCs / HFCs), perfluorocarbons (PFCs), sulphur hexfluoride (SF6) and, since 2012, nitrogen trifluoride (NF₃) also contribute to the greenhouse effect. These greenhouse gases are regulated under the Kyoto Protocol.

The concentration of greenhouse gases is subject to natural fluctuations (temperature, etc.). Due to human activity, the concentration of gases has increased significantly in recent years.

Standardised methods are used to calculate greenhouse gas emissions. The goal is to use activity data, such as electricity consumption, to calculate the CO₂-emissions. The calculation is carried out by multiplying activity data by defined emission factors.

The Greenhouse Gas Protocol, also known as the GHG Protocol, is the most widely used standard for preparing greenhouse gas inventories. It is a globally standardised reference framework for measuring and controlling greenhouse gas emissions, across both the private and public sectors, for value chains, and initiatives aimed at reducing carbon emissions.

It was introduced in the 1990s by the World Resources Institute (WRI) and the World Business Council for Sustainable Development (WBCSD) and has been continuously developed ever since.

The international Ecoinvent database is currently the world’s leading source for life cycle assessment data, with over 2500 users in more than 40 countries. As the most consistent and transparent life cycle inventory database, it supports environmental assessments of products and processes worldwide.

The accounting period covers greenhouse gas emissions (GHG) for one full year, starting on January 1 and ending on December 31 of the same calendar year.

When creating a corporate carbon footprint and the corresponding reporting system, five fundamental principles must be observed:

• Relevance: It must be ensured that the system boundaries and the company’s GHG balance appropriately reflect reality.
• Completeness: All emission sources and activities within the defined system boundary must be included in the reporting.
• Consistency: The use of consistent methodologies is a prerequisite for comparing emissions over a longer period of time.
• Accuracy: It must be ensured that the quantification of GHG emissions is neither systematically over- nor underestimated (as far as can be judged). Any uncertainties must be reduced as much as possible.
• Transparency: All relevant information must be presented in a factual, objective and comprehensible manner and must be verifiable.

The Greenhouse Gas (GHG) Protocol distinguishes between three categories, known as “scopes”, to differentiate between different emission sources.

Scope 1: This category includes all CO₂ emissions that can be directly controlled by the reporting organisation (direct CO₂-emissions). This includes the combustion of fossil fuels (mobile and stationary), emissions from chemical and physical processes, and refrigerant leaks from air conditioning systems.

Scope 2: This category includes indirect CO₂ emissions caused by the combustion of fossil fuels during the generation of electricity, heat, cooling and steam by external energy suppliers.

Scope 3: All other CO₂ emissions that fall outside the company’s or organisation’s direct control are categorized under Scope 3 (other indirect emissions). This includes emissions related to the production, use, or processing of goods and services purchased by the company, as well as emissions generated from the use of sold products and services are included, if such use results in direct CO₂ emissions.

The corporate carbon footprint is a company-level approach to greenhouse gas accounting. It considers both direct and indirect greenhouse gas emissions along a company’s value chain within a defined time frame.

The term “system boundary” in the context of life cycle assessment (LCA) is a tool used to clearly define the scope of the system under study and to distinguish it from its environment.
Before any calculations are made, the scope of the assessment must therefore be clearly defined.

There are organisational and operational system boundaries.

The organisational system boundaries refer to the organisational unit and the time period to which the CO_2-eq footprint applies. Greenhouse gas emissions are recorded and analyzed for each individual dialysis center. If multiple centers are part of a shared organization, the CO_2-eq footprint can be calculated separately for each center. However, it is also possible to calculate a combined footprint for all affiliated centers.

The operational system boundaries define the emission sources considered within the organisational boundary. The operational system boundaries are based on the framework of the Greenhouse Gas Protocol. The relevant categories for the healthcare sector according to the ADEME guidelines (Agence de la transition ecologique, a leading authority in climate accounting in the healthcare sector) are taken into account.

The greenhouse gas potentials published by the Intergovernmental Panel on Climate Change (IPCC) are generally recognized as standard.
They are provided for different time horizons — 20, 100, and 500 years — reflecting the varying atmospheric lifetimes of the gases.

The Greenhouse Gas Protocol (GHG) Product Standard uses a time horizon of 100 years. Emission calculations (expressed as carbon dioxide equivalents, CO₂-eq) are therefore based on the Global Warming Potential (GWP).

The GWP indicates the extent of warming a gas causes over a specific period of time.
Global Warming Potential 100 (GWP 100) refers to the warming effect of a gas over a 100-year time frame.