ELECTRIC TRAINS – 100% CO₂-FREE?
Let me start by stating unambiguously: I am a vociferous supporter of train travel, which I see as one of the most environmentally friendly modes of transport. Nevertheless, the omnipresent marketing campaign by Slovenian Railways prompted me to take a closer look at their bold claim.
What are Slovenian Railways stating?
In their advertising materials, they state:
“Slovenian Railways make a significant contribution to environmental protection: from this year onwards, all electric trains run on electricity 100% generated from renewable energy sources, enabling us to provide carbon-free transport for passengers and freight.”
This statement is further supported on their website with carbon footprint calculations stemming from their Annual 2023 Report and data from the European Environment Agency:
- Passenger train: 0.031 kg CO₂e/PKM
- Freight train: 0.010 kg CO₂e/NTKM
- Private car: 0.1430 kg CO₂e/PKM
- Freight vehicle: 0.1400 kg CO₂e/NTKM
What do independent studies show (Planet Positive Event, 2025)?
- Passenger train: 0.0355 kg CO₂e/PKM
- Freight train: 0.02749 kg CO₂e/NTKM
- Private car: 0.1669 kg CO₂e/PKM
- Freight vehicle: 0.2493 kg CO₂e/NTKM
Comparative analysis:
Mode of transport | Data by Slovenian Railways (kg CO₂e/PKM) | PPE data (kg CO₂e/PKM) | Difference | Deviation (%) |
Passenger train (PKM) | 0.031 | 0.0355 | +0.0045 | +14.5% |
Freight train (NTKM) | 0.010 | 0.02749 | +0.0175 | +174.9% |
Private car (PKM) | 0.1430 | 0.1669 | +0.0239 | +16.7% |
Freight vehicle (NTKM) | 0.1400 | 0.2493 | +0.1093 | +78.1% |
What do these differences imply?
Slovenian Railways report a lower carbon footprint than the independent PPE source, particularly for freight trains and freight vehicles. The reasons for the noticeable differences might be:
- Methodology: Slovenian Railways considers the use of “green” electricity, whereas PPE takes into account average European emission factors (DEFRA).
- Calculation year: Slovenian Railways based its figures on actual data for 2023, while PPE used projected emission factors for 2025.
- Energy source: Slovenian Railways asserts that it uses 100% renewable electricity, which significantly reduces the calculated emissions.
Is this a realistic claim?
Yes, albeit with some important caveats. If Slovenian Railways can provide proof of supply contracts for electricity sourced from renewables with appropriate certificates (Guarantees of Origin), they are entitled to claim they use “green” electricity. That is fully aligned with EU legislation.
However, electricity flowing through the grid is always a mix of energy sources – fossil, nuclear, and renewable energy. Certificates merely verify that an equivalent quantity of green energy has been injected into the grid to match the consumption. That means Slovenian Railways de facto only reduce emissions on paper, within the framework of Scope 2 emissions.
Is this misleading or even greenwashing?
The answer is not straightforward. Slovenian Railways’ assertion that their trains are environmentally friendly or even CO₂-neutral is technically correct, as it is based on the trading system of green certificates. However, this approach does not reflect the actual consumption of electricity but the market logic of purchasing green certificates.
Whether such communication is fair and transparent should and must be evaluated in light of the forthcoming EU Green Claims Directive. Once in force, companies such as SŽ (and other companies making similar claims) will be required to comply with the following conditions:
- Substantiate claims with credible primary evidence.
- Obtain validation from an independent certified body.
- Publish the full supporting documentation, enabling both consumers and regulatory authorities to verify the claims.
Failure to comply with these requirements could result in fines of up to 4% of annual turnover and exclusion from public tenders.
Should Slovenian Railways wish to communicate credibly and justifiably that their trains are CO₂-neutral, they will need to conduct a detailed Life Cycle Assessment (LCA) of their electricity consumption and sources. They will also need to partner with third parties who will independently assess their data.
Perhaps they can take notes from the Swiss Federal Railways, which are leaders in this respect: https://company.sbb.ch/en/the-company/responsibility-society-environment/sustainability.html.
Recommendation:
For all those involved in sustainability communication, we strongly advise closely monitoring European legislation, as it will inevitably impact business practices soon. Some legislative proposals are still under consideration, whereas the CSRD and ESRS are already in effect and are reshaping reporting practices across the EU.
COM(2022) 143 final: Proposal for a Directive amending Directives 2005/29/EC and 2011/83/EU as regards empowering consumers for the green transition through better protection against unfair practices and better information. Available in English at: https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:52022PC0143
COM(2022) 672 final: Proposal for a Regulation of the European Parliament and of the Council establishing a Union certification framework for carbon removals. Available in English at: https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:52022PC0672
COM(2022) 71 final: Proposal for a Directive on Corporate Sustainability Due Diligence and amending Directive (EU) 2019/1937. Available in English at: https://eur-lex.europa.eu/legal-content/EN/ALL/?uri=CELEX:52022PC0071
Directive (EU) 2022/2464 – CSRD: Corporate Sustainability Reporting Directive (CSRD) https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:32022L2464
ESRS – European Sustainability Reporting Standards (Delegated Acts under CSRD):
Delegated Acts under CSRD https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:32023R2772
