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The Climate Score methodology

The Climate Score® is a simple, yet powerful tool, which enables the traveler’s decision-making on accommodation based on a score ranging from 1 to 10. The Score is easy understandable, but underneath it’s a well-documented scientific approach based on life cycle assessment principles.

The Climate Score® has been developed to cover “residing” at a hotel for 24 hours. This means that all activities and meals during a full day are included. In the method the guest is the central part of the calculation, which is also why the result of the assessment is given as the average kg CO2e per guest per 24 hours. The Climate Score® is a conversion of the CO2e emissions per guest per day.

The method is based on first calculating the total yearly CO2e emissions from the hotel. This is done by collecting all consumption data from the hotel and match it with the correct emission factors provided as CO2 equivalents

The consumption data from the hotels includes guest on-ground transportation to and from the hotel, energy, food and beverages, waste, water, hotel procurement, laundry and staff activities. The emission factors, which the consumption data is matched with, comes from commercial LCA databases, such as EcoInvent and EXIOBASE. This approach is similar as used when companies perform ESG reports.

The strength in Climate Score® is the calculation of emissions per guest, more specifically a guest who is arrives at the hotel and is present for 24 hours and has their three daily meals at the hotel. To reach this 24-hour guest equivalent Climate Score® accounts for different guest types, specifically overnight guest, conference guests and restaurant guests. Each guest type’s consumption is weighted and allocated differently depending on how each type utilizes the hotel services.

The allocation principle applied here is to account for variation in hotel operations based on guest types and their behavior at the hotel. This approach acknowledges that hotels, depending on their location and specialization, have distinct priorities in accommodating various types of guests, which has been categorized as restaurant guests, conference attendees, and leisure guests, as these are the ones responsible for most emissions. For city-based hotels, it is often essential to cater to overnight guests and restaurant guests equally (more so than conference guests). In contrast, conference hotels prioritize service for conference guests, and spa and leisure hotels focus on meeting the preferences and demands of leisure guests. This level of detail is what the uniqueness of the Climate Score® methodology. It is recognized that each guest has their own individual consumption and footprint, the values calculated is for an average guest based on the whole year.

The Climate Score® is reset yearly instill motivation for hotels to always improve as the best hotel will always be set as 10 and the worst as 1. The score exists as both a global score, meaning it is based on all hotels in the world, and a national score where only the hotels in the country are considered.

In 2023 the global score for all hotels were as follows:

The method described here is included in the full scientific methodology report which has been reviewed by three panel members from three international climate institutions. The Critical review process was completed in January 2024 to verify that the methodology adheres to ISO-14040 and ISO-14044. The full report with a more detailed calculation example for the Danish hotel industry can be found here: LINK

The Climate Score® methodology

The Climate Score® methodology accounts for almost all types of consumption which are part of the consumption in households. Therefore, the Climate Score® assessment (24h guest eq. CO2e-impact) can be compared to the emissions in households (citizen CO2e-impact). This indicative comparison serves to provide a reference when talking about emissions per person per day for the average traveler to understand.
When comparing these emissions, to ensure that the material and energy that flows into the two systems fulfills the need for reasonable completeness, it is necessary to be aware of a list of industries and sectors that contribute to national emissions which are not included in the Climate Score® methodology. This includes societal emissions, such as hospitals, the educational system etc. and all air and water transportation methods, which are not included in the Climate Score® methodology. This is illustrated in the figure and must be explained and kept in mind when communicating this comparison.

For Denmark alone, various estimates of emissions from the average Danish citizen’s consumption abound. One report pegs the emission at 11 tons of CO2e per person per year, while another suggests it’s 19 tons per year. The latest report from Concito, employing Exiobase, estimates the average Dane emits 13 tons of CO2e annually. Despite different years in these reports, the results and methodologies significantly vary. The challenge lies in identifying a method and data source that closely aligns with the system boundaries of the Climate Score®. The method most comparable across countries, while promoting transparency, is Exiobase. “EXIOBASE is a global, detailed Multi-Regional Environmentally Extended Supply-Use Table (MR-SUT) and Input-Output Table (MR-IOT)”

To compare a guest’s emissions at a specific hotel using the Climate Score® methodology against the average citizen’s emissions, we identify emission categories excluded from the Climate Score®. Subtracting these from the average citizen’s emissions allows us to assess whether a guest emits more or less CO2e compared to the average citizen when evaluated using the Climate Score® methodology. Using Exiobase, all consumption-related emissions in Denmark equal 73 MtCO2e (33.9 kg CO2e per Dane per day). Examining the industries and sectors affecting a Dane’s emissions, 79% of total Danish consumption is covered by industries emitting more than 0.12 MtCO2e, our threshold value.

Adjusting the threshold value for other countries based on when more than 75% of all emissions are covered, we find that 10.63 MtCO2e of the 73.86 MtCO2e in Denmark originates from industries not included in the Climate Score® methodology.

As a result, when removing categories from relevant industries and sectors, emissions for Denmark within the Climate Score® methodology are 63.23 MtCO2e (29.6 kg CO2e per Dane per day), including the construction of buildings in the value chain, such as factories and plants, which contribute to emission factors for all hotel input data, even though the hotel building’s construction itself is not part of the methodology.

This figure can be compared to the CO2e-impact assessment using the Climate Score® methodology. While the comparison is the best possible, it’s important to note its limitations, as most of the Climate Score® impact relies on primary physical and financial data, with Exiobase emission factors used marginally. It serves as a benchmark or reference to communicate the impact to the public, with no claims made in terms of percentages or similar without referencing the methodology description. However, it’s crucial to be aware that the comparison only considers a 24-hour stay at the specific hotel with on-ground transportation, excluding flights or other societal impacts. Thus, it provides no indication of the total emissions for a tourist’s emissions in general.

While other sources and methods may offer alternative comparisons and emission figures for households, this choice is made for transparency, given that Exiobase data is publicly available.

Method adheres to ISO-14040 and ISO-14044

The method described here is included in the full scientific methodology report which has been reviewed by three panel members from Danish Technological Institute, Quantis and Global Footprint Network institutions. The Critical review process was completed in January 2024 and concluded that the methodology adheres to ISO-14040 and ISO-14044.

The Climate Score® is consistent with ISO 14040/14044 and good LCA practice. It is scientifically and technically valid and transparently reported according to the review panel with Danish Technological Institute, Global Footprint Network and Quantis. The full report with a more detailed calculation example for the Danish hotel industry can be found by clicking on the bottons below.