Become a part of the 2zero community

From small communities to large districts – with the 2zero app, you reach your citizens and create a strong sense of community around climate protection

NDR feature on the major Climathon in Schleswig-Holstein 2025

The Climathon competition runs for 42 days in Schleswig-Holstein. The "2zero" app shows how much CO₂ is produced by certain activities and how much can be saved.

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Erfolgsstory Lüneburg

Die Klimaschutzmanagerinnen der Hansestadt Lüneburg berichten über ihren Klimathon 2024 mit 2zero.

Karina Hellmann

Hansestadt Lüneburg

Juliane Ette

Hansestadt Lüneburg

Erfolgsstory Schleswig-Holstein

Die Klimaschutzmanager:innen von Kiel und Flensburg berichten über ihre Erfahrungen mit 2zero während des gemeinsamen Klimathons im März 2023

Carina Knebel

Stadt Kiel

Andreas Oeding

Stadt Flensburg

1 year of sustainable change: The city of Asperg and 2zero

To gain insight into the city's progress, we spoke with Stephanie Owerfeldt, the municipal climate protection officer for the city of Asperg.

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Experience report from Lüneburg: Our journey through the Climathon

Insights into the motivation, effort, and collaboration with 2zero during the Climathon of the Hanseatic City of Lüneburg!

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From successes to new goals: Climathons in Schleswig-Holstein

The annual Climathons by 2zero in Schleswig-Holstein are excellent examples of how local engagement and sustainability can go hand in hand.

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Sustainability funding program: LEADER supports the 2zero annual membership

Thanks to the LEADER funding program, the municipality of Ostercappeln has made significant progress toward sustainability with 2zero. The application process went smoothly.

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Kassel's new climate protection app: How klimo is making Kassel more sustainable

The regional app klimo promotes low-emission behavior in Kassel, highlights various options, and rewards climate-friendly actions. In doing so, the app raises awareness for climate protection.

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Verl's Perspective: A Look Back at the Climathon

Find out in this case study what local climate protection can look like – The Climathon in action in Verl!

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A look back at the first Climathon

Climathon 2020 in Oberursel in the Taunus region: 46,000 residents were called upon to protect the climate together. A look back at the very first Climathon and the perspective at the time.

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The 2zero track record

>60

municipalities have carried out a climate protection campaign with 2zero

>23.000

citizens have participated in the campaigns

>182.000

participants have completed challenges along the way

Here’s what other climate protection managers are saying

"With 2zero, we’re giving another boost to our EU Mission “100 Climate-Neutral Cities” pilot project CoLAB. This allows us to motivate citizens with changing challenges for a sustainable everyday life, helping them playfully move from knowledge to action.“

Agnes Schönfelder

City of Mannheim

"Communication with 2zero was perfect, problems were promptly discussed and resolved, and a competent team member was always there to provide support"

Dr. Lisa Rütgers

Climate Protection Manager of the District of Ebersberg

"The 2zero support team is very accommodating, innovative, thoughtful, and helpful. We had numerous specific requests for changes in Lüneburg, and almost all of them were implemented promptly."

Karina Hellmann

Climate Protection Manager of the Hanseatic City of Lüneburg

"The Climathon showed us that the 2zero app simplifies communication and clearly illustrates how much CO₂ was saved together. Definitely recommendable for other municipalities!"

Anna-Lena Enskat

City of Duderstadt

"The Climathon showed us that the 2zero app simplifies communication and clearly illustrates how much CO₂ was saved together. Definitely recommendable for other municipalities!"

Fabian Humpert

Climate Protection Manager of the City of Verl

"The diverse range of climate-friendly behavior measures makes the 2zero app an innovative climate protection tool for behavior-oriented climate action."

Andreas Oeding

PR Manager of the Climate Pact Flensburg

"The Climathon offers us as a municipality a great opportunity to engage with different target groups. The content is very informative and easy to understand."

Lisa Macheleidt

Climate Protection Manager of the State Capital Kiel

"We intensively promoted the 2zero app on social media in advance using the provided materials and were able to achieve a great number of participants as a result."