By Sabrina Hoffmann and Viktoria Reith, Climate Strategy Office, City of Mannheim


Characterised by its proximity to two rivers, the Rhine and the Neckar, as well as its heavy industry, the City of Mannheim in south-western Germany faces an urgent climate challenge. The city has committed to becoming climate neutral by 2050 and is looking into whether this goal can be achieved even sooner. The City of Mannheim is taking on this task, for example, with its Climate Action Plan 2030, climate impact adaptation measures and the provision of funding in cooperation with the Climate Action Agency. Together, they offer consultation, subsidies and a newly created City Lab where residents can get involved in the decision-making process.

The status quo

Currently, Mannheim is facing several challenges to reduce its emissions: Its coal-fired power plant Grosskraftwerk Mannheim (GKM) supplies not only the city’s 320,000 residents, but also those of neighbouring cities – a total of 2.5 million households receive power from the plant and 160,000 are connected to its district heat system. Furthermore, Mannheim is characterized by heavy industry, with high energy use that needs to be decreased for realistic chances of achieving climate neutrality.

The river Neckar flowing through Mannheim. Credit: Stadtmarketing Mannheim GmbH, Daniel Lukac

Still, the projections are promising: a recent study by the Wuppertal Institute found that Mannheim can reduce its energy-related CO2 emissions by 99% by 2050 compared to today’s levels and thus meet the targets of the Paris Climate Agreement at the municipal level. The largest share of this reduction would be achieved by decommissioning the GKM by 2033. There is realistic potential for generating almost 1 TWh of green electricity within the city limits, mainly solar energy supported by river heat pumps, waste-fuelled as well as biomass heating and power plants, and wind generators. This means the city would shift from being a net exporter of electricity to being a net importer.

Mannheim’s Climate Action Agency

In cooperation with the City of Mannheim, the Climate Action Agency provides free advice on energy and climate protection issues. Residents can approach the agency for five different types of checks:

  • The basic check looks at electricity and heat consumption in the household.
  • The building check also covers the cladding and heating technology.
  • The heating check examines possible improvements to the existing heating system.
  • The solar check looks at whether the building is suitable for the installation of a photovoltaic system.
  • The greening check explores different measures for homeowners to make their buildings greener.

The Climate Action Agency also manages the city-financed funding programmes and provides advice on how to get funding from municipal, national and EU sources. For example, the City of Mannheim supports the installation of a new photovoltaic system with a SolarBonus of €120 kilowatt peak of installed capacity, up to a maximum of €1,200 per system, and awards additional grants for storage tanks and tax advisor fees.

Social innovation in the City Lab

Together with ICLEI – Local Governments for Sustainability, Mannheim is one of six cities participating in the EU project SONNET (Social Innovation in Energy Transitions). Social innovations start by changing social relationships. To research how social innovations can support the energy transition, Mannheim established a City Lab to develop and test new organizational governance and participation processes. The City Lab provides a space for local stakeholders such as the District Management, the Consumer Center, businesses, local associations and citizens to connect, participate in decision-making processes and receive support from the City of Mannheim.

SONNET neighbourhood talk in December 2020. Credit: City of Mannheim.

The City Lab is located in Neckarstadt-West, an area that is often disadvantaged and known to be struggling with social problems but has a lot of creative potential. To tackle the challenge of the COVID-19 pandemic, a pop-up event was conducted in a public space in September 2020, asking passers-by to discuss existing ideas and contribute new views while respecting hygiene measures.

The SONNET project and the ideas arising from the City Lab were presented and discussed in numerous networks and meetings. The results were finally incorporated into a virtual interactive neighbourhood discussion in December 2020. More than 50 participants further developed the ideas for the local, social energy transition. In several small groups, lively discussions were held on the topics of environmentally friendly mobility, promotion, education and participation, and energy and housing.

To ensure citizen participation despite the ongoing pandemic conditions, the City Lab established the Mobile Green Room® in Neckarstadt-West from May to August 2021. This provided a stage for local organizations and associations to recruit supporters for their actions to implement the energy transition on a local level. In addition, there is an online participation portal where the ideas developed can be voted on, support can be offered and new perspectives can be brought in. The SONNET closing event took place in July, and ideas were integrated into the Climate Action Plan 2030 that is currently being developed.

The Mobile Green Room. Credit: City of Mannheim.

The KliMAthon – Gamification for Climate Action

The City of Mannheim and the Climate Action Agency together with the start-up Worldwatchers developed the KliMAthon, an app-based six-week CO2 challenge in which residents can playfully reduce their personal CO2 footprint. From 11 June to 24 July 2021, KliMAthon participants chose from more than 40 challenges from the seven areas of living, food, mobility, digital life, consumption, leisure and holidays. In addition, there are challenges that focus on everyday working life. The KliMAthon closed with a collaborative cleaning event in Neckarstadt-West with about 60 participants who collected waste throughout the neighbourhood. After the work was completed, the participants were rewarded with free ice cream at the Mobile Green Room®.

Local Green Deal Mannheim

The Local Green Deal is Mannheim’s answer as an urban society to the challenges in times of climate change and socio-ecological transformation. As a new approach for sustainable, climate-neutral and integrative urban development, it specifies the goals of the Mission Statement “Mannheim 2030”. It describes and designs the concrete local implementation along the eight thematic action areas for the European Green Deal. The Local Green Deal is not just another plan―it initiates, activates and bundles specific agreements for a green, clean and healthy city.

Networking to tackle the energy transition

Mannheim participates in the following climate-related networks:

  • ICLEI-Local Governments for Sustainability
  • Klimabündnis – Climate Alliance e.V.
  • Covenant of Mayors
  • Compact of Mayors
  • Global Covenant of Mayors for Climate & Energy
  • EUROCITIES

Thanks to the strong alliance with international and local partners, the business sector, and―most importantly―its own residents, Mannheim is well-positioned to master the energy transition.


About the authors:

Sabrina Hoffmann is working for the Climate Strategy Office of the City of Mannheim as sustainable city development manager. She pleads for sustainable urban spatial planning, green roofs and facades as well as the establishment of more climate-friendly mobility in Mannheim.

Viktoria Reith is working for the Climate Strategy Office of the City of Mannheim as climate adaptation manager. She is responsible for implementing the over 70 measures of the climate adaptation plan including water management, greening and health issues.


This blog article was co-created by Josephine Valeske and is part of the mPOWER blog series in which cities and towns share how they are building better energy futures.


Title Image Credit: Stadtmarketing Mannheim GmbH, Daniel Lukac