An initiative of Teknikföretagen, Viable Cities, UN-Habitat, Smart City Sweden, Vinnova, the Swedish Energy Agency, Expo 2020 Sweden and delivered by Nesta Challenges.


First stage: Open call to find city challenges, 9 November 2020 – 22 January 2021

Applications to the Climate Smart Cities Challenge Open Call have now closed.

If you have submitted an application please note that we will aim to inform all applicants of the shortlisted entries by early March 2021. If you have any questions during this time please see our FAQs or email 

To learn more about the open call to cities, please see below. 

News and Views about this Challenge

Helping cities achieve low-carbon futures


How to frame a city-based challenge


What a good city-based challenge looks like


Preparing to scale climate solutions in cities


More than half the world’s population lives in cities; cities are our global economic engines, centres of innovation and leaders in technology and policy development. The catastrophic risks of climate change coupled with rising inequalities, lack of affordable housing and transport options, and food and energy insecurity pose real threats to cities. Further, cities are major sources of greenhouse gas emissions.

The Climate Smart Cities Challenge is an opportunity for cities to participate as implementation partners in a city-based open innovation competition that will invite a global pool of technologists, businesses and investors to develop, test and scale cutting-edge solutions to reduce greenhouse gas emissions and create a better future for all.

We are looking for cities to partner with us to run a challenge, host a real-world testbed, and invite problem-solvers to compete to develop and scale potential solutions to their greenhouse gas challenges and create other social benefits.

These could include a wide range of interventions across multiple sectors or a combination, such as urban form and physical design, transport, waste management, food production, energy systems, housing, ecosystems, use of public space and others. Challenges that are carbon-negative are suitable as well (e.g. green space development).

We are interested in hearing about challenges that, if solved, would not only reduce or offset emissions but would also promote other sustainability and livability goals for your city.

For cities in the Global North, the opportunity is to create liveable and productive urban economies that deliver ambitious reductions in high per capita emissions footprints. For cities in the Global South, the opportunity is to deliver social and economic development for citizens in a way that is clean, green and avoids significant increases in emissions going forward. We want to partner with you wherever you are!

The Climate Smart Cities Challenge, including the three city-based challenges, will be launched at the World Expo in Dubai in October 2021. These three cities will be selected from the pool of open call applicants. 

About the Open Call

The first stage of the Climate Smart Cities Challenge is a global open call to cities. We want you to tell us about your city’s aspirations to reduce greenhouse gas emissions whilst creating thriving communities.


We are looking for cities to partner with us to run city-based open innovation competitions. These competitions will help the selected cities reduce greenhouse gas emissions and create other social benefits, by matching their needs with partners from across the world to develop and scale solutions suitable to their context. 

We want you to: 

  • Tell us about your city’s aspirations to reduce or eliminate greenhouse gas emissions and create a good future for all
  • Present a problem that is specific and solvable in the near-term, meaning potential solutions could be introduced, adapted and scaled within the next five years
  • Indicate a willingness to work with a global community of problem-solvers and investors and to commit resources to test and implement solutions to your problem in your city

This information will help us to design the Climate Smart Cities Challenge and select the partner cities who will help us run city-based challenges, planned to launch in 2021.

Please note: Applications to the Climate Smart Cities Challenge Open Call have now closed.

Watch the Climate Smart Cities Challenge webinar

What we are looking for (assessment criteria)

Applications will be assessed according to the following criteria which map to the questions in the application form. Scoring will be weighted and decisions made holistically to capture a diverse portfolio of cities and challenges in the shortlist.

The open call is seeking challenges that can form the basis of an open innovation competition, meaning cities and their partners should be open to a variety of different approaches to solving the problem, and be willing to work with new partners (e.g. SMEs, technologists, other solution-providers) to solve them. We strongly believe that the best solutions come from unexpected places so a capacity to work with a diverse range of stakeholders is critical.

A suitable challenge for an open innovation competition:

  • Has a clear goal that’s open to different organisations using different approaches
  • Would benefit from new people working on it (e.g. there is not enough innovation in the field, or there is expertise from other fields or contexts you want to bring in)
  • Would be able to attract new people to work on it (e.g. it would create business opportunities for them, or you are able to offer a route to procure the solutions)
  • Would support new work (not just fund existing or planned efforts)
  • Can create solutions that have a sustainable business model

For more about what makes a good challenge, see Nesta’s Challenge Prizes Practice Guide.

We want to know if solving this challenge will make a significant contribution towards reducing carbon dioxide and other greenhouse gas emissions – whilst promoting other social benefits. We’d like to hear about your ambition for solving the challenge, the kind of metrics you’d like to track and solutions you imagine coming forward. For example, consider the SDG 11 targets and indicators and initiatives that cut across sectors, such as Viable Cities’ four focus areas

We also want you to consider scaling, transferability and feasibility of potential solutions – is this a challenge that exists in other cities, and therefore could potential solutions be scaled and adopted elsewhere? Are solutions feasible in the near future? Is there application to cities in less developed countries?

We are seeking cities to partner with us to run a challenge and invite problem-solvers to compete, to test and demonstrate solutions, and bring the most successful ones to scale. 

We want to know if your city has a good understanding of the challenge and what it will take to solve it, and if your city can devote some time and resources to helping us run this challenge. This can mean political capital to support the challenge, human capital to help run it, financial capital to help fund it. We are interested in hearing how you envision collaborating with us, for instance which individuals or city departments we can expect to work with; and whether you propose to work with us as a consortium with local partners. 

Note that we are seeking a diverse portfolio of cities, including cities from both developing and less developed contexts. Our expectations will vary depending on the resources you have available.

Depending on the nature of your challenge and the anticipated solutions, a challenge in your city will likely require a real-world testbed: environments where innovation is tested in collaboration between users, innovators and, often, regulators and other institutions in the environment where the technology will be implemented. 

A testbed can be a physical place in the city but it doesn’t have to be – for instance it could instead involve access to datasets to experiment with, access to city assets or infrastructure, regulatory permission to test out an innovation, or an expedited route to public procurement. We are interested in hearing how you would approach testing innovation or hosting pilots or demos in your city. For more background, consider Nesta’s report, Testing Innovation in the Real World

Why cities should enter

If your city is selected as a partner, you will get:

  • The opportunity to co-design an open innovation competition based in your city around your specific problem, supported by a team of experts in innovation, challenge prizes, climate change, cities and sustainable development from UN-Habitat, Viable Cities and Nesta Challenges
  • A pool of solution-providers competing to solve your challenges


  • Access to potential investors and partners to implement projects in your city
  • Peer learning opportunities with other cities facing similar challenges
  • Profile-raising opportunity of being part of a global challenge, including being featured in the World Expo in 2021 and being profiled in a major media campaign over the course of the challenge

Timeline (click and drag items to the right to view more)

9 Nov

Open for entries

This begins the open call phase of the prize. The deadline for entries is 22 January 2021.

22 Jan 2021

Deadline to enter

Assessment and shortlisting will begin after this date.

March 2021

Cities shortlist

The cities will be shortlisted, selected and the challenge design phase will begin.

Oct 2021

Launch city challenges

This launch indicates the competition has begun and will continue until 2022.

Jan 2022

Announce city challenge solutions

Feb 2022-23

Testing, scaling and implementation of solutions

Eligibility criteria

Please note: Applications to the Climate Smart Cities Challenge Open Call have now closed.

If you have submitted an application we will aim to inform all applicants of the shortlisted entries by early March 2021. If you have any questions during this time please see our FAQs or email

  • Applicants can be a single entity or a partnership, but there must be one lead applicant organisation.
  • The lead applicant may be city/municipal government or equivalent, or a private-sector agency or a public-private partnership with responsibility for public services. If the city is not the lead application, the relevant city/municipal government or equivalent must be a partner on the application. 
  • A ‘city’ can be a settled place of any size population (there is no minimum population size), which may include a multi-city region or metropolitan area comprising more than one contiguous municipality or local authority or equivalent.
  • Your proposal must include a problem/challenge/barrier in reducing or eliminating greenhouse gas emissions in your city and creating other social benefits.

Please also note that the following organisations are not eligible to enter: Teknikföretagen, Viable Cities, UN-Habitat, Smart City Sweden, Vinnova, Swedish Energy Agency, Expo 2020 Sweden and Nesta Challenges. Any application linked to or involving these groups will be disqualified. Cities or organisations that are members of Teknikföretagen or Viable Cities are eligible to enter.

Further information about the Open Call:

The team

Kathy Nothstine

Head, Future Cities

Hannah Picton

Assistant Programme Manager

Olivier Usher

Head of Research