The four cities have been chosen!

We have announced the cities who have been invited to the next stage of the Challenge


Climate Smart Cities Challenge open call

An open call to find cities to partner with to develop solutions to greenhouse gas challenges

Nesta Challenges worked with Teknikföretagen, Viable Cities, UN-Habitat, Smart City Sweden, Vinnova, the Swedish Energy Agency and Expo 2020 Sweden to deliver the Climate Smart Cities Challenge open call. This was the first stage of the Climate Smart Cities Challenge and an opportunity for cities to apply to be  a partner to run an 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.

Why did we do this?

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.

What happened?

We were looking for cities to tell us about their aspirations to reduce greenhouse gas emissions whilst creating thriving communities.  .These could have included 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. 

We were 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 cities.

The full Climate Smart Cities Challenge will launch at the World Expo in Dubai in October 2021. 

About the open call

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

 We were 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 wanted to hear about: 

  • Your city’s aspirations to reduce or eliminate greenhouse gas emissions and create a good future for all
  • 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
  • Your 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

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

Criterion 1: Suitable for open innovation competition

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 Challenges’ Prizes Practice Guide.

Criterion 2: Potential for impact, scale and innovation

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?

Criterion 3: Your capacity to partner

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

  • 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.

News and Views about this Challenge

Four cities selected for the Climate Smart Cities 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


How can Swedish innovation promote climate-neutral cities?


Webinar: What to consider when defining your city challenge


Call to create healthy, thriving, climate-neutral cities


The team

Kathy Nothstine

Head, Future Cities

Hannah Picton

Assistant Programme Manager

Olivier Usher

Head of Research

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

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