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A bold pathway to Paris: Decarbonise 1000 cities one city at a time.



The idea of decarbonising 1000 Cities comes out of a need to make Paris real. And when 1000 cities are decarbonised, we will have achieved what is required to prevent dangerous climate change.  Why cities? Cities have a profound impact on the global trajectory of emissions through the decisions that they make. Cities are the hub of economic activity, drive culture, influence land-use, determine transportation networks and talk to each other without the political complications encountered at the level of nations.  In order to support 1000 cities in decarbonising, a rigorous, integrated, step by step, city by city process is required that unites technical analysis, capacity building, community engagement, peer learning, financing and funding and implementation support. There are a whole host of exciting and innovative city-level programs that can be engaged in this effort, and indeed are already engaged in different pieces of this picture, but these pieces have not yet been put together in a comprehensive package.

SSG and whatIf Technologies have developed CityInSight, a sophisticated, city-scale energy, emissions and finance model. CityInSight is designed to evaluate the impact of land-use and planning decisions on a low or zero carbon future, as well as a wide range of technologies, policies and initiatives. CityInSight needs to be used by every major city in the world to guide its infrastructure investments and planning regimes to avoid locking in patterns of land-use that are reliant on high per capita fossil fuel use. CityInSight can help guide planners, policy makers and financiers in making decisions that enable the decarbonisation of cities. 

CityInSight is currently being used by the cities of Toronto (See TransformTO) and Markham and the Region of Waterloo 

The Ask

SSG is looking to develop and implement state of the art decarbonisation climate action plans for 1000 major cities in the world within the next 10 years. To do this we need partners- cities, analysts and organsiations that can finance the transition in cities. We need to mobilise trillions of dollars to finance this transition in cities- the good news is that most of these investments will generate a return and there are trillions of dollars looking for exactly this type of investment.

What actions do you propose?

Every city is different, in its stage of development, its rate of population development, its culture and the form of its built environment. A systematic and meaningful approach to reducing emissions which is led by a city government will also deliver a range of co-benefits, including new opportunities in employment, cost savings resulting from reduced energy use, increased resilience in the face of extreme weather, improved quality of life as people use more and more forms of active transportation. These benefits are most effectively achieved when the city is considered as a system in both space and time, rather than as its constituent parts- buildings, transportation and so on. Once a model of this system is created, it is possible to identify opportunities that are synergistic and that are appropriate to place. This modeling, however, to ensure its local applicability, must be undertaken in conjunction with an ongoing community engagement process, which helps to identify and prioritise the options that make sense. This process, in addition to ground-truthing the actions, also results in enthusiasm and commitment by citizens, staff and innovators.

There are numerous other initiatives related to cities and we are familiar with and involved in many. In the best case scenario, the 1000 cities effort would unite all of these partners in a project with a much higher level of ambition and financing, think the Marshall Plan for Cities.

Transforming the built environment in 1000 cities to achieve deep emissions reductions requires billions of dollars of investment. But how does a specific city identify the most effective strategies or actions in which to invest? We propose a combination of three inputs; firstly lessons from their peers (and organisations such as ICLEI and C40 provide considerable guidance on this aspect already); secondly from their citizens including City staff as these people live and work in the City and have considerable insights into its functioning; thirdly from a detailed modelling process that represents the current energy system and then citizens and staff can develop and explore the implications of different policies and strategies on future outcomes. We term the process that brings together these three inputs in a detailed step by step method, community energy planning.  The exact steps and method used varies according to each city, but these three ingredients are critical. Once a substantive community energy plan is developed, the pathway for investments becomes clear and cities can move forward with meaningful initiatives that will contribute to deep emissions reductions as well as providing a wide range of co-benefits.

This effort will draw on lessons from the Emerging and Sustainable Cities Initiative from the Inter-American Development Bank, the Compact of Mayors, the Covenant of Mayors and Rockefeller Foundation’s 100 Resilient Cities. But at its core, it will include:

1.     Commitment by Mayor and Council

2.     Development of a Climate Action Plan including:

·       Meaningful citizen engagement

·       Integrated energy, emissions and finance modelling

·       Development of deep emissions pathways and targets

·       Identification of specific strategies, policies and actions

·       Analysis of co-benefits

3.     Long-term financing

4.     Implementation

5.     Monitoring and evaluation

Bilateral and multilateral peer support mechanisms would be applied on an ongoing basis.

Details on CityInSight

CityInSight is a foundational tool in this effort as it allows cities to quantify the impact of different strategies in terms of energy and emissions as well as relating these strategies to urban planning and social and economic outcomes.

Considerable effort has been invested in the last 15 years or so in developing methods for assessing the GHG emissions associated with cities and until the COP in Lima, there were a number of different standards that were used. In Lima, WRI, C40, ICLEI, UN Habitat and the World Bank launched a common standard, the GHGProtocol for Cities (GPC for short). CityInSight uses the accounting framework of GPC to ensure consistency with the work of these entities. CityInSight's strength and unique qualities however are its ability to develop detailed future scenarios that are spatial. In other words, CityInSight keeps track of the location of stocks of buildings, equipment within those buildings, vehicles and so on to enable City staff and community members to develop scenarios that reflect different land-use strategies, retrofit approaches, district energy and so on. Because it is a systems dynamics model, it also captures feedback between the strategies. The other powerful element of CityInSight is that it contains a detailed financial analysis so that a preferred scenario including not only the implications for the energy system and emissions, but information to enable the City to begin preparing a detailed financing package.   

Approaches to identify and evaluate strategies

How is geography incorporated?

Geography is at the heart of the approach. This determines people’s access to transit and other services, how often they walk and cycle, the shape of dwellings, the feasibility of district energy and other variables. GIS informs detailed land-use accounting in the model.

How are energy and GHG projections completed?

Energy and GHG emissions are derived from a series of connected stock and flow models, evolving on the basis of current and future geographic and technology decisions/assumptions (e.g. EV penetration rates). The model accounts for physical flows (i.e. energy use, new vehicles by technology, vehicle kilometres travelled) as determined by stocks (buildings, vehicles, heating equipment, etc).

How are scenarios created?

A scenario is a comprehensive package of policies and actions across all sectors. The scenarios can include a full range of factors such as behavioural incentives (rebates, taxes, grants) and regulations (building standards, renewable energy portfolio standards, fuel source requirements). The model allows scenarios to be evaluated in terms of their impact on energy use, emissions and costs.

How is energy mapping undertaken?

Energy mapping has two dimensions- supply and demand. Supply combines a technical review of the energy resources with local knowledge to identify opportunities. Demand is generated based on household and non-residential energy consumption spatially distributed.

How are assumptions described?

Locally appropriate assumptions are identified where possible. All assumptions are transparent and reviewed by the client as part of a Data, Methods and Assumptions Manual prior to use in modeling.

How is transportation energy accounted for?

A GHG transportation model identifies trip producers (households) and trip attractors (non-residential buildings) and calculates the spatially explicit trip flows on the landscape for each scenario. A portion of trips are assigned to: walking and cycling for those households in close proximity to destinations; transit, for those with access to public transportation.

How are financial impacts assessed?

Energy cost curves are developed for each community and the energy consumption drives energy costs on a year over year basis. Like a leaky bucket analysis, energy expenditures are framed as an economic development opportunity. Investment and capital costs are amortised to reflect the cost of district energy or renewable energy technologies. Social cost of carbon is calculated to reflect the economic damage caused by climate change.

How are employment impacts assessed?

Employment estimates are generated on the basis of investments in new technologies, energy conservation or other policies and actions.


This prezi shows the major components of the CityInSight model and the first level of modeled relationships (influences) represented by the blue arrows. Additional relationships may be modeled during scenario development by modifying inputs and assumptions - specified directly by users, or in an automated fashion by code or scripts running “on top of” the base model structure. Feedback relationships are also possible, such as increasing the adoption rate of non-emitting vehicles in order to meet a particular GHG emissions constraint.

Further description of selected sub-models and relationships:

Population and demographics. City-wide population is modelled using the standard population cohort-survival method, disaggregated by single year of age and gender. It accounts for various components of change: births, deaths, immigration and emigration. The age structured population is important for analysis of demographic trends, generational differences and implications for shifting energy use patterns.

Residential buildings. Residential buildings are spatially located and classified using a detailed set of 30+ building archetypes capturing footprint, height and type (single, double, row, apt. high, apt. low), in addition to year of construction. This enables a “box” model of buildings and the estimation of surface area. Coupled with thermal envelope performance and degree-days the model calculates space conditioning energy demand independent of any particular space heating or cooling technology and fuel. Energy service demand then drives stock levels of key service technologies (heating systems, air conditioners, water heaters). These stocks are modelled with a stock-turnover approach capturing equipment age, retirements, and additions - exposing opportunities for efficiency gains and fuel switching, but also showing the rate limits to new technology adoption and the effects of lock in.  Residential building archetypes are also characterized by number of contained dwelling units, allowing the model to capture the energy effects of shared walls but also the urban form and transportation implications of population density.

Non-residential buildings. These are spatially located and classified by a detailed use/purpose-based set of 50+ archetypes, and the floorspace of these non-residential building archetypes can vary by location. Non-residential floorspace produces waste and demand for energy and water, and also provides an anchor point for locating employment of various types.

Spatial population and employment. City-wide population is made spatial by allocation to dwellings, using assumptions about persons-per-unit by dwelling type. Spatial employment is projected via two separate mechanisms: population-related services and employment, which is allocated to corresponding building floorspace (e.g. teachers to school floorspace); and floorspace-driven employment (e.g. retail employees per square metre).

Passenger Transportation. The model includes a spatially explicit passenger transportation sub-model that responds to changes in land use, transit infrastructure, vehicle technology, travel behavior change and other factors. Trips are divided into four types (home-work, home-school, home-other, and non-home-based), each produced and attracted by different combination of spatial drivers (population, employment, classrooms, non-residential floorspace). Trips are distributed - that is, trip volumes are specified for each zone of origin and zone of destination pair. For each origin-destination pair trips are shared over walk/bike (for trips within the walkable distance threshold), public transit (for trips whose origin and destination are serviced by transit) and automobile. Following the mode share step, along with a network distance matrix, a projection of total personal vehicles kilometres travelled (VKT) is produced. The energy use and emissions associated with personal vehicles is calculated by assigning VKT to a stock-turnover personal vehicle model. All internal and external passenger trips are accounted for and available for reporting according to various geographic conventions.

Waste. Households and non-residential buildings generate solid waste and wastewater, and the model traces various pathways to disposal, compost and sludge including those which capture energy from incineration and recovered gas. Emissions accounting is performed throughout the waste sub-model.  

Local energy production. Energy produced from primary sources (e.g. solar, wind) is modelled alongside energy converted from imported fuels (e.g. electricity generation, district energy, CHP). As with the transportation sub-model, the district energy supply model has an explicit spatial dimension and represents areas served by district energy networks.

Financial & employment impacts. Energy related financial flows and employment impacts - while not shown explicitly the diagram above, these are captured through an additional layer of model logic. Calculated financial flows include the capital, operating and maintenance cost of energy consuming stocks and energy producing stocks, including fuel costs. Employment related to the construction of new buildings, retrofit activities and and energy infrastructure is modelled.


Data collection

CityInSight can incorporate many diverse data sets for a city that are not typically integrated into a single model, but this requires a process of data collection. A data request will be issued to the City followed by a supported process to source appropriate data.

Data gaps

A key strength of this approach is that as more and more cities are analysed the accuracy of assumptions and proxies will increase, both expediting the process and filling in any data gaps.

Privacy issues

Privacy issues are frequently a limitation on the level of resolution of observed data from utilities. The bottom-up analysis of each dwelling and building type can be calibrated with the utility data to construct a building-type specific model.  This challenge also applies to industrial facilities which are vulnerable to privacy issues because of disproportionate energy use. We are able to model the emissions of these facilities, if observed data is not available publically from other sources such as the federal government.


We use sensitivity analysis to quantify uncertainty in the model’s outputs.

Health impacts

Health outcomes are influenced by a wide range of genetic and environmental variables and it can be exceptionally challenging to distinguish the contribution of the built environment to those outcomes. Our approach is to consider the influence of the built environment on  risk factors for health outcomes, recognising that there are evidence-based relationships described in the literature.

Discrepancy between modeled and observed results

We will calibrate variables for which there are two independent sources of data. For example, we will be able to calibrate the model against actual electricity data from the electricity distributor.


We provide a data, methods and assumptions manual to clearly and simply explain the rationale behind the model.

For a detailed overview of CityInSight, please see this webinar.



Who will take these actions?

A meaningful Climate Action Plan or City Energy Plan is led by the City Government but is supported by businesses, non-profits, foundations and citizens.  Financing is critical involving the public and private sectors working to develop new mechanisms for financing projects that often save money- for example, retrofitting an entire neighbourhood. Such an effort would likely need to be coordinated by an international entity with credibility, for example UN Development Program, with the support of UN Habitat, the development banks (most of which have specific programs for cities), ICLEI, C40, Compact of Mayors and others- in other words a broad tent. A program guide would be developed by the coordinating agency. Cities would apply to participate and would commit to developing and implementing a climate action plan over a specific timeline, as well as providing some funding for the planning stages to ensure their buy-in. A regional technical support team would then provide guidance and support to the City as it develops its plan, including in the use of CityInSight, as well as coordinating both bilateral and multilateral peer support in the form of, as examples exchanges, workshops and conferences. A regional financing team would evaluate the strategies, plans and actions identified in the climate action plan to provide or identify appropriate financing, using a combination of public and private finance 


Where will these actions be taken?

The action would start with a pilot city, anywhere in the world, and would scale up each year to involve more and more cities. The approach would be modified to address the social, cultural and economic context of each city.

How much will emissions be reduced or sequestered vs. business as usual levels?

If we assume that average population of a city is 1,000,000 people (there are somewhere around 500 cities with a population of greater than 1,000,000), than a 1,000 cities accounts for at least a billion people. Some estimates indicate that approximately 70% of global emissions are derived from urban areas and about 50% of the world lives in urban areas current.  Decarbonising 1000 cities would therefore directly reduce global emissions by approximately 20%. Since cities are major economic drivers, there would also be indirect impacts. In other words, the 1000 Cities Initiative could be a linchpin of global GHG mitigation efforts. 

What are other key benefits?

Reducing emissions results in a host of co-benefits. Specifically, reduced GHG emissions correlates with reduced air pollution, resulting in improved health and ecological outcomes.  A built environment that has lower GHG emissions is usually associated with increased walking and cycling, which also improves health outcomes. Considerable investment and work is required to support a city in eliminating fossil fuels and this can represent a major economic development strategy with a focus on new employment. 

What are the proposal’s costs?

This represents a major global effort with significant resource requirements to manage and operate a program. It also requires organisations with global reach. Based on our experience, the cost of a comprehensive climate action plan for one city as detailed above is approximately US$350,000 although this would vary from one city to the next. This fee would include data collection, analysis, community engagement and staff time.Additional technical support by the coordinating organisation would be approximately $200,000 US per city including data collection support, modeling support, coaching, peer support mechanisms and workshops.

Critical to this effort is providing financing, which requires from $1 to just under $8 billion according to one analysis. In this study these investments will generate savings of between 2% and 10% of the City's GDP per year- on other words they are good investments. 

Time line

This project would scale up over time, beginning with one city and then expanding to 10 cities and so. This model of expansion allows for learning while scaling up. 


Initial timeline

Fall, 2016- Climate Week- program is launched

Spring, 2017- First city is selected 

Fall, 2017- First climate action plan is completed and financing is placed

Fall, 2018- Ten climate action plans completed. Process is refined and reviewed


Related proposals


Human settlements, infrastructure and spatial planning. Chapter 12 of IPCC Fifth Assessment Report.

Cities and the New Climate Economy: The transformative role of global urban growth

Stockholm Environment Institute: Keeping Cities Green: Avoiding carbon lock-in due to urban development

Global Environmental Change: Exploring the economic case for climate action in cities