Recycling? Shorter Showers? No. We Must Think Bigger.

Smart cities can be utilized to rethink the way we live to combat climate change. Like… making ski slopes out of trash.

Image from Majorel

Most of us will be city-dwellers in the future. Three million people are moving to cities every week, and by 2050, 68% of the global population is projected to live in urban areas. 😟

But with so many people living in cities, how will this affect the environment?

Cities take up 2% of global landmass while emitting over 70% of global CO2 emissions. Scary, right?

The Solution: Smart Cities

A smart city is a sustainable city that uses the Internet of Things (read more on that here) to integrate sensor data from across the city with the citizens to streamline efficiency and create meaningful change. It’s the high-tech approach to creating an eco-friendly city.

Copenhagen Cleantech Cluster

This involves three connected infrastructures: the physical, digital, and communicative.

The physical infrastructure involves the sensors that might help detect which parking spaces are open or the responsive systems that can act upon sensor data such as a district cooling system that takes into account the weather and temperature data.

The digital infrastructure involves the ways in which these physical parts “talk” to each other (can happen over WiFi, Bluetooth, etc.) and process the data. In smart cities, there is a massive trove of data being collected every moment so there must be a way to make meaning out of it.

The communicative infrastructure involves making this system scalable through smooth information flow. Because there are so many parties involved in this process from citizens, private companies, government, and the technology itself, there needs to be a way to easily connect and share data. This can be in the form of standardized coding languages, a smart energy grid, or open-source technology.

Wait… but how is this supposed to make a city more sustainable?? Next, we will look at case studies in Copenhagen, Dubai, and Rio de Janeiro.

Copenhagen, Denmark

Ranked the #1 sustainable city in the world by Lux Review, Copenhagen strives to be the first carbon-neutral city by 2025 (this means they create more energy from renewables than from “dirty” sources such as coal, natural gas, or oil).

Already, they’ve experienced a 20% population growth in the last decade. Yet they have cut emissions by over 42% over that same time period. Clearly, they’re doing something right.

Their road to becoming a smart city has used a dual strategy: Firstly, they are the world’s testbed for smart and sustainable solutions. They house the Copenhagen Solutions Lab, which is a 2km strip of the city (not a traditional lab!) that serves as an incubator for smart city initiatives. Secondly, they have a “sharing is caring” ideology that motivates them to share new information with other cities around the world and vice versa. It’s a true testament to how much faster we can get stuff done with we work together (I know that sounds cheesy, but it’s true 😁).

Some of their most successful initiatives have focused on mobility, pollution, and energy.

Biking Culture

Copenhagen has 5x more bikes than cars, and 62% of its citizens use bikes for their daily mode of transportation. This is up from the 36% that did in 2012 when the City Council originally launched their 14-year plan to improve the quality, safety, and comfort of cycling. Today, the city has lanes wide enough for 2–3 bikes and some “supercykelstis,” which are cycle superhighways that enable cyclists to go at higher speeds without car traffic. Electric bikes and scooters have also given senior citizens an opportunity to join the revolution,

Los Angeles Times

The city has also made significant efforts to make car ownership expensive and challenging, such as charging more for parking tickets.

Air Pollution Control

Air pollution causes 7 million deaths annually. In Copenhagen, 550 people die annually (out of a population of 600,000). This city has dealt with this issue by partnering with Google to devise a method to track local air quality throughout the city using a Google Street View Car.

City planners, policymakers, and citizens alike can use this data to decide where to create infrastructure or find the least polluted route to go for a run.

Image from Geospatial World

Trash → Energy → SKI SLOPE!

Image from Tomorrow Mag

Copenhagen has adopted a smart trash can network that tracks the “fullness” of the public trash cans across the city to optimize pickup routes and reduce trash overflow. IoT is utilized here to create a much more efficient system.

This trash is then taken to a power plant that generates power for 60,000 homes. But you will never believe how awesome this power plant is. 🤯

This power plant doubles as an architectural masterpiece and a SKI SLOPE!

Usually, power plants are a nuisance to their surrounding community. But architect Bjarke Ingels reimagined this idea to create a place to have fun.

Because there aren’t any hills in Denmark, he created an artificial ski slope. It’s 400 meters long, has four varying levels of difficulty, and has a “magic carpet” to transport skiers back up the hill. There are also running trails and climbing walls along the sides as well.

Sustainable City, United Arab Emirates

A $354 million housing complex built sustainably from the ground up 18 miles outside central Dubai, this place is truly future-ready. From energy efficiency and water recycling systems to a communal farm, Sustainable City will help shape the future of smart cities.

Here, sustainability has been built into the way of life.

Image from National Geographic

Energy Savings

Look at the image above. Hmm, that’s weird… there are no cars?

That’s because most neighborhoods here are car-free. This means most people bike, use public transport (electric buses), or take horse-drawn buggies. When someone buys a house here, they either get a free electric golf cart or $10,000 off buying an electric vehicle. As a result, there are 250 charging stations to replace gas stations.

Image from Business Insider

The houses themselves are energy-efficient too. They are coated in reflective paint and equipped with thermal windows to reduce AC costs. Solar panels are installed on every roof, which has been incorporated with the architecture.

Image from ME Construction News

Resource Recycling

All greywater used by the community from showers or washing machines is taken to water treatment plants and fed back into the community. All black water (which contains unsafe human waste) is recycled into landscaping irrigation.

Of course, there are also trash recycling and composting programs that are easily accessible throughout the city.

Greenery and Farming

There are community gardens where residents can manage personal plots to plant food. Here, there are even beekeepers and chicken and duck-keepers and well.

In addition, there is a “buffer zone” around the perimeter of the city which acts as the first line of defense against pollutants. This consists of 2,500 trees scattered in multiple layers, purifying the air that comes into the city.

Image from Enerray

Fully stocked with fitness centers, equestrian centers, schools, malls, and more, this city is an example of what future cities could possibly look like. Although each complex goes for about $1 million, there are no maintenance and service fees. As these cities are built on a larger scale, they could hopefully become more accessible to the general population.

Rio de Janeiro, Brazil

Latin America’s first smart city, Rio utilizes an integrated command-and-control system to address the challenges they face regarding crime, transport, and natural disasters. They collect camera data from all over the city to monitor the city's activities constantly. This is used to collect traffic data to predict where accidents might occur and when flooding might hit in order to station an adequate number of emergency personnel.

Image from Urenio

Because they are located right above sea level, they are extremely vulnerable to flooding and landslides, particularly those who live in the slums because they are usually located on the sides of mountains.

To mitigate this issue, a project coordinated by UNICEF and a local organization called CEDAPS (Centro de Promocao da Saude) to digitally map areas in order to detect “danger points” such as rubbish heaps (which can become breeding grounds for mosquitos carrying dengue fever).

Image from UNICEF

But guess what! The people doing this work are local teenagers! By flying kites fitted with digital cameras, they take aerial shots of their neighborhoods. The data is then uploaded to a website and an online map.

Miguel Lago, one of the founders of Meu Rio, a tech platform that allows citizens to engage in issues that they care about, points out that these smart technologies need to work both ways. He says:

“These tools [IoT] can be used to control citizens but we need also to use them to allow citizens to control government.”

This is a reminder that smart cities need to listen to the voices of the people they are sharing the space with. As more and more smart cities are developed, this communication between citizens and government will become ever more important.

How will today’s biggest cities transition to becoming sustainable smart cities?

Each city has its own unique needs, which the “smart” version of that will have to account for. Depending on the climate, location, culture of people, and unique qualities, as seen in the three cities detailed above, the smart cities will look very different.

Cities that transition to becoming smart cities will need to be developed in phases, like Copenhagen or Rio, unlike places such as Sustainable City, where they can have more complex smart systems for water and energy right off the bat.

During this transition, there will be many technical, governance, and social challenges along the way.

Even though the individual technology necessary to implement smart cities is developed, the connection between a vast array of technologies to seamlessly create one smart system is where the challenge lies.

In terms of governance, the technology will need to be able to gather lots of data to work properly — in which case, there will need to be laws outlining the boundary to maintain people’s privacy.

Finally, a collaboration between cities that are transitioning to implement smart devices will be critical to rapid and successful development (like in Copenhagen). Nobody wins alone!


  • More and more people are moving to cities, and cities emit a lot of carbon. Smart cities are the key to making them more sustainable.
  • Smart cities utilize the Internet of Things to process sensor data from around the city to boost efficiency.
  • In Copenhagen, Denmark, they have a strong biking culture, air pollution monitoring systems, and they turn trash into ski slopes.
  • In Sustainable City, United Arab Emirates, they’ve created a “futureproof” community incorporating solar panels, recycling, and car-free living into the architecture.
  • In Rio de Janeiro, Brazil, they’re using smart camera systems to reduce traffic accidents and prevent flooding.
  • Collaboration between new smart cities and communication between citizens and government will be very important in the near future.

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Thanks for reading! Hope to see you soon 👋

17-yr-old innovator @theksociety 🙃

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