“Globally, buildings account for more than 33% of total energy consumption. But the construction sector receives less attention and action when it comes to sustainability,” according to Mohamed Lachemi, professor at Toronto Metropolitan University.
To change this reality, scientists from all over the world recently shared their research and findings during the 10th World Sustainability Forum (WSF) that took place on September 14th in Singapore, Basel and Toronto. I went to the Toronto Hub – which was focused on green, low carbon and smart cities – and here are some of the key breakthroughs researchers shared at the event.
Sustainable concepts for concrete
Take for example concrete, which is made by aggregates of sand and rocky materials: it is the most used material in construction and is also known to be a very unsustainable material. Not only are its components mined, but also – when used in buildings – significant amounts of thermal energy are lost through the building’s envelope.
Professor Lachemi, one of the speakers at the event, studies concrete and improving its properties is crucial especially for growing cities such as Toronto. At WSF he shared how he integrated MPCMs – which are materials that can absorb and release thermal energy – into engineered cementitious composites (aka concrete) to optimize its thermal capacity.
His findings showed promising results. By integrating MPCMs to concrete, energy can be saved and when used in buildings’ envelopes, it can also reduce maintenance operations, thanks to the self-healing properties of the material. The cost of this new type of concrete though is higher than the actual cost of conventional concrete. “It’s hard to say how much more because it depends on the various materials used and where it is made,” explains Lachemi.
According to the professor, the price could be lowered by using the material in buildings’ envelopes only and not necessarily elsewhere. “It’s definitely a niche product and further research is needed to minimize the cost of material. I encourage people who work in the field to find local materials especially waste products like we did in our experiments,” he adds.
Digital tools for decarbonization
Another way to build sustainable cities was shared by Professor Ursula Eicker and founder of Next-Generation Cities Institute at Concordia University. She has created digital tools to help cities find the best decarbonization strategy for them. For example, the tool “Citylayers” combines and updates all data about buildings, trees, etc. in cities. “The novelty of this tool is to provide access to modelling tools. It’s not pure visualization,” she explained.
The idea is to create a digital twin of a city that allows the creation of user-centred decarbonisation strategies by simulating scenarios. Users can, thus, lower existing buildings or add floors, try different models of healing and cooling or even change electricity demand and calculate costs and savings. By mapping cities, Eicker and her team wanted to provide a tool that could be used in real life and share data to enrich and validate urban models.
“But the data is not easily found nor accessible in some cases,” she laments. While creating their digital tools, the professor and her team had “a lot of data but the quality was not good and it was harder to get information on mix-uses building.” For her, the biggest challenge is the lack of transparency because she can only start modelling neighbourhoods once all the data is clear which makes the process longer.
According to Eicker, every entity in cities should disclose information about their emissions. For example, New York passed a law in 2022 that asks exactly that for every building. On top of that, cities should reduce their consumption with the help of regulation and tools like the one she has created at her institute to make sure that the decarbonisation strategies used are the best. Although she is not currently a specialist on mobility, she is now working on that aspect as well: to add transportation into the already existing digital tools.
Many amazing ideas were presented at the 10th World Sustainability Forum and the event showed that scientists are working hard and finding creative answers to face climate change. I also saw that, in the scientific community, people help and support each other: a glimpse – hopefully – at communities in our future sustainable cities.
Andreia Portinha Saraiva is a freelance journalist from Switzerland currently spending time in Canada. EJ’s NextGen Perspectives column helps provide an inclusive look at the various youth voices involved in the environment industry.
Featured image credit: WSF