Andy Yan, Vancouver’s Duke of Data and Director of the Simon Fraser City program asks~what do we do when the glass towers that make Vancouver’s “Vancouverism” are sustainably outed as hungry power hogs? What is the 21st century sustainable version of Vancouver’s glass tower style? As reported in The Guardian and as Price Tags has previously written the iconic glass towers are becoming a faux pas “because they are too difficult and expensive to cool.”
As Simon Sturgis, an adviser to the government and the Greater London Authority, as well as chairman of the Royal Institute of British Architects sustainability group observed “If you’re using standard glass facades you need a lot of energy to cool them down, and using a lot of energy equates to a lot of carbon emissions.”
Because glass towers reflect a lot of heat into the buildings, air conditioning has been standard to cool towers. But the International Energy Agency now estimates that forty percent of all global carbon dioxide emissions come from construction, demolishing, heating and cooling buildings. And here’s a staggering statistic~the energy for air conditioning has doubled in the last twenty years, and makes up 14 percent of all energy used.
In New York City Mayor de Blasio is demanding that glass towers now meet new energy efficient standards, which really means less use of glass and steel in towers. While other cities have not yet grasped the connection between warmer hotter climatic conditions and glazed towers, new regulations will come under play to ensure that glass towers are efficient for the lifecycle of the building.
While glass does provide solar heat gain in colder weather, that is not too optimal in Vancouver’s overcast winters. Natural ventilation could ostensibly mitigate up to 70 percent of air conditioning loads, but locations in inner cities with traffic noise and air pollution may make that not a practical option.
There is glazing that can block out sunshine on hot days as used in The Edge building in Amsterdam. Using smaller windows on three sides of the building reduces heat gain, and the windows can be opened for ventilation. While the Edge is perceived as one of the most green buildings in the world, laminated glass panels used in these high efficiency buildings are expensive to fabricate, and pose a challenge for recycling.
What will the next reiteration of Vancouverism’s glass tower look like? And will that form be rethought as well?
Below is a YouTube video on The Edge in Amsterdam describing some of that building’s innovations.