By 2050 there will be five billion urbanites, but, with pressure on resources and climate disruption, how will cities cope? New technology and conceptual design will be vital.
My daughter is an urban kid through and through. She was born in a hospital on a hill overlooking the city skyline. There is a library down the block, three parks within a 10-minute walk and dozens accessible by bus or light rail. She has weekly play dates with neighbours and makes regular appearances at the pool, science museum, and farmers’ market. The car is foreign and boring to her. She is one of three billion urbanites; by the time she is my age, she will be one of four to five billion urbanites.
These new centres of humankind represent the majority of the world’s GDP, resource consumption, and waste production. In the petri dish of earth, they are the dense clusters of life growing organically atop a global culture. But by the year 2050, these cities will have either reinvented themselves or burst at the seams.
If we play our cards right, the 2050 city will:
Recognise its context, situated within a natural and agricultural ecosystem that provides its denizens’ abundant raw materials, free crop pollination, and genetic diversity;
Be resilient, responding to long-term shifts through adaptive re-use and short-term shocks through high-tech smart devices and low-tech biomimetic designs;
Be inhabited by citizens who emit no more than one ton of greenhouse gases per person per year, due to their heavy reliance on efficient building design, decentralised generation, district energy systems, and multi-modal transit.
How do we get from here to there?
I won’t pretend that urban (re)design is straightforward. It requires conceptualising within the constraints of existing developments, tending to the often competing needs of various stakeholders, convincing the citizenry to vote with their pocketbooks for new financing, and accomplishing large-scale projects in a time frame that keeps the city and its resident industries competitive for talent and taxes.
All of these challenges will still exist when my daughter is an adult. What will be different, then, you ask? The one thing I can bet on with absolute certainty is that, before she knows how to drive, vote, or pay taxes, she’ll be able to simulate her city on the computer. Here’s an example:
As buildings typically account for the majority of end-use energy, she may first want to determine which of the city’s buildings are suitable for energy retrofits. She can capture information about the building with a camera, satellite images online, or a more new-fangled laser scan. From there, she can run an energy simulation online to tell her how the building could perform when optimised.
Perhaps the most simple of retrofits is a cool roof to reduce cooling loads during hot weather. To assess the city’s rooftops, she can analyse roof type, excluding complex or pitched roofs, or those already committed to other functions. She can also consider where rooftop photovoltaics (PV) make sense based on sun insolation values embedded in the software. To understand daylighting, the program tells her where the sun and its shadows will be at every hour of every day of the year. She might then connect to an economic calculator to determine whether PV panels make better economic sense than cool roofs for this district.
As most cities are contending with increasingly frequent and severe storms alongside already overburdened stormwater and wastewater systems, she’ll then use the tools to increase the relative amount of permeable versus impermeable surface, just as a hydrologist would, but without so much expertise required. By using conceptual design within the context of the existing environment, she’s more likely to consider low-impact development techniques. For example, she can look at the hydrologic effects of green stormwater infrastructure in an attempt to avoid the need for yet another costly wastewater treatment plant.
Data within the model then allows her to compare her conceptual sketch with reality for permeability vs impermeability, the effects of rain gardens, bioswales and green roofs, and the visual impact of one over the other. She can use industry calculators to estimate the financial benefits of green stormwater infrastructure in lieu of grey, which, according to the World Resources Institute, are sizeable.
Our customer, the City of Vancouver, has built a simulated version of their entire city by combining terrain files, building footprints, satellite photos and GIS data for parcels and streets into a 3D modelling program. With this, they can demonstrate how shifts in population affect density and how viewsheds would change due to new infrastructure projects.
We’re now working with the city to use hydrologic modelling to simulate sea-level rise and building information modelling to assess opportunities for mass building energy retrofit. These simulations are becoming even more affordable and accessible now that they run in the cloud, not the desktop. We will see how Vancouver’s stormwater system could be improved and its energy efficiency incentives for building owners better targeted, making the most of every municipal dollar and data point.
Philadelphia could adopt this approach to achieve its ambitious green stormwater infrastructure goals and NYC could do so for its new resiliency plan. Why are we using techniques from the 1800s like dams, levees, and clipboards when we have technology from the 21st century like 3D modelling, simulation, and cloud computing?
My daughter, your children, and their five billion future urbanite friends, would happily give this a try. I think we owe them this much.
This feature is written by Emma Stewart & originally appeared in The Guardian.