As urbanisation increases, how are engineers helping to ensure cities develop in a way that is sustainable, both for the communities that inhabit them and for the environment?
It is predicted that by 2030, more than 60 per cent of the world’s population will live in cities. This will grow to 70 per cent by 2050.
And, while cities occupy just three per cent of the Earth’s land, they account for 60 to 80 per cent of energy consumption, and 75 per cent of carbon emissions.
To mark World Engineering Day for Sustainable Development (4 March), we asked change-makers how engineering is shaping our lives.
With these figures in mind, experts are working to lessen the environmental impacts of our urban centres, including in the City of Adelaide.
Here are three ways city planners, engineers and others are attempting to make South Australia’s capital city more sustainable.
Unfortunately for Adelaide, the new planning rules are more likely to turn the city into something more akin to Beirut. A treeless vista of houses with 6m wide frontages
Urban density is being encouraged in a manner that fails to take into account the reactive soils that most of the housing is founded on. The Footings Group of EA South Australia have made submissions through EA that the movement in founding soils tree planting adjacent buildings envisaged is beyond the capacity of conventional house footings designed in accordance with the footings code AS2870 to resist.
House buyers will be unaware they are exposing themselves to risks of cracking and other adverse outcomes due to unquantifiable foundation soil movements. The knowledge and the mitigating designs that have been developed since 1980 are now being set aside with an adventre into a brave new world. We are currently grappling with the prospect of being uninsurable if we practice in the area of urban footing design.
The advertising about cities being powered by renewable energy from wind and solar , both DC generation, is misleading as it tells only half the story. Cities are not powered by wind and solar at night and when the sun has died after 4 pm and wind does not blow. Powering is an instantaneous concept of force, not energy-what you should be stating is the ENERGY from renewables when available is used to supply cities. When it is not available say at night, energy is imported from other more reliable synchronous generation, coal, gas, nuclear, hydro. Renewables do not give reliability, availability and inertia to an AC electricity system–only synchronous machines able to run 24 hrs a day provide the availability modern society wants, 99.99% of the year, at the flick of a switch. You cannot run a city on an AC system entirely from all DC sources–FULL STOP. There is an engineering design limit on how much renewables are operationally possible.Renewables only partially supply energy less than 1/3 of the day.
It is important that more people are concerned with finding ways to improve the situation on the planet. Being aware of the great carbon emissions and the great energy consumption of our cities, actions are needed as soon as possible, in order to work to reduce the terrible environmental impacts that this entails. Conveying this information is vital, and infographics are a very creative way to do it and one that I really like. – Gustavo Copelmayer, Development Director.