Interview with Sonia Dong

Position: Sustainability Engineer 

Organisation: AECOM 

One-liner: Sustainable design is the key to Sonia’s solutions.

The familiar mantra “reduce, reuse, recycle” is probably the best way to start and you can do it every day around the house. You can apply it not just to your household waste, but water and electricity as well.

The Interview

As a sustainability engineer, what are your biggest considerations when designing a new building in the city?

Grace, Moranbah SHS

Our biggest considerations as sustainability engineers are probably maximising energy efficiency, minimising material usage, and maximising user comfort. For energy efficiency, we model and provide advice on shading and insulation to minimise the heating and cooling energy required.

We also try to minimise the impact of the material we use in the building by identifying opportunities to use recycled materials, eliminating unnecessary material, and reducing the maintenance needed over the life of the building. For user comfort, we model and provide advice on thermal comfort, daylight, and indoor air quality, among other things.

At what age did you decide that what you do as a job now was something you wanted to specialise in?

Elsie, Western Cape College

I always enjoyed maths and problem-solving in high school, and I knew I wanted to do something that was positive for the environment. I was interested in learning a bit of everything, so I studied mechanical engineering, which is a jack-of-all-trades type of degree. Sustainability engineering is very broad and there as many things you can end up by specialising in. What I do now wasn’t really something I knew existed or could easily choose to study at the time.

I started my career in designing air conditioning systems for buildings, and stumbled into sustainability because the team needed a bit of extra help and I had spare time. The more I learnt about it, the more I realised it aligned with what I liked – a bit of everything – and I never left. In my short career, I’ve been able to apply my knowledge of maths, thermodynamics, fluid dynamics, materials science, programming, control systems, electrical systems, and more!

What’s your usual day or week like? Is it office-based or on-site?

STEM Girl Power

I spend most of my time in the office. I don’t spend too much time on site because my role is more about providing advice to other engineers who do the design – and they’re the ones who need to do the inspections. However, sometimes I go on site just to see them build what I’ve provided advice on, which is great fun.

Do you work with engineers and other specialists that you can bounce ideas off to come up with the designs?

STEM Girl Power

I get to work closely with everyone else on the project to think of ideas, help implement them, and model/assess the resulting benefits. Getting to talk to so many people and learning the detail about what they do is one of my favourite parts of the job. One minute I’m working with engineers and other specialists, then the next I’m working with project managers, construction teams, and even community engagement teams.

What is something everyone in the world could do to help protect the planet?

Grace, Kirwan SHS, Townsville

The familiar mantra “reduce, reuse, recycle” is probably the best way to start and you can do it every day around the house. You can apply it not just to your household waste, but water and electricity as well – reuse containers and bags, keep a bucket to collect water in the shower, and turn off the switches to appliances and lights you aren’t using. All of these little things add up to help reduce your footprint, and can also save you money in your bills – a win-win!

What sustainability initiatives in the M1 Pacific Motorway upgrade made a difference and can be used elsewhere?

STEM Girl Power

Pavements are usually responsible for the biggest material impacts on a road project. One of the main initiatives on the M1 Pacific Motorway was the use of a pavement construction technique called “crack and seat”, where instead of removing and reconstructing the existing pavement, you break it up into pieces, and use it as a base layer for your new pavement which is overlaid on top. This reduced the amount of waste, new material, energy and water that would normally have been required. This was the first project in Australia to trial and implement this technique – and we hope it can be rolled out across other projects in future.

What were the benefits of your university exchange to Toronto?

STEM Girl Power

I got to do a lot of travelling and made new friends from all around the world, many of whom I still keep in touch with. This opened my eyes to many new perspectives, explore different landscapes, and I generally became more confident and independent in trying things that were unfamiliar or outside of my comfort zone. Several of the best experiences I’ve had since then are just by saying yes to things I would have been too scared to try before.

How did you find out about the position that you are in?

Grace, Moranbah SHS

I didn’t even know the position existed until I started my job working in another team designing air conditioning and ventilation. One day the sustainability team showed our team where they had to model the airflow in an auditorium to improve ventilation in the higher seats, where people were becoming light-headed and fainting. I thought that was an awesome application of what I’d learned in uni. It was a great example of real-world problem solving, so I knew I wanted to do more of that! I think the demand for sustainability consultants has increased significantly in the last few years, so those types of positions are advertised more than they used to be. There are also more options available to study for them too.

How do you think sustainable design can become mainstream and retro-fitted into existing houses so everyone can contribute, not just in new buildings?

STEM Girl Power

The mantra I mentioned earlier of “reduce, reuse, recycle” is a good place to start. For renovations, you can look at improving shading and insulation – that can improve the comfort in your home and reduce the amount of air-conditioning needed. Within a house, considering what materials you use can also help – not just to reduce your material impact, but again choosing the right materials can make a difference in how cool or warm your house is. Using second-hand furniture and separating out recycled and organic waste are some other things you can do in an existing home even if you have limited other options. The more people to adopt these strategies, the more mainstream they’ll become until, hopefully, it becomes normal for everyone.


Sonia Dong is a Sustainability Engineer currently working for AECOM where she combines her technical engineering skills to projects with a passion for sustainable design.   

A large part of her job is helping deliver sustainability ratings for buildings and highways projects. One of her project highlights has been undertaking modelling for 80 Ann St – a commercial office tower in Brisbane – to identify the optimal combination of control system requirements, indoor and outdoor weather conditions, and façade design to maximise natural ventilation opportunities while maintaining user thermal comfort in Brisbane’s famously hot and humid climate.  

She has also recently undertaken a sustainability assessment for a part of the M1 Pacific Motorway upgrade. This included modelling to determine the reduction in embodied carbon and other lifecycle impacts associated with various sustainability initiatives in the design.  

Sonia graduated from The University of Queensland with a Bachelor’s Degree (Honours) in Mechanical Engineering. As part of her university studies, she completed an exchange at the University of Toronto in Mechanical Engineering and Engineering Science (Aerospace) and worked as a research assistant and engineering faculty tutor to support other students.   

This year, Sonia joined Queensland’s National Science Week Committee to help engage the community in science and sustainability activities.  

Q&A with STEM Experts

Interview with Brett Leavy

August 25, 2021
Q&A with STEM Experts

Interview with Gail MacCallum 

August 25, 2021
Q&A with STEM Experts

Interview with Dr Andrew O’Neill

August 25, 2021