Ensuring Australia’s Water and Energy Security

In my industry, the secure supply of water and power remain critical focuses, particularly in the face of ongoing climate change and the push for sustainability across industries and nations.

Here in Queensland, a critical component for ensuring water and power security is through the various dams we have across the state. However, as many of these structures were built some 70-80 years ago, there’s significant need to update and modernise infrastructure.

Following an independent review, Seqwater found that improvements were needed at 26 regulated dams to bring them in line with dam safety and engineering standards. This need led to the development of Seqwater’s Dam Improvement Program, which aimed to improve the ability of dams across Southeast Queensland to withstand flooding, earthquakes, and other extreme weather events.

Running corollary to Seqwater’s program is Sunwater’s Dam Improvement Program, which includes upgrades to improve the longevity, safety, and resilience of Sunwater’s 19 referable dams. Under this program, there will be upgrades to Burdekin Falls Dam, Paradise Dam, Teemburra Dam, Leslie Dam, and Coolmunda Dam.

Sunwater’s program has already resulted in the completion of works at Fred Haigh Dam in 2007, Bjelke Peterson Dam in 2008, Tinaroo Falls Dam in 2011, Kinchant Dam in 2014, Eungella Dam in 2016, the strengthening concrete spillway base at Paradise Dam in 2017, the laying of foundation drainage at Burdekin Falls Dam in 2017, and a $170 million upgrade at Fairbairn Dam in 2020.

Leveraging the Power of Desalination

While upgrading dam infrastructure is important, another valuable resource in ensuring water security is through desalination. There are about 15,000 desalination plants around the world. Saudi Arabia has some of the largest desalination facilities in the world, such as the Shoaiba and Al Jubail complexes, which can each produce over 800 million litres per day.

In Australia, there are about 270 desalination plants across the country, most of which are small-scale plants that desalinate seawater or brackish water. However, there’s a growing need to understand and explore desalination further as Australia is projected to see up to 10% less rainfall across the south of the country by 2030, and 20% less by 2050.

Following the Millennium Drought, which was our nation’s worst drought in living memory, six major desalination plants were constructed across the country with the largest in Victoria as it was the state hit hardest by the dry conditions.

Desalination operates through two primary methods – distillation, which is a naturally occurring process done through evaporation or simple methods like boiling salty water and condensing the steam. Membrane processes, also known as reverse osmosis, is currently the more widely used method. It relies on a semi- permeable membrane with microscopic pores that separate bacteria, viruses, salt, and other impurities leaving only fresh water. Most desalination plants built recently in Australia use this method.

Around 40% of the water that goes through a desalination plant comes out as fresh drinking water. The remainder, known as brine, is pumped back into the ocean and poses potential environmental concerns as the salts and minerals extracted from the seawater forms a hyper saline slurry with a significantly higher salt concentration than seawater. The high density and salinity of this brine waste can accumulate in and around disposal areas, smothering bottom dwelling species and altering coastal ecosystems.

While diffusers are used to mix brine with seawater and disperse it at several different discharge points from desalination facilities, the large-scale uptake of desalination could overtake these protective measures. Currently, there is an absence of detailed scientific studies on the impact desalination plants may have on marine ecosystems.

Desalination Plants Across Australia

The Australian Government invested $20 million in funding to the National Centre of Excellence in Desalination Australia in 2009 to conduct research supporting the development and commercialisation of innovative technologies in desalination. Major coastal cities in Australia have invested in desalination plants to improve water security.

In Western Australia, ongoing rainfall shortages have had a significant impact on dam flows, making desalination plants a base load provider of water. Perth Seawater Desalination Plant produces 45 billion litres of fresh drinking water annually, which is around 17% of Perth’s water supply. The Southern Seawater Desalination Plant in Binningup produces 100 billion litres of drinking water per year. In 2020-21, water produced by the Perth and Southern Seawater Desalination Plants made up 47% of the city’s water supply.

In New South Wales, Kurnell Desalination Plant is currently the largest plant in the country, with the capacity to supply about 250 million litres of drinking water per day, supplying 15% of Sydney’s water needs.

In Victoria, Wonthaggi Desalination Plant can produce 150 billion litres of water per annum with the capability to expand to 200 billion litres a year. Queensland’s Gold Coast Desalination can produce up to 45 billion litres per year of drinking water for the Gold Coast, Logan, and Brisbane. And in South Australia, Adelaide Desalination Plant can produce up to 100 billion litres of water annually.

New desalination plants are in various stages of construction across Australia. For example, in South Australia, Kangaroo Island’s new desalination plant is expected to improve drinking water security and support the island’s tourism and agricultural industries. The plant also aims to add a layer of bushfire resilience by reducing the region’s reliance on water network reconfiguration or carting water from the mainland.

Planning has also been approved for a new desalination plant in Belmont, New South Wales, to provide an enduring supply of water for the Lower Hunter Region. The new plant is expected to produce up to 30 million litres a day of drinking water, in response to droughts that have impacted the Hunter region in recent years.

Sustainable Energy Generation and Storage

As most forms of desalination are energy intensive and have the potential to increase greenhouse gas emissions, many Australian plants attempt to offset emissions by using wind power or purchasing renewable energy certificates.

Another important way to reduce environmental impact while ensuring energy supply is through pumped hydro plants. For example, Queensland will need at least 6,000 megawatts of long duration energy storage, which is why clean energy storage, including pumped hydro and large-scale batteries, will be crucial to secure Queensland’s long-term energy needs.

Pumped hydro is a tried and tested technology, accounting for about 97% of energy storage globally. It can store a large amount of energy for long periods, making it the perfect backup for other renewable energy sources like solar and wind as it provides long duration storage at a lower cost.

The Borumba Project will be the first long duration pumped hydro to be built in Queensland. The Department of Energy and Climate are also undertaking detailed analytical studies to assess the Pioneer-Burdekin project’s feasibility for pumped hydro development. Together, the two projects could have a combined generation capacity of up to 7 gigawatts.

While these projects and the massive investment supporting these works are important steps in ensuring the state’s energy security for years to come, there are significant lessons that can be drawn globally in terms of leveraging additive manufacturing to reduce costs, wastes, lead times and environmental impact throughout the construction lifecycle.

Global 3D Printing Case Studies

Additive manufacturing, also known as 3D printing, is becoming a commonly used practice in construction. For example, in 2021, a 12-metre 3D-printed pedestrian bridge was opened in Amsterdam six years after the project was launched. Named MX3D Bridge, the structure used 4,500kgs of stainless steel that was 3D-printed by robots in a factory over a period of six months before being craned into position.

The team behind the bridge claimed the technique showed how 3D-printing technology can lead to more efficient structures that use less materials. This robotic technology finally allows larger optimised designs to be 3D-printed in metal, which causes significant weight reduction and reduced impact for parts manufactured.

The Alan Turing Institute and Arup fitted MX3D Bridge with a network of sensors that allows the bridge to collect data and build a digital twin to keep track of its performance and health. The digital twin monitors corrosion, load changes, environmental conditions, and pedestrian use in efforts to further data-centric design.

Other construction projects that have leveraged 3D printing technology include, two bridges developed by the School of Architecture and Urbanism of the University of Shanghai, which were created from plastic and measured 4 and 11 meters respectively.

China is one of the first countries to embark on building bridges using additive manufacturing. An impressive 176 units of cement support the longest 3D-printed concrete bridge in China, allowing pedestrians to cross the Shanghai Canal. Two robotic arms used for the construction created its concrete arch in 450 hours and the team claims to have saved two-thirds of its implementation costs compared to conventional manufacturing processes.

Ensuring Sustainability Through Local Solutions

The growing use of additive manufacturing and plastics within road and bridge construction could be extended into waterpipes and other key elements that drive water security and sustainability. After all, the plastic material used in manufacturing waterpipes is engineered to be robust, reliable, recyclable, and designed to last a long time.

Plastic pipes are also lighter compared to other pipe materials, which increases the number of pipes that can be transported per truckload. Lighter pipes are also easier to install. For open trench installation, plant equipment is minimised compared to heavier pipe materials, which can increase lay rates and reduce carbon emissions.

Meanwhile, sustainability in infrastructure is also growing more stringent as all projects over $100 million must be rated by the Infrastructure Sustainability Council, which evaluates the economic, social, and environmental performance across the planning, design, construction, and operational phases of infrastructure assets. The IS Rating Scheme ensures sustainable outcomes as early as possible in the infrastructure lifecycle – driving the industry towards a circular economy.

Some critical challenges that the industry face are the ongoing lack of capacity, capability, and specialised skills for implementing more sustainable practices. While AI and 3D printing represent significant progress in streamlining construction and boosting efficiencies; there are few local manufacturers with the technology and workforce to implement such practices at scale. This is forcing various elements of the construction lifecycle offshore, negating the sustainability of production while increasing transportation costs and impact.

As Australia aims to become more carbon neutral, it will require significant investment in the technologies and skill development that can drive this reduction and transform the construction sector for the better. There’s much we can learn from overseas pioneers in this space – the real challenge is developing the same expertise and technology solutions in-house.