Australia is at a key stage in its evolving energy landscape, with offshore wind turbines being explored as a potential contributor to electricity generation and emissions reduction efforts. As the energy sector shifts, offshore wind in Australia presents an option for large-scale power production that could support energy security and diversify the energy mix.
With nearly 34,000 kilometers of coastline and an estimated offshore wind potential of 4,963 gigawatts (GW), Australia has significant resources to develop this sector. This capacity exceeds the country’s current electricity demand, highlighting the scale of the opportunity for offshore wind integration.
Several regions are already progressing offshore wind turbine projects, reflecting growing momentum in this space. However, development requires careful planning to balance energy needs with environmental considerations. Factors such as marine biodiversity, noise pollution, and seabed disruption will need to be managed to ensure an approach that considers both energy production and ecological impacts.
The role of offshore wind turbines in Australia’s energy landscape
Victoria is at the forefront of Australia’s offshore wind energy development, with a target of 2 GW of offshore wind turbine capacity by 2032 – enough to supply power to 1.5 million homes. By 2040, this is projected to increase to 9 GW. Other regions, including Gippsland, Wollongong, and the Hunter-Central Coast, have been identified as potential offshore wind development zones, reflecting growing interest in this sector within the Asia-Pacific energy market.
Beyond electricity generation, offshore wind projects are expected to bring economic opportunities, including job creation and increased investment in coastal regions. They may also contribute to reducing dependence on fossil fuel imports.
From an environmental perspective, offshore wind energy is being explored as an alternative to coal and gas. The Australian Institute of Marine Science (AIMS) has reported that ocean warming and marine heatwaves, associated with greenhouse gas emissions, have had a significant impact on biodiversity. Since 2016, nearly 50% of the Great Barrier Reef’s coral cover has been lost, while Tasmanian waters have warmed at a rate four times faster than the global average, leading to a decline in giant kelp forests.
Offshore wind turbines and marine ecosystems
While offshore wind turbines can influence marine environments, research suggests they may also offer ecological benefits. One notable effect is the creation of artificial reef habitats, where turbine foundations provide surfaces for marine life to colonise. These submerged structures attract species typically found in rocky environments – such as mussels, anemones, sea urchins, crabs, and fish – along with their predators, contributing to increased biodiversity in these areas.
Dr. Claire Szostek, an ecosystem services specialist at Plymouth Marine Laboratory, notes that offshore wind turbine foundations function similarly to shipwrecks or natural rock formations, offering surfaces for species like barnacles, mussels, corals, and sponges to establish themselves. This, in turn, supports larger food webs by attracting predatory species. Studies have also shown that commercially valuable crustaceans, such as lobsters, use the rocks and boulders placed around turbine bases for shelter, which can have localised benefits for fisheries.
Beyond biodiversity, offshore wind farms may contribute to fish population recovery by reducing fishing pressures. In some cases, offshore wind developments lead to restrictions on commercial fishing activity, creating areas where fish stocks can replenish. A study in the North Sea found that fish populations within offshore wind farm zones exhibited higher reproductive success and lower mortality rates due to the absence of large-scale trawling.
Challenges and mitigation strategies for offshore wind turbines
The expansion of offshore wind energy presents both opportunities and challenges, particularly for marine ecosystems. One key concern is noise pollution, which can affect marine mammals and fish that rely on sound for communication, navigation, and foraging. Offshore wind turbine installations may also influence seabed dynamics, potentially impacting benthic habitats and migratory species. However, research indicates that many of these effects are temporary, with ecosystems adapting over time.
Noise pollution
The construction of offshore wind turbines, particularly pile driving for fixed-bottom turbine foundations, generates underwater noise that can temporarily affect marine mammals. Studies indicate that pile-driving noise can reach up to 220 decibels (dB) at the source, making it one of the more prominent human-made underwater sounds. This low-frequency noise can travel long distances and may cause temporary threshold shifts (TTS) in marine mammals, temporarily reducing their hearing sensitivity. Migratory species such as humpback, southern right, and blue whales – commonly found in Australian waters – can be particularly affected during peak migration periods.
To address these concerns, a range of noise mitigation strategies is used. Bubble curtains – rings of air bubbles surrounding pile-driving sites – help absorb and scatter sound waves, reducing noise transmission by more than 90%. Soft-start pile driving, where hammering intensity gradually increases, allows marine mammals to detect and move away from high-noise areas before peak levels are reached. Additionally, seasonal construction restrictions, such as limiting pile driving between September and November in Australia, help minimise disruptions during critical migration periods.
Once operational, offshore wind turbines generate significantly lower noise levels. Research has found that turbine noise typically ranges between 130 and 150 dB – comparable to background ocean noise or a passing cargo ship – and does not exceed thresholds that would significantly alter marine mammal behaviour.
While the effects of offshore wind infrastructure on marine mammals continue to be studied, broader environmental factors such as climate change, commercial shipping, and fishing remain the primary threats to whale populations. Ship strikes alone are estimated to cause around 20,000 whale fatalities annually. Offshore wind farms, often located in areas with restricted vessel traffic, may help lower the risk of ship collisions, potentially creating safer migration corridors.
Entanglement in fishing gear is another significant risk for marine mammals, particularly species like the North Atlantic right whale, which has experienced severe population declines due to interactions with lobster and crab pot lines. Unlike large-scale commercial fisheries, offshore wind farms do not introduce netting or trap systems. In some cases, offshore wind development has led to the establishment of no-fishing zones, which may reduce entanglement risks in specific areas.
Fish species, including cod and herring, have also been observed to alter their behaviour in response to construction noise, with temporary displacement occurring in some areas. However, research suggests that fish typically return to offshore wind farm zones within weeks to months after installation, with no evidence of long-term population declines.
Seabed and habitat disruptions
Offshore wind farms interact with marine habitats, particularly during construction, when seabed disturbances can temporarily alter sediment composition and affect benthic ecosystems. Species such as crustaceans, mollusks, and bottom-dwelling fish are sensitive to changes in sediment dynamics, which can influence feeding and breeding areas. However, these effects are often temporary, with seabed conditions stabilising as natural sediment transport processes resume after construction.
To manage these impacts, developers implement scour protection structures – large rocks or artificial reefs placed around turbine foundations – to prevent sediment erosion. These measures not only stabilise the seabed but also create additional habitats for marine species, including commercially valuable populations such as lobsters and mussels. Research from Europe suggests that these artificial habitats can enhance local biodiversity, supporting reef-associated species and potentially leading to local biodiversity gains.
Careful site selection and marine spatial planning help minimise habitat disruption while considering potential ecological benefits. Developers prioritise locations with lower ecological sensitivity and phase construction schedules to limit prolonged disturbances. Long-term ecological monitoring ensures that any unexpected changes in marine habitats can be addressed through adaptive management strategies, such as promoting the recolonisation of benthic habitats and managing sediment displacement.
Electromagnetic fields from subsea cables
Offshore wind farms use high-voltage subsea cables to transmit electricity from turbines to the grid, generating electromagnetic fields (EMFs) that can interact with marine species sensitive to electric and magnetic fields. Sharks, rays, and certain fish species use electroreception to navigate and locate prey, raising concerns about potential behavioral changes. Some migratory species, including sharks and rays, may adjust their routes in response to underwater structures and EMFs, though long-term studies from European offshore wind farms have not found evidence of population declines linked to habitat modification.
Research on the effects of EMFs has produced varied findings. Some studies suggest that species such as brown crabs exhibit behavioural changes, such as aggregating near cables, but no evidence links these interactions to population declines or long-term ecological harm. In the North Sea and UK waters, studies on skates, rays, and electroreceptive fish found no significant changes in migration patterns or feeding behaviours near offshore wind infrastructure.
To minimise potential risks, offshore wind developers use shielding technologies that contain and direct EMFs, reducing exposure to marine life. Additionally, cables are typically buried one to two metres beneath the seabed, further mitigating EMF emissions and minimising interference with sensitive species. These measures align with industry best practices, ensuring that offshore wind infrastructure operates with a limited ecological footprint.
Ongoing monitoring and further research remain important for understanding long-term interactions between marine species and subsea cables. However, existing evidence suggests that well-designed offshore wind projects can integrate into marine ecosystems with minimal disruption to electroreceptive species.
Vessel traffic and collision risk
The development and operation of offshore wind farms involve increased vessel activity for construction, maintenance, and environmental monitoring. This has raised considerations about potential collision risks for large marine mammals, particularly whales, which are vulnerable to vessel strikes. However, research suggests that vessel traffic associated with offshore wind farms is not a primary contributor to whale mortality, and established mitigation measures help reduce risks further.
According to the US National Oceanic and Atmospheric Administration (NOAA), over 90% of whale strandings are linked to vessel strikes and fishing gear entanglement, with the highest risks posed by large cargo ships and tankers traveling at high speeds along major shipping routes. In contrast, vessels used for offshore wind farms are typically smaller, operate at lower speeds, and remain within designated areas, reducing the likelihood of interactions with marine mammals.
To further mitigate potential impacts, offshore wind energy developers implement measures such as speed restrictions and adaptive vessel management. Limiting vessel speeds to 10 knots in high-whale-density areas is one of the most effective ways to lower collision risks. These restrictions have been successfully applied in offshore wind farms across Europe and North America, demonstrating their effectiveness in reducing disruptions to marine life.
Additionally, dynamic vessel management strategies allow for real-time route adjustments based on whale sightings, further decreasing the risk of interactions. Advances in marine monitoring technologies, including thermal imaging, passive acoustic monitoring, and real-time tracking, support early whale detection, enabling vessels to take precautionary measures such as slowing down or rerouting when necessary.
Long-term studies from offshore wind farms in the North Sea indicate that marine mammals can adjust their movement patterns in response to increased vessel presence without significant long-term disruption. These findings suggest that, with appropriate safeguards in place, offshore wind infrastructure can operate in a way that minimises risks to marine mammals while supporting offshore energy development.
The role of floating offshore wind turbines
Floating offshore wind turbines are expected to play an increasing role in Australia’s energy development, offering a solution to the depth limitations of traditional fixed-bottom turbines. Most offshore wind farms globally use fixed foundations, but these are generally limited to waters shallower than 60 metres. Given Australia’s deep coastal waters, fixed-bottom technology may not be suitable for many areas with strong wind resources and good grid connectivity. Floating offshore wind turbines, however, can be deployed in depths exceeding 1,000 metres, making them a viable option for offshore wind energy development in several proposed zones.
The Australian government has identified multiple regions where floating offshore wind turbines may be the most practical choice. The Hunter Coast zone in New South Wales, for example, spans depths of 140m to 1,000m, placing much of it beyond the reach of fixed-bottom foundations. Similarly, the Illawarra region has depths ranging from 55m to over 1,000m, while parts of the Southern Ocean off Victoria and South Australia feature water depths between 50m and nearly 200m. In these areas, floating wind technology enables offshore wind development where fixed-bottom turbines are not viable.
Beyond enabling development in deeper waters, floating offshore wind turbines can also help reduce competition for space in busy coastal zones. Nearshore offshore wind projects operate alongside industries such as commercial fishing, defence, shipping, and tourism, all of which require careful spatial planning. By moving further offshore, floating offshore wind farms may help alleviate potential spatial conflicts while also reducing their visual presence – a factor considered in the design of Australia’s offshore wind energy zones. The recent decision to shift the Illawarra offshore wind zone further out to 20km from the coast following community consultation reflects the importance of these discussions.
Environmental considerations also differentiate floating wind from its fixed-bottom counterpart. Traditional offshore wind turbines require pile-driven foundations, which generate underwater noise that can affect marine mammals such as whales and dolphins. They also interact with seabed habitats, with potential long-term implications for benthic ecosystems. Floating offshore wind turbines do not require pile-driven foundations, reducing these particular concerns. Instead, they are anchored using mooring lines, which still interact with the seafloor but generally have a different environmental footprint compared to large monopile or jacket foundations.
However, floating offshore wind energy presents its own environmental considerations. Anchor systems must be designed to minimise seabed disturbance, and research is ongoing to assess the impact of mooring line movement, including ‘chain slap,’ which can interact with marine habitats. Another area of focus is the potential for entanglement risks for marine life, particularly migratory species. These factors are being studied by developers and researchers, and as Australia’s first floating offshore wind projects progress, environmental monitoring and adaptive management will play a key role.
One of the largest floating offshore wind energy projects currently in development is the 2GW Novocastrian Offshore Wind Farm in the Hunter region, led by Equinor and Oceanex Energy. This project, which has been awarded a feasibility licence by the federal government, represents a major step forward for Australia’s floating offshore wind sector. If approved, it could create approximately 3,000 jobs during construction and 200-300 permanent positions while making use of the Hunter region’s existing heavy industry and port infrastructure. The Port of Newcastle, one of the world’s largest coal ports, has also indicated plans to support offshore wind energy, positioning the region as part of the shift towards offshore energy development.
As Australia’s offshore wind industry evolves, floating wind technology is expected to play a central role in expanding its potential. When combined with robust environmental safeguards, community engagement with local communities, and careful monitoring of ecological impacts, floating offshore wind turbines could contribute to Australia’s energy mix while managing interactions with marine ecosystems.