Staff Reporter
18 October 2024 06:42
The renewable energy conversation often overlooks a crucial reality: the immense material and resource demands required to scale wind and solar technologies in a world already facing significant resource shortages and environmental challenges. To address these dual challenges, we must consider incorporating nuclear energy, argues Professor Michael Preuss.
Renewable energy sources like wind and solar are inherently low in energy density, meaning they require significantly more physical infrastructure to produce the same amount of electricity as fossil fuels or nuclear power. For example, a one-gigawatt (GW) wind farm needs hundreds of turbines, spread over vast areas of land, and demands large quantities of materials such as steel, copper, and rare earth elements. A nuclear plant of the same capacity requires about 10 per cent of the steel and concrete needed for a comparable wind farm.
This substantial material burden raises a pressing question: do we have enough resources to support a global energy transition driven primarily by renewables? As global energy demand continues to rise, so too will the need for infrastructure. A renewable-dominated energy future could strain the availability of key materials, posing a major challenge.
Material scarcity and rising demand
The global push toward renewable energy will dramatically increase the demand for materials like steel, aluminium, copper, and rare earth elements. These resources are critical for renewable energy systems but also for a wide range of other industries. For instance, the demand for copper—a key component in electrical systems—is expected to rise sharply, and supply chain constraints have already emerged in the renewable energy sector.
In addition to scarcity, the extraction and processing of these materials come with substantial environmental costs. Mining operations for copper and other materials often lead to deforestation, water pollution, and soil degradation. The sheer volume of materials needed for renewable energy systems could exacerbate these issues, putting ecosystems at risk and increasing the carbon footprint associated with energy infrastructure.
Nuclear power, in contrast, offers a far more resource-efficient alternative. With its lower material requirements per unit of energy produced, nuclear power places less strain on the global supply chain and reduces the environmental impact of material extraction.
Conflict minerals and supply chain risks
A less visible but equally important issue is the ethical and environmental implications of mining for materials used in renewable energy technologies. The production of wind turbines, solar photovoltaic modules, electric vehicles, and lithium-ion batteries involves the use of materials such as cobalt, lithium, and rare earth elements. These resources are not only finite but also associated with serious supply chain governance risks.
The extraction of these materials is energy-intensive and environmentally damaging, but it also has severe social implications. The mining of cobalt and lithium, essential for batteries, often takes place in regions with poor environmental protections and labour conditions. The term “conflict minerals” refers to tantalum, tin, tungsten, and gold—materials whose extraction is frequently linked to human rights abuses and the financing of violent conflicts, particularly in regions like the Democratic Republic of Congo. These ethical concerns must be accounted for in any conversation about a renewables-only energy future.
The carbon cost of construction
While renewable energy sources boast zero operational emissions, the carbon footprint of constructing the necessary infrastructure is often underappreciated. The production of steel, concrete, and aluminium—essential for building wind farms, solar arrays, and batteries—contributes to about 25 per cent of global CO2 emissions. Thus, the more renewable infrastructure we build, the more we contribute to these emissions.
The lifecycle emissions of renewables, from mining raw materials to transportation and assembly, create a more nuanced picture of their environmental impact. In contrast, nuclear power plants, with their smaller material footprint, generate fewer emissions during construction.
Energy storage and its material challenges
The intermittent nature of wind and solar power introduces another significant challenge: energy storage. Because wind and sunlight are not constant, large-scale storage solutions, such as lithium-ion batteries, are essential for balancing supply and demand. However, these batteries are resource-intensive, requiring vast amounts of lithium, cobalt, and other rare earth elements.
The extraction of these materials raises environmental and social concerns. Mining for lithium and cobalt can cause severe deforestation, soil erosion, and water contamination. Moreover, in some regions, the mining industry has been linked to child labour, poor working conditions, and environmental degradation. These problems are exacerbated by the finite availability of these materials, raising questions about the long-term sustainability of energy storage solutions reliant on them.
Nuclear: A necessary complement to renewables
At the heart of Australia’s discourse on nuclear energy is the binary fallacy of pitting renewables against nuclear. Beginning from the understanding that renewables are essential, many of our international peers recognise that a complementary technology is needed. The nuclear-renewables combination provides the low emissions of renewables with the reliable, continuous output of nuclear energy.
Australia’s nuclear opportunity
For Australia, this balanced approach could be crucial. Nuclear offers Australia the chance to not only meet domestic energy demands but also enhance its role in global decarbonisation through innovations like green steel production.
The global interest in using SMRs for producing “green steels” offers Australia another strategic advantage. With a strong raw materials export portfolio, Australia could pivot to producing high-value, low-emission metals and alloys, enhancing its role in the global clean energy market. In Italy, energy companies like EDF and Edison are already exploring SMR technology for decarbonising their steel industry. By integrating SMRs into industrial processes, Australia could similarly boost its economic competitiveness while aligning with global decarbonisation efforts.
These advanced reactors are projected to be commercially available by the early 2030s and could serve as a critical component of Australia’s energy mix. However, as demand for SMRs is expected to surge globally, without timely investment, Australia may be forced to the back of the queue and face SMR delays into the 2050s or 2060s.
Professor Michael Preuss, a senior lecturer at Monash University, specialises in nuclear materials and advanced manufacturing processes, with a focus on improving material performance in energy applications. His research includes collaboration with Rolls-Royce on advanced manufacturing technologies aimed at enhancing the durability and efficiency of materials in nuclear energy systems.