Aluminium industry accounts for 40% of 4.8Mt of global silicon consumption

In an exclusive conversation with Jan Coetzee, Vice President Commercial Americas at Ferroglobe and Bill Hightower, Vice President of US Corporate Affairs, on the vital synergy between silicon and aluminium industry. They both acknowledge that both silicon and aluminium have strategic importance for the energy transition, advanced manufacturing, and defence. They are complementary to each other. Not only silicon serves as a crucial alloying element in aluminium production, aluminium significantly drives silicon demand. About 40 per cent of silicon consumption worldwide is driven by the aluminium industry.

To know more such interesting facts, read the full interview.

AL Circle: Like aluminium, silicon is recognised as a critical mineral in both the US and Canada due to its strategic role in the energy transition and defence. Could you quantify the average aluminium and silicon content used across major applications such as solar, wind, EVs, grid infrastructure and defence systems in the US and Canada?

Bill Hightower: Like aluminium, silicon is recognised as a critical mineral not only in the United States and Canada, but also in the European Union, due to its strategic importance for the energy transition, advanced manufacturing, and defence. This is why the recent EU–US Memorandum of Understanding on a Strategic Partnership on Critical Minerals and the accompanying EU–US Critical Minerals Action Plan are so significant.

Silicon is ubiquitous in modern life. It is found in cell phones, automobiles, clothing, medical products, food applications and construction materials. Much like aluminium, if the supply of silicon were suddenly disrupted, large parts of the global economy would effectively come to a halt.

This broad and strategic exposure explains why the US government is acting decisively to secure domestic, or at least plurilateral, supply chains for critical materials such as silicon and aluminium, and to deter unfriendly nations from weaponising these supply chains.

Jan Coetzee: Global silicon metal consumption is estimated at approximately 4.8 million tonnes in 2025. Around 40 per cent of this volume is consumed by aluminium applications, another 40 per cent by chemical applications such as silicones, and most of the remainder by polysilicon production. Silicones alone are used in more than 5,000 end‑use applications, including healthcare, food processing, sealants and construction materials. Polysilicon is primarily consumed in photovoltaic solar panels and semiconductors.

Many of these applications are inherently strategic. Electric vehicles rely on silicon both indirectly through aluminium alloys used for lightweight structures and battery casings and directly through semiconductors and power electronics. Solar panels require silicon cells to convert sunlight into energy, while aluminium frames containing silicon provide structural support. Defence systems similarly depend on advanced alloys and electronics that are not possible without silicon.

In addition, new applications are emerging. Silicon is increasingly being explored as an alternative to graphite in battery anodes, where it can significantly improve charging time, capacity and overall battery life.

AL Circle: Silicon remains one of the most important alloying elements in aluminium used in the 10–12 per cent range for casting alloys to improve fluidity and performance. With North American aluminium demand expected to rise, how do you see silicon demand from the region’s aluminium sector evolving through 2032?

Jan Coetzee: A meaningful increase in domestic US silicon consumption is expected over the coming years, and plans have already been announced to expand capacity in the United States in anticipation of this growth.

This increase is driven by the need for a secure, US‑based supply chain for upstream inputs, resurgence in domestic manufacturing - particularly in solar, new battery technologies, and manufacturing innovations such as giga‑casting. These advanced casting technologies, used for large structural vehicle components, are highly silicon‑intensive.

It is important to distinguish between primary and secondary aluminium production. Globally, aluminium production totals around 100 million tonnes per year, with approximately 70 per cent primary aluminium and 30 per cent secondary. Primary aluminium, produced from bauxite, generally requires low silicon additions—typically between 0.2 per cent and 1.5 per cent, depending on the grade. Secondary aluminium, produced from recycled scrap and used mainly in castings, requires significantly higher silicon content, typically between 5 per cent and 15 per cent, and in some cases up to 20 per cent.

While secondary aluminium represents a smaller share of total production, it is therefore much more silicon‑intensive and significantly more energy‑efficient, consuming roughly 20 times less energy than primary aluminium production.

The United States has a well‑developed scrap recycling industry, and today secondary aluminium accounts for more than 80 per cent of domestic aluminium output. Primary aluminium production in the US has declined sharply and currently stands below 700,000 tonnes per year, or roughly 15 per cent of total output, largely due to higher energy costs. By contrast, Canada produces approximately 3.3 million tonnes of primary aluminium annually, supported by abundant hydroelectric power.

AL Circle: At present, how much silicon is consumed by the global aluminium industry in annual terms? Which aluminium applications remain structurally dependent on silicon, and are there any emerging uses that could materially lift future demand?

Jan Coetzee: Global silicon demand amounts to approximately 4.7 million tonnes per year, of which around 40 per cent is consumed by the aluminium industry. Silicon intensity varies by alloy grade, but many traditional aluminium applications—such as automotive, construction and household goods—are cyclical and track GDP growth.

As a result, demand growth in these segments is expected to remain modest, at around 1–2 per cent per year. In contrast, applications linked to the energy transition—including electric vehicles, solar power, semiconductors and advanced batteries—are growing significantly faster, at an estimated 8–10 per cent per year.

Future growth in silicon demand is therefore expected to come primarily from these technology‑driven applications rather than conventional aluminium alloys. Independent industry analysts project overall global silicon demand growth of around 5 per cent per year.

China currently accounts for approximately 80 per cent of global silicon production. As geopolitical considerations push North America and Europe to onshore strategic technologies, renewed investment in these regions is expected, creating opportunities for Western silicon producers.

AL Circle: 50 per cent of silicon consumed in the US is dependent on imports? How does this expose the country to significant supply chain disruptions? How do you see the growth opportunity of silicon production in the US over the next five years?

Bill Hightower: While approximately 60 per cent of silicon consumed in the United States is imported, domestic producers have the technical ability to activate additional capacity and displace imports when market conditions allow. The main constraint is not installed capacity, but market distortion.

The core challenge is China’s structural overproduction of silicon and the dumping of excess material into global markets, which depresses prices worldwide. These practices undermine domestic industries and ultimately create supply‑chain vulnerabilities. In the short term, low‑cost imports benefit consumers, but over time they erode domestic production capability.

In 2016, there were 16 silicon smelters operating in the United States. By 2026, that number has fallen to just three or four, largely due to dumping practices and significantly lower labour and environmental standards abroad. This mirrors similar dynamics in the aluminium industry.

There is now a strong policy and industrial push to rebuild these supply chains in the US. Growth can be achieved by reactivating idled capacity or investing in new, modern facilities aligned with real market demand. New investments are expected to focus on efficiency, quality and sustainability rather than volume‑driven overproduction.

In addition, the recently announced plan to develop a new 750 ktpa primary aluminium smelter in the United States by 2030 represents a significant opportunity to restore lost capacity and support growth across the broader aluminium and silicon value chains.

AL Circle: How much silicon does Ferroglobe currently supply to the global aluminium industry? Which markets are most commercially significant for you today, and where do you see the strongest growth opportunities emerging next?

Jan Coetzee: Ferroglobe typically ships approximately 35,000 to 45,000 tonnes of silicon per quarter globally, as disclosed in investor presentations, although volumes are not generally broken down by end‑use application.

As a leading Western producer, Ferroglobe supplies silicon across all major consuming industries. Looking ahead, growth efforts are focused on higher‑value applications, including polysilicon, batteries and other advanced technologies that require consistently high‑grade silicon.

AL Circle: Silicon production is highly exposed to electricity pricing, making it one of the more energy-sensitive industrial materials. How severely has the recent energy crisis impacted the industry’s margins, output and competitiveness? What structural solutions does the industry need beyond short-term mitigation?

Jan Coetzee: Energy is a critical cost input for silicon smelter operations. One of the most significant recent pressures on energy availability and pricing has been the rapid expansion of Data Centres, which are competing directly with manufacturing for power supply. Utilities are struggling to adapt quickly, while consumers remain resistant to higher electricity costs.

While Data Centres are essential for digital competitiveness, they generate far fewer long-term jobs than industrial operations, which can complicate energy allocation decisions at the community level. These pressures are expected to ease over time as new generation capacity and grid investments come online.

Energy pricing remains fundamental to competitive silicon production. Elevated energy costs have already put pressure on industry margins, and if they persist, producers may be forced to reduce output or increase prices. To manage this risk, producers must focus on right‑sizing capacity, improving efficiency and ensuring pricing reflects underlying energy costs. Long‑term competitiveness will depend on stable, affordable and increasingly low‑carbon energy supplies.

Biographies

Jan Coetzee, before being appointed at Ferroglobe, was responsible for the Ferrosilicon business in the EMEA region and the global market for manganese alloys. began his professional career in 1992 with ISCOR, then a large integrated mining and steel company that later evolved into several major entities, including ArcelorMittal South Africa, Kumba Iron Ore, and Exxaro Coal. In 2001, he joined Pechiney in South Africa following the acquisition of Silicon Smelters (Pty) Ltd. This business subsequently evolved through multiple acquisitions and shareholder changes into what is today Ferroglobe.

Bill Hightower is a seasoned leader who has filled senior-level roles with Fortune 100 manufacturing companies in the US, Europe and Asia. Throughout his career he has led government affairs efforts at the state and national levels. He has a record of creating strategic development value throughout the US and Europe, with an emphasis on technological breakthroughs, corporate partnerships, as well as working with government officials to strengthen the manufacturing sector.Bill began his career at Emerson where he created a $2 billion divisional strategic operational plan and investor relations elements for Wall Street. He also held senior executive roles at Eaton and Balfour-Beatty, where he led strategy and M&A initiatives in the US. In addition to his corporate experience, Bill served nearly a decade as a state senator.