Conductive materials are the backbone of our modern way of life. From AI and digitalization to electrification and the energy transition, none of today’s major technological revolutions would be possible without them.
At the same time, engineering priorities are shifting. As products demand lighter, more flexible, and higher-performance materials, engineers and designers are reassessing the materials they rely on. Increasingly, the questions they ask are:
- Does the material deliver sufficient conductivity for the application? Not every use case requires maximum current-carrying capacity.
- What secondary properties matter? Density, strength, flexibility, corrosion resistance, and thermal behavior often matter nearly as much as conductivity.
- Can it be produced at scale, affordably, efficiently, and abundantly? Cost and manufacturability determine whether a material remains niche—or becomes ubiquitous. Materials production is notoriously energy-intensive. The next-generation of conductive materials production should not put further strain on energy supply.
In this post, we explore the real-world strengths and limitations of today’s most common conductive materials—and then examine how Galvorn®, a next-generation advanced carbon material, offers a lightweight, high-performance alternative that challenges long-held assumptions about what conductive materials can be.
Please note: Properties are taken from Ashby’s Materials and the Environment unless otherwise noted.
Copper
Conductivity
Density
Moderate thermal expansion
Energy intensity
Annual production: ~26.5 Mt (≈70% for electrical uses)
Resistivity: 7 µohm∙cm
Thermal Conductivity: ~385 W/m·K
Thermal Expansion: 19 10-6/°C
Strength: 380 MPa
Density: 8300 kg/m³
Embodied Energy: 59 MJ/kg
Copper is the original—and still dominant—electrical conductor. Its high conductivity, corrosion resistance, affordability, and mature supply chains have made it indispensable for wiring, cabling, motors, and electronics.
Of the roughly 26.5 million tonnes of refined copper produced annually, nearly 70% goes to electrical applications. Copper will remain essential, particularly for high-current infrastructure, including power generation, distribution, and heavy industrial systems. Its recyclability and global manufacturing base further reinforce its central role.
However, copper’s dominance is under growing pressure. According to the International Energy Agency, existing mines and projects under construction are projected to meet only ~80% of global copper demand by 2030. UNCTAD has similarly warned that copper shortages could slow the clean-energy transition and digital expansion.
Read: We cannot adapt to tomorrow’s climate with yesterday’s materials, Part 1: Copper to learn more.
Importantly, not all conductive applications require copper. Many emerging and high-value applications—such as aerospace wiring, wearable electronics, flexible electronics, energy storage, telecommunications, and non-powertrain automotive wiring—prioritize weight, flexibility, and durability over maximum current. In these cases, alternatives like aluminum and carbon nanotube fibers can meet performance requirements while offering additional benefits.
Aluminum
Conductivity
Low density (lightweight)
High thermal expansion
Energy intensity
Annual production: ~68.5 Mt (≈20% for electrical uses)
Resistivity: 4.4 µohm∙cm
Thermal Conductivity: ~237 W/m·K
Thermal Expansion: 24 10-6/°C
Strength: 410 MPa
Density: 2700 kg/m³
Embodied Energy: 190 MJ/kg
Aluminum (the OG lightweight alternative!) is favored for its conductivity, low density, and cost-effectiveness, particularly in power lines and transmission cables (read this post to learn about the different types of cables, all using aluminum to transmit electricity).
Global primary aluminum production in 2022 was about 68.5 million tonnes, yet only an estimated 20% of aluminum usage is used for conductive purposes (e.g. wiring and cables).
Aluminum’s sustainability profile is mixed: primary production is highly energy-intensive, but aluminum is also one of the most recycled materials on Earth. Almost 75 per cent of the 1.5 billion tonnes of aluminium ever produced is still in use today. And every year, more than 30 million tonnes of aluminium scrap is recycled globally, ensuring its status as one of the most recycled materials on the planet. And thank goodness for that because the energy-intensity to produce it is mind blowing. Ed Conway, author of The Material World has a great piece on aluminum production here: The Weird and Wonderful Logic of Aluminium.
Aluminum's affordability and light weight make it a key material in applications where efficiency and cost are prioritized over absolute conductivity. Common applications include overhead power lines, where its low weight reduces structural demands, and automotive wiring in electric vehicles (EVs) to maximize range. Aluminum is also used in electronics as heat sinks and conductive coatings.
From a properties perspective, aluminum’s main drawback is its higher coefficient of thermal expansion, which can lead to mechanical stress, fatigue, or failure when exposed to repeated heating and cooling—particularly in precision assemblies or bonded systems.
Despite these limitations, aluminum will remain critical to electrification. Its combination of moderate conductivity, low density, and cost-effectiveness makes it ideal for high-voltage transmission, busbars, and large-scale electrical infrastructure, enabling long-distance power delivery with reduced weight.
Silver & Gold
Silver
Conductivity
Density
Thermal expansion
Energy intensity
Annual production: ~0.26 Mt
Resistivity: 1.7 µohm∙cm
Thermal Conductivity: ~420 W/m·K
Thermal Expansion: 20 10-6/°C
Strength: 290 MPa
Density: 11,000 kg/m³
Embodied Energy: 1500 MJ/kg
Gold
Conductivity
Density
Thermal stability
Energy intensity
Annual production: ~3,300 tonnes
**Property values below are sourced from Wikipedia because they are not included in Ashby.
Resistivity: 2.214 µohm∙cm
Thermal Conductivity: ~318 W/m·K
Thermal Expansion: 14.2 10-6/°C
Strength: 120-260 MPa
Density: 19300 kg/m³
Embodied Energy: 250,000 MJ/kg
Silver is the most electrically conductive metal known, while gold offers excellent conductivity combined with unmatched corrosion resistance. However, both are constrained by cost, scarcity, and the massive amount of energy it takes to produce them, which severely limits their use in industrial-scale applications.
Like all materials, silver and gold have their trade-offs. Silver tarnishes through oxidation and sulfidation, forming less conductive surface layers over time. Gold avoids this issue, making it indispensable in high-reliability electronics, such as connectors, contacts, and microelectronics, where even minor degradation is unacceptable. Nevertheless, both are extremely dense and lack strength.
Non-Metal Conductive Materials
Carbon-based conductive materials—most notably graphene and carbon nanotube (CNT) fibers—are increasingly important as performance requirements evolve.
Global production volumes remain small: bulk graphene production is ~0.02–0.025 Mt/year, while CNT (feedstock of CNT fibers) production is ~0.02–0.03 Mt/year, dominated by multi-walled CNTs for batteries and composites. Single-walled CNTs—the highest-performance form—represent a tiny fraction of this volume.
Where these materials diverge is scalability and broad applicability.
Graphene
Conductivity
Low density
Thermal stability
Extremely limited real-world usability
Resistivity: ~0.001 µohm∙cm
Thermal Conductivity: ~3000-5000 W/m·K
Thermal Expansion: -8.0 10-6/°C
Strength: 130,000 MPa
Density: The (two-dimensional) density of graphene is 0.762 mg per square meter. A kilogram of graphene therefore has an area of 131.2 hectares.
Embodied Energy: 264-304 MJ/kg
*Values apply to single-layer graphene, typically microns in size.
Graphene’s extraordinary properties apply only at the single-layer (2D) level, where it is just one atom thick. These properties degrade rapidly as layers are stacked. In bulk form, graphene behaves much like graphite, with electrical conductivity typically falling to 0.1–1 MS/m—far below what is required to replace copper.
While large graphene sheets can be produced, scaling them while maintaining pristine, defect-free quality remains a major challenge. Claims of ultra-high thermal conductivity (3,000–5,000 W/m·K) refer to suspended graphene, which is not relevant for practical applications.
As a result, graphene remains best suited for niche applications, including sensors, flexible displays, and certain energy-storage technologies, rather than large-scale conductive infrastructure.
Galvorn®
Conductivity
Extremely low density
High strength and flexibility
Lower energy intensity
Resistivity: 10 µohm∙cm.
Thermal Conductivity: ~450 W/m·K
Thermal Expansion: ~0 10-6/°C
Strength: 3000 MPa
Density: ~1.6 g/cm³
Embodied Energy: 47 MJ/kg*
*Source: ARPA-E funded research done in collaboration with Rice University and Shell. 47 MJ/kg is the projected embodied energy for Galvorn produced at scale.
Note: Galvorn properties have been measured in-house, as well as validated by customers.
Galvorn® is the lightest, strongest, and most flexible conductive material available today. Unlike graphene, Galvorn is engineered for industrial-scale applications. It is a great option for wire and cable applications, maintaining high-performance properties even at the macroscale.
Critically, Galvorn offers a combination of performance advantages that free engineers and designers from traditional material tradeoffs. In addition to being conductive, it offers significant lightweighting—it is approximately 80% lighter than copper and 96% lighter than copper-based EMI shielding—with exceptional durability, being about 50 times stronger than copper. With its carbon-fiber-level strength, textile-like flexibility, and extremely small bend radius it also allows for tighter routing and more efficient use of space. Bottom-line: Galvorn offers a lighter, stronger, more efficient alternative to metals.
The advantage of Galvorn, however, is not just about properties. It’s about scale and scalability. Unlike high-performance graphene, which is limited to niche applications by the nature of its single-layer form factor, Galvorn yarns / wire and films are macroscopic form factors that can drop into traditional metal-based applications.
Watch the Galvorn demo video:
Technology, energy, and materials are inseparable.
Copper and aluminum will remain foundational to modern life—but as demand for conductive materials accelerates and supply constraints tighten, material optionality becomes essential.
Galvorn® does more than fill a gap. It represents a platform technology that enables lighter, stronger, more efficient systems—helping engineers do more with less, and reshaping how we think about conductivity in the decades ahead.