Copper vs. Aluminum Busbars: 8 Key Differences and How to Choose Which One Is Right for Your Application

Last updated on July 30th, 2024 at 09:57 am

While busbars have become the go-to option for electricity distribution across a range of industries, it can be difficult to know which busbar material is right for your application. Should you opt for copper, which boasts higher conductivity, ampacity, and strength? Or would aluminum busbars be a better fit, thanks to their lower weight and cost?

To answer these questions, let’s dive into the key differentiators between copper and aluminum busbars and explore how to determine which type is best suited to your project.

8 Key Differences Between Copper and Aluminum Busbars

Before deciding on which material is right for your project, it’s important to understand the eight key differentiators between copper and aluminum fabrication for busbars.

1. Conductivity

Copper has higher electrical conductivity than aluminum, with roughly 58 MS/m (mega siemens per meter) versus the 37 MS/m found in aluminum. Copper busbars carry more current with less resistance, which can result in more efficient electrical systems.

Winner: Copper ✅

2. Ampacity

Thanks to their higher conductivity, copper busbars tend to have higher ampacity than aluminum busbars of the same dimensions. In practice, copper busbars’ conductivity allows them to carry more current without overheating.

Winner: Copper ✅

3. Strength

Copper is denser and has a higher tensile strength than aluminum making copper busbars more resistant to mechanical stress and deformation. Therefore, copper busbars can create more durable and reliable electrical connections. Still, if properly designed and fabricated, aluminum busbars can also be adequately strong for many applications.

Winner: Copper ✅

4. Corrosion resistance

In most environments, copper is more resistant to corrosion than aluminum. That said, aluminum can form a protective oxide layer, which can help prevent further corrosion in aluminum busbars for many applications.

Winner: Copper ✅

5. Thermal expansion

Aluminum has a higher thermal expansion coefficient than copper. For this reason, aluminum busbars might expand and contract more with temperature changes, which can lead to unstable connections and even mechanical failures. Copper busbars, on the other hand, generally have longer lifespans and lower maintenance costs thanks to their superior corrosion resistance and mechanical strength.

Winner: Copper ✅

6. Weight

Because aluminum is less dense than copper, aluminum fabrication delivers busbars that are lighter than copper ones of the same dimensions. Because copper busbars are heavier, they can be more difficult to transport, handle, and install.

Winner: Aluminum ✅

7. Cost

Aluminum is generally more affordable than copper, making aluminum busbars a better choice for large-scale applications where cost may be an issue.

Winner: Aluminum ✅

8. Availability

In some regions, copper may not be as widely available as aluminum, which can lead to longer lead times and higher procurement costs.

Winner: Aluminum ✅

Choosing the Right Busbar Material for Your Project

Ultimately, making the choice between copper and aluminum busbars will depend on the specifics of your given project or industry, including application requirements, budget constraints, and environmental considerations.

When to use copper busbars

• High-performance electrical systems: If your project demands high conductivity and low resistance, such as in high-performance electrical systems (e.g., applications in power generation, transmission, distribution, and high-power electronics), you’ll likely want to opt for copper busbars.
• Critical infrastructure: Copper busbars are great for critical infrastructure projects where reliability and longevity are paramount, including substations, data centers, telecommunications facilities, and industrial plants.
• Harsh environments: If your application is in an outdoor or corrosive environment where busbars may be exposed to moisture, chemicals, or extreme temperatures, copper may be your preferred material, thanks to its heightened corrosion resistance and durability.
• Low-resistance connections: Copper busbars may be right for you if your project demands low-resistance connections, as is the case with high-current applications, motor control centers, switchgear, and power distribution panels.

When to use aluminum busbars

• Cost-sensitive applications: Aluminum busbars tend to be the better choice for projects where cost is a central concern.
• Lightweight applications: In sectors where weight is a core issue-such as the aerospace, automotive, marine, and portable electronics industries-lighter aluminum busbars tend to be the better option.
• Applications requiring heat dissipation: Aluminum busbars dissipate heat and prevent overheating better than their copper counterparts.
• Flexible applications: Aluminum’s malleability allows for easier fabrication and bending compared to copper, marking aluminum busbars as the better choice for applications where flexibility is paramount, such as in busway systems and bus ducts.
• Utility-scale power systems: For utility-scale power systems, such as solar and wind farms, aluminum busbars tend to be the industry standard due to their low cost and suitability for high-voltage transmission and distribution.

ASM Can Fabricate Copper and Aluminum Busbars to Your Specifications

As experts in custom sheet metal fabrication, we know that choosing your busbar material is just the beginning. When it comes to copper and aluminum fabrication for busbars, ASM employs turret punches, laser cutters, and press brakes to ensure precision and customization. These machines allow us to fabricate precision sheet metal busbars to the most detailed of specifications-all while minimizing costs and lead times.

Ready to get started on your next busbar project? Request a quote today!

Copper vs. Aluminum Busbars FAQ

What are the main differences in electrical conductivity between copper and aluminum busbars?

Copper busbars have higher electrical conductivity, approximately 58 MS/m, compared to aluminum’s 37 MS/m. This means copper busbars carry more current with less resistance, making them more efficient for electrical systems.

How does the strength of copper busbars compare to aluminum busbars?

Copper busbars are denser and have a higher tensile strength than aluminum busbars. This makes copper more resistant to mechanical stress and deformation, resulting in more durable and reliable electrical connections.

Why might aluminum busbars be preferred in certain applications?

Aluminum busbars are preferred in applications where cost and weight are critical factors. Aluminum is more affordable and lighter than copper, making it suitable for large-scale projects and industries such as aerospace, automotive, and marine.

In what situations are copper busbars more advantageous?

Copper busbars are more advantageous in high-performance electrical systems, critical infrastructure, harsh environments, and applications requiring low-resistance connections. They offer superior conductivity, strength, and corrosion resistance.

What factors should be considered when choosing between copper and aluminum busbars for a project?

Factors to consider include the specific requirements of the application, budget constraints, environmental conditions, availability of materials, and the importance of weight and cost. Copper is ideal for high-performance and critical applications, while aluminum is better for cost-sensitive and lightweight applications.