Aluminum and copper are some of the most widely used materials for electrical wiring. Both materials work great, but they have a few key differences you should know when choosing between the two. Below are some of the major areas in which aluminum and copper differ.
Copper is heavier than aluminum; copper can weigh as much as 70% more than aluminum. This may not mean much if you are handling only a few feet of electrical wires. However, the difference is significant for extensive electrical installations that involve thousands of feet of wires. In such a case, dealing with the aluminum will be easier since it is lighter and easier to haul around than copper.
Cost is usually a factor in most electrical projects. In this regard, aluminum has an advantage over copper since it is significantly cheaper. Although the actual price of the metals fluctuates over time due to various forces, copper prices always manage to say ahead of aluminum prices. Again, the difference might not mean much if you just want to replace a cable or two. However, the difference can add up to significant money in the case of an extensive electrical project.
Thermal expansivity is the tendency of materials to increase in size when subjected to a temperature increase. Both copper and aluminum expand when heated. However, aluminum expands much more than copper. The expansion can be a bother, since it can loosen electrical connections if the temperature increase is significant. Not only that, but the constant expansion and contractions due to temperature fluctuations also weaken the metal over time; in this case also, the aluminum conductors will be more affected than the copper conductors.
When it comes to toughness, copper has an advantage since aluminum is softer and easier to nick. This can be a problem in tough environments where different materials have to share spaces. Even when installing or repairing aluminum wiring, you have to be careful so as not to nick or dent the aluminum. Otherwise, the damage will increase the electrical resistance of the material, which can lead to overheating and electrical damage or fire.
Rust and Corrosion
Most metals rust, including copper and aluminum. However, copper still has good conductivity if it is rusty, while aluminum loses most of its conductivity when it rusts. Reduced conductivity, as explained above, is a safety risk, since it can lead to overheating of the affected conductors.
Both metals are used in electrical wiring depending on the priority of the project owner, the scope of the work, and the nature of the installation environment, among other factors. Your electrical contractor from a company like Dunedin Electric Co., Inc. will analyze your project and advise you on the best metal for your case.