Commonly Used Solar PV Wire Types and Installation

Solar photovoltaics is a revolutionary technology that has provided an alternative means for clean and sustainable energy production. Considering the environmental impacts of conventional fuel such as, coal and oil, solar energy has acted as nothing less than a boon for the health of the planet. Increasing the number of solar energy device installations has helped the evolution of this technology to increase efficiency at a steady pace. Like all electrical equipment, the efficiency of these solar devices depends highly on the quality and deftness of the wires installed within the equipment. In this article, you will get to learn about the commonly used solar PV wire types and their installation methods.

Types of Solar Photovoltaic Wire

Type #1: Metals

Metals that are good conductors of electricity, like copper and aluminum, are generally used for wires wherever residential and commercial solar photovoltaic installations are concerned. Relatively speaking, copper is better at conducting electricity than aluminum; however, being the costlier of the two metals, aluminum is the one widely used. Where energy efficiency is of prime importance, copper wires are installed. Aluminum wiring is mostly used for underground or overhead installation in solar photovoltaics.

Type #2: Solid or Stranded

Wires can either be solid or stranded (still being made out of metals as described above). Solid wires are simple comprising of long strands of solid metal. Stranded wires, however, are a twisting jumble of many thin, long strands of metal, making it look like a braiding. Stranded provide better flexibility than the solid wires. The risk of breakage and corrosion is also remarkably less among stranded wires. An additional benefit with stranded wires is that they carry the current over their surface, which makes them more efficient.

Installation of Solar Photovoltaic wire

There are certain color codes that are used in solar photovoltaics to determine the function of each wire in the installation. For all AC (alternating current) installations, green/bare wires represent equipment grounding, white wires represent a grounded conductor whereas black or red (or any other color) represent un-grounded hot equipment.

For all DC (direct current) installations, red wires represent positive node, white wires represent grounded conductors or negative node, and green/bare represent equipment grounding.

In addition to this, there are certain codes that specify the characteristics of solar photovoltaic wires:

• THHN – Heat resistant thermoplastic wire
• THW – Moisture and heat resistant thermoplastic wire
• TW – Moisture resistant thermoplastic wire
• UF and USE – Underground feeder and branch circuit cable single conductor

Selecting the right PV wire for your installations can greatly improve efficiency.