Importance of Electrical Conduit for Underground Lines

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I came across an interesting article that describes the importance of using electrical conduit when undergrounding power lines.  Yes, using conduit is an obvious step, but the article goes a little deeper into the whys and how’s.  Granted it is sponsored content, but it is educational, nonetheless.

Electrical Conduit 101

Simply put, electrical conduit protects underground power lines by encasing them, including protecting them from roots and other types of underground vegetation, damage from animals, and erosion and general degradation over time.  According to the National Electric Code (NEC), lines should be buried at least 18 inches deep ? but in some cases could be buried up to a whopping 12 feet!

As for material, there are plenty of options, some of which are better than others.  These include polyvinyl chloride (PVC), fiberglass, galvanized steel, and rigid metal.  According to the article, fiberglass is the best choice for several reasons:

• It offers high dielectric strength.
• It offers low coefficient of friction, so fewer pull boxes are needed.
• Installation is easy and cost effective.
• It has a high resistance to electrical faults – if a fault does occur inside a fiberglass conduit, the impacted cable just needs to be removed, and then the conduit can be reused because it will not melt.
• It is resistant to corrosion and general degradation – fiberglass can hold up against a wide variety of chemicals and other underground hazards.
• Extreme weather protection – the material can function properly in temperatures ranging from -60 degrees F to 250 degrees F.

All in all, this is good information to know because overhead wires are increasingly at risk, especially in the western half of the U.S.  Wildfires, windstorms, tornados, and other extreme events can destroy wide swaths of overhead infrastructure, but underground lines are largely immune to the impact of these types of extreme events.

That said, even underground lines must be protected, and fiberglass electrical conduit seems like the optimal solution.