Do Electric Companies Replace Their Equipment in a Timely Manner to Protect the Public?

When power utility installations and equipment are new, there are initial failures related to both design and manufacturing deficiencies, similar to a new car that malfunctions or is subject to recall.

Engineers call this the “bathtub curve” cycle. During the cycle, there’s an initial break-in period necessary to get all of the glitches out, followed by a long period of relatively low failure, and eventually a notable upswing of failure rates as systems age. In other words: A break-in period, a useful lifetime, then a wear-out period.

Engineers who design power line structures use the “bathtub curve” to analyze and predict equipment failure. And power companies are supposed to use this information to protect the public from electrocution and injury by inspecting and repairing the structures.

But power companies often try to extend the life expectancy of their infrastructure beyond the breaking point that’s predicted by the bathtub curve — because it saves them money. And it’s the public who pays the price when they’re exposed to electrocution injuries and death by power lines.

Plotted on a graph, with the “Y Axis” representing the failure rate per year, and the “X Axis” representing the component age in years, the shape of this cycle resembles a bathtub: