Perhaps you've seen a skydiver or hot air balloon come dangerously close to hanging in them.
And you would have to be blind to have never seen birds sitting on the wires either. However it wasn't until now I thought this was actually a major problem affecting power supply and really endangering the lives of our avian cohabitants.
Well, according to the IEEE it is - and once you think about it from both an environmental (biodiversity and wildlife protection) and energy stability perspective, you can see why two new IEEE standards are needed.
The power engineering standard IEEE 1651 outlines "methods, techniques, and designs to mitigate bird-related power interruptions and equipment damage resulting from avian interactions with electric facilities. The standard addresses a wide range of situations, including electrocutions, collisions, nesting problems, and outages caused by fecal contamination and fecal streamers. Topics include bird impacts to transmission lines, distribution lines and substations, as well as woodpecker issues."
The second standard IEEE 1656 guides manufacturers with designing, installing and testing wildlife protection devices installed in overhead electrical distribution systems.
Its funny the stuff you come across late at night sometimes...