The Friday Blog
When the power company send electricity out of it’s plant through all those lines and to your home, it must end out enough juice to overcome the resistance of miles and miles of cable. The greater the current, the greater the resistance. In order to get around this obstacle, the power company sends out electricity in a low current, but extremely high voltage way. This reduces the “drag” from the power lines and allows you to get more of the sent electricity. (The utility still typically loses 3/4 of it’s electricity due to cable resistance.)
However, homes are run on low voltage, high current electricity, so what your utility send you must be converted before it goes into your house. Thus the transformer. Typically located in a box or canister on a pole at the street, transformer convert the electricity to a form you can use. (The process is actually quite simple… but not really critical to where we’re going.)
Transformer can explode when they get a massive spike in current, like from a lightning strike. There is a shut-off switch intended to protect the mechanism which is almost entirely superfluous, as it cannot possibly shut off fast enough to stop the internals from critically overheating… plus, it does nothing to stop the rest of the device from building up pressure and heat which will end in exactly the same result. (Transformer design and production were deregulated and modern products are notoriously cheap, unreliable, and failure-prone.) But the best bit is that transformers use a highly refined and flammable mineral oil as a coolant for the heat-producing conversion mechanism, providing the accelerant for the bomb when things go awry. It is this pressurized oil that makes the beautiful explosion and terrifying boom when a transformer blows up.
Recently lightning has been taking a back seat to squirrels as the number one cause of catastrophic failure among transformers as oak trees have been producing more acorns, and thus more squirrels. (Climate change maybe? I don’t really know.) Squirrels chew through insulation, run along connections, use their furry little bodies to complete circuits that ought not be completed. Individual utilities spend millions of dollars annually on squirrel-related incidents, and in the wrong spot, one rodent can wipe out the grid for as many as 60,000 people.
Yesterday morning a suicide terrorist squirrel threw herself on the electrical connections of the transformer outside my home and took out a total of three of the things. The repair crew came out and said the whole thing was fried and left to go get replacements. It took most of the day to get everything back up and running.
Sadly, we have no idea what the squirrel’s agenda was, or what point she was trying to make, beyond the sowing of terror. Though I wish her people no ill will, I’m giving a wide berth to the oak trees.