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Comment by mkagenius | Hacker News Reader

As an inventor how does one convince oneself to allow overhead wires carrying life threatening currents or any other such inventions. There exists so many inventions I would never pursue even if it occurred to me first, yet they exist and make our lives better.

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No inventor sat down at a blank slate and said "Hey, let's string 700KV power lines across the country on huge towers".

Overhead powerlines developed gradually from an overhead line running power from one side of someone's lab to the other, to power running between buildings, to city wide distribution and beyond. As time went on, the powerlines got larger and higher voltage.

There aren't a lot of options -- underground powerlines are possible, but they have their own disadvantages so are not a clear-cut winner.

One also has to take account the historical context. When humanity started to use electricity for practical applications (ie. telegraph) there was no practical alternative to overhead wires isolated by ceramic bushings and air. Reasonably low-cost and durable cable insulation materials were invented around the WW2.

I suppose someone figured that, after a point, the only question is how far your red mist will be spread should you have contact with a line. I mean, I'll put money on the fact that you're sitting in a room right now with nearly-exposed electrical contacts that can kill you. I guess it's not a great leap from there to "go ahead and hang them overhead, and try to make sure they won't fall down".

OTOH, the only thing I've ever seen take down high tension towers was an ice storm so bad, they collapsed under the weight.

Yeah overhead on a strong tower is probably the best place for them. Underground they're way more likely to get hit accidentally and if the shielding failed it'd be impossible to tell where the danger was from the surface without specialized equipment.

underground is more resilient to damage but harder to do maintenance and actually much more expensive at the distribution level

It would also increase the cost a lot due to the digging and actually requiring insulation that will hold up where the overhead lines are bare aluminum insulated by air.

Exactly. It's mostly cost that keeps underground transmission lines limited to very specific situations. I forget the exact figure, but underground transmission is something like 20x the cost of above ground.

A lot of pylons went down during the 2016 South Australian blackout, no ice required.

https://www.google.com/search?tbm=isch&q=2016+South+Australi...

"The strong winds and lightning strikes look to have damaged power transmission towers"

ahem, I never said that only ice was required. But those towers didn't just fall over on a calm summer's day. :-)

It happened here in 1998 in Montreal, Quebec

It did cost over $2B to rebuild the network.

https://www.cbc.ca/news/canada/montreal/ice-storm-1998-1.446...

What's the alternative. Burying them is arguably more dangerous because the insulation failing would make the area immensely dangerous with no obvious signs. The power needs to get from generation to consumer somehow and high voltage lines are good for long distances.

Can someone explain to a software person why this wouldn't basically just ground the power?

At the voltages involved in power transmission the "grounding" will cause an arc that'll do a lot of damage and take the transmission line out of service until it's dug up and fixed. And that takes awhile and costs a lot of money not to mention lost revenue while the transmission line is out of service.

Above ground is the way to go since it's cheaper to construct and much easier to service when things go wrong.

Grounding doesn't make the electricity magically disappear - for large voltages and currents, it's difficult to dissipate.

For example, if you'd simply stick a high voltage line into the ground, then there would be a voltage gradient between the ground voltage far away and (almost) the line voltage directly at the place where you stuck it; and since the earth isn't a very good conductor (compared to e.g. yourself), if you walk towards it, then the "step voltage" between your leg closest to the wire and the other leg can be sufficient to kill you.

If you do ever find yourself in that kind of situation (powerline draped over vehicle or similar), solution one, the way to go, is "don't exit the vehicle".

That being unavoidable (vehicle on fire, etc.), don't walk away from the vehicle, jump, two feet at a time, and keep jumping that way, until you're a good distance away. This avoids you ending in a situation where you have that step voltage between the voltage rings.

For an incredible read about just how bizarre fixing underground power distribution can become, check out this classic: https://www.jwz.org/blog/2002/11/engineering-pornography/

Here's the tl;dr version: https://hackaday.com/2015/07/27/find-and-repair-a-230kv-800a...

Haha a jwz link those are great.

For those that don't know, you can get around jwz's referrer redirection by opening the link incongnito.

Make sure you copy and paste the jwz link, just clicking it redirects to an imgur picture.

I never knew I could be enthralled by a faulty power line. What a story!

Unfortunately cost would have been a factor. High voltage, low current is going to lose less in transmission so it’s hard to justify a less dangerous option if it means paying way more to make up for wasted energy.

How do you feel about automobiles, then? Lot more deaths from cars than from power lines

Oh, I am not saying they are bad (overall). Just that, if it didn't exist before then I would never be able to convince myself to pursue doing that.

More importantly I want to understand how to let go of such inhibitions (and thoughts) of not pursuing such ideas..

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