Bury Power Cables Down Under?

"Although Langborek didn't cite costs" Nuff said.

Burying high voltage transmission lines is expensive.

There is a trend in new housing estates here in Oz, to run all the services underground, it will take some time before the HT lines get run underground for technical reasons. Though undergrounding powerlines does not protect it from flooding...

The main benefit is in the street scape, although there are still street light poles.

As for the NBN (Not Bloody Needed), its merely an expensive monument to the prevailing governments wanton waste of finances to top the other extravagant monuments to wasteful spending. Hopefully we can have regime change before too much is implemented. When the prodominant demand for new internet connection is wireless, why persist with inappropriate outdated technology? Unless you want to create a monopoly on internet access.....

What a bloody non sequitur from the representative. What the hell does any of them knows of economic or technical tradeoffs? Zip, nada, nothing.

Do your own calculations, you will be wiser, than any of these blowhards. This "I would have water than oxygen" quotes are noted just for their inane stupidity.

It took a week to get power back on after Cyclone Yasi. That's OK. This Island is made of granite so under ground could just not be implemented, for cost reasons.

If all foliage is up and running power lines become close to invisible. It's horses for courses and going underground could be beneficial in some areas.

The third world has no choice and that is most of humanity!

We are spoiled for choice, Ky.

In the run up to he London Olympic Games two 6Km sections of 400Kv power lines were buried in tunnels under the site. The original cost estimate was £250million, during construction this increased to over £300million (some unconfirmed estimates put it at £330million). London clay is not a difficult material to tunnel through compared to granite or limestone criss crossed with water courses. £20-25million pounds per Km reflects that this was a one off. If you were undergrounding a whole network this cost could probably be reduced to an average of £10million per Km, compared to just under £1million per Km for overhead lines. Estimates for undergrounding compared to overhead lines vary significantly depending on terrain, but a ratios of 11:1 for 400Kv lines down to 4:1 for 32Kv lines are typical. Find out how much the Queensland network cost to install, update that cost to contemporary prices, then multiply by eleven. But have some sedative handy because the final figure will make your head spin.

One of the main arguments for putting power lines underground is that they are less susceptible to weather damage. True but faults that do occur are harder to find and take longer to repair. Flash floods are more common in Queensland than the recent extensive flooding. These are more likely to cause disruption to supply, either by pylon or underground, than a slower moving mass water. So is the end user any better off? Not if the utility companies have to recover there capital costs in higher bills.

Living in scenery free of ugly power lines is OK, if anybody can afford to live there.

What size of power lines are they referring to? Local infrastructure that is typically under 10KV phase to ground, intermediate levels under 100KV phase to ground or the big interstate ones that push into the multi hundred KV levels?

The lower and intermediate power lines are already capable of being buried underground where ever the terrain and soil conditions allow so there is no real issue or problem with that other than there is a higher initial installation cost. However that installation cost does get offset over the long run by the generally lower overall maintenance costs that add up over the life of the line.

Where I live the local distribution system has been largely converted over to underground with much of it having been in service for nearly 20 - 30 years now and it has become well respected for being reliable and storm proof and low maintenance.

This is one of the dumbest apples-vs-oranges questions I've ever heard, even given the lot of formulaic fluff on this side of the daily page. At least burying cables down under will be easier than burying them up over.

In my opinion, this is a tough call. Keep the lines on the poles, weather will take them down, put the line in the ground, weather will take them out and possibly cause a bigger event due to flooding. I believe there is one good answer, but unfortunately the man working on this idea I think was fried too many times and died a lonely old man. His works are yet being discovered as he kept few notes. Maybe one day we will have wireless electricity to every home in the world. Till then I guess our best hopes are aerial still.

I am not sure where this concern over flood damage to underground power lines comes from. They are designed to be underground so that means they are capable of being wet also.

The service boxes are typically setup with all live connections sealed air tight so that in the event of getting wet they have no problems being fully submerged while still being operational. As far as crossing waterways with underground lines it is also standard practice to use a horizontal boring setup and bury them much much deeper below the active water channel than what the normal underground run is buried at which eliminates any problems from possible erosion issues. If they cant be buried underground then a short overhead pole mounted run is used.

Relating to substation design its also standard practice to build up the substation pad to a level above that of the surrounding land to further prevent possible flood water related issues.

None of this is difficult civil or electrical engineering principals to figure out or deal with.

Get your Liberal political agenda out of this...focus on the real engineering issue and do some research as to pros/cons of underground power cabling.