The great power burial

In many new areas, powerlines are going underground. But if you live in an older area, would you fork out for the privilege?

A paper released last year by the Crawford School of Economics and Government at the Australian National University found that underground powerlines could increase a home’s value by 3 per cent. That doesn’t sound much, but on a $500,000 property, it equates to $15,000.

It’s not really an issue I’d considered until I moved house recently where a hedge had been inconveniently planted under some low-hanging powerlines. After getting the tree trimmers in for a fairly decent sum, it occurred to me that in the long run, it would be easier to either rip out the hedge and plant something more appropriate, or get the powerlines buried underground.

Given how long hedges take to grow, it seems more sensible to opt for the underground option.

At the same time, the local council is planning to tear up the existing footpath and lay a new one, so I wondered, would it be possible to lay the powerlines underground at the same time? That would reduce fears in storms of live wires coming down, and also cut down on the need to butcher street trees growing around powerlines.

Many new areas now have everything underground, and it’s easy to see why councils are forcing developers to go down that path. Although overhead set ups are seven times cheaper to install than the sub-ground option, they are also a lot more susceptible to storm damage in high winds. Or even just a tree branch coming down in normal weather and taking out half a suburb’s power.

On the downside, as Energex found out in the recent Queensland downpour, underground wires don’t much like floods. “Underground cables are laid in pipes, in conduits, and they really act more as a funnel for flood waters,” a spokeswoman says.

If something goes wrong, it can take a lot longer to find and fix the fault. “You have to dig up the earth to be able to repair anything, so it’s go its inherent issues. It was definitely more difficult for us to restore power to those underground areas [during the floods],” the Energex spokeswoman says.

Perth has been putting existing powerlines underground since 1996 and is somewhat of a world leader. About half of the city’s homes now have underground power, helped along by a policy for all new estates to have underground infrastructure, as happens in many other parts of Australia too.

The impetus was some terrible storms back in 1994 that brought powerlines down and left many people without power for more than a week.

Tony Moore, a spokesman from energy supplier Western Power, says putting existing cables underground costs between $10,500 and $11,500 per home. In south-west Western Australia, local councils foot 50 per cent of that cost, while the power company and the state government each cough up one-quarter.

Western Power works on a per lot basis, but some of the lots are strata title, which means councils can collect one, two or more rates for that “lot”.

By the time councils take that into account, and sometimes inject a bit of extra funding, undergrounding existing wiring usually costs ratepayers about $4500 per property, Moore says.

Because the maintenance costs of underground powerlines over their nominal 40-year life are about 20 per cent of their initial installation cost, that split makes it equitable for Western Power to support the project.

But if Western Power had to pay for all of the undergrounding costs, the return on investment wouldn’t make sense, Moore says.

“In Perth we’ve been able to build a program that has encouraged people to be accepting of the fact they’ve got to pay $4000 – $4500 to get underground power. But I can tell you that when they get it, they love it. They support it in droves,” Moore says.

Surveys at the end of each project show satisfaction levels in the high 80s to early 90s, which means people often change their attitude once they see what a difference the underground wires make.

“You might have done a survey during the project to see whether they’re prepared to pay for it or not and in some cases you don’t even get 50 per cent, so we can’t do a project,” Moore notes. “It’s never forced on people, it’s always given to them as an option but if they’re not prepared to pay the money then we won’t go ahead and put Western Power and government money into areas that are not prepared to support it.”

Nevertheless, the hope is that one day, all of Perth’s power will be underground.

“The reliability levels are markedly improved where we have converted them from overhead to underground,” says Moore.

The work is done through drilling, not trenching, so while there’s still a bit of mess, it doesn’t make the street look like Armageddon. And at the end there are no poles or lines visible.

Would you pay to have your powerlines put underground? Or do you think, given all the other worries at the moment with rising power bills and cost of living pressures, it’s a non-issue?

Carolyn Boyd,

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