Brian Rudman: All power to pylon options

Listening to the wails from the Waikato about Transpower's proposed national electricity grid expansion from Whakamaru north across farmland to Otahuhu, there are times when you'd think Aucklanders were behind it all.

So it was pleasant on Saturday to read Clevedon activist Colin Bull pointing the blame where it lies, at Transpower, and calling on us, his urban neighbours, to join the rural community "in our fight against tyrants who will trample over us".

For a died-in-the-wool old Tory like Colin to succumb to such socialist fighting talk, things really must be dire and I'm happy to dust down the red flag in his support. If he can come up with an alternative, I'm sure most Aucklanders will back him. After all, who in their right minds, wants more ugly pylons marching across farmland or the outskirts of suburbia?

But if not pylons, then what?

One of the worst aspects of this debate is that the state-owned enterprise is pushing a one-option solution, rubbishing alternatives, and warning if we dither, Auckland will be risking power cuts by mid- 2010. It's hardly the ideal circumstances for informed debate.

Opponents want an underground route, which Transpower says is technically inefficient and will cost up to nine times more. This recalls Transit New Zealand's argument for cutting through the side of Mt Roskill and over Victoria Park, and former mayor John Banks' dream of a highway across the eastern suburbs.

In all, the engineers downplay any costs not directly connected with the construction of their dream. The cost to the environment, for one, and the costs to the citizens affected.

You only have to look at the pylon design to get a feel for Transpower's priorities. A sexy 21st century-styled pylon may not have seduced those immediately affected, but it would have shown the engineers had some feelings for the world about them.

I'm not naive enough to imagine that compulsory cold baths or wind farms on the Manukau Heads will obviate any need to upgrade the national grid. At best, it might delay it for a few years. But I do believe we need an independent body, perhaps the Electricity Commission, to offer some well-researched alternatives, so we can have better-informed debate.

Transpower discredits undergrounding on technical and cost grounds. The arguments read like those against running highways through tunnels. In recent months, Transit has begun to bow to public pressure and agreed to accept more expensive options, undergrounding under Victoria Park, for example, or tunnelling under bush on the Alpurt B highway rather than carving an ugly cutting through the middle of it.

Undergrounding is not the only option. Transpower also commissioned engineers Maunsell Ltd to examine a proposal to lay cables along the Waikato River bed.

Maunsell's, who concede "our experience in submarine cable engineering is relatively minor", say the river cable idea "appears impractical". And that's without going into the cultural complications like upsetting taniwha.

They argue that each of six cables would have to be secured in a separate trench, each two to four metres apart. Then there's the scouring, the four dams to get over and the risk of broiling the wild life with leaking heat. About the best they can say for this route is that at 210km, it is "surprisingly direct".

They conclude it "has some serious disadvantages compared with burial in a road route such as the state highway". Which raises the question, why not the state highway as an alternative? Either above or below ground?

Another possibility could be to transfer the national grid offshore. Auckland's South Island power already comes in the direct current form used in submarine cables from Waitaki, overland to Cook Strait, then under the water to the Hutt Valley where it is converted to alternating current for the rest of its journey.

Why not extend this cable offshore to the Manukau Harbour and Otahuhu? Undersea power cables are planned, or in operation, between Britain and Norway, Canada and California and Canada and New York.

Colin Bull wants Transpower to go back to the drawing board. But with Transpower's hat firmly hung on the pylon solution, what's needed is an independent inquiry into all the options.