Turbine more than earns its keep | Rural

It may not be big enough to put the wind up the giant turbines parading on the hills behind Palmerston North, but the wind turbine that's gone up on a farm near Wanganui could be the way of the future.

The 10m-tall turbine was made in China and took about a week to install on Alan Taylor's farm at Westmere, just north of Wanganui city.

Taylor, chairman of the Wanganui district rural community board, says the practicalities of having a wind turbine on a fairly exposed part of the farm makes sense.

"I used to think wind turbines were visual pollution, but it's not burning coal or natural gas. And there's a limit to how many rivers they can dam up."

The process of power production by the three-bladed turbine is simple: the power generated by the 10kW turbine is fed directly into the national grid. The Taylors draw their power from that grid just as other power users do but their household uses less than the turbine generates so they enjoy a net gain.

That excess is what the power company - in this case Meridian - will pay back to the Taylors.

Taylor has put the cost of the turbine and installation at between $70,000 to $100,000 and he reckons it will pay for itself within a decade.

"If we turned on everything in our house, and that includes the two heat pumps, we'd probably used about 6kW to 7kW an hour at the very most."

Although some of that installation involved a technician from China, the wiring to the meters and converters in a nearby shed was done by local electricians.

The turbine is the biggest "domestic" wind turbine that can be installed - anything bigger is regarded as a commercial installation.

There is a small sensor aerial on top of it which recognises the wind direction and signals the turbine to point into the prevailing wind. It can rotate 360 degrees to harvest the wind from any direction.

The speed of the big fibreglass blades is governed so it can't overspeed and a brake is applied automatically to keep the machine's speed in check.

There are other failsafe processes as well. If too much power is being generated for the national grid then the turbine won't start operating.

Taylor says he is a "little disappointed" because, unlike Britain, where five-year supply contracts are available, New Zealand power companies are not keen on going beyond a normal billing cycle.

He says the deal offered by Meridian is the best on offer.

Although he needs to get a building consent he has not needed a resource consent for the turbine.

"The district council said we only needed to get the okay from a couple of neighbours to say they were happy with the turbine being there and get them to sign a letter, because the turbine was under a certain height."

"Then the council chief executive contacted me and said we were the only near neighbours that needed to be considered."

He says the problem for the council is that there has been no other turbines like it in the district so there is no precedent.

"But I think this might now be something they will be considering in their district plan because there are going to be more of them probably."

The turbine has generated a fair amount of interest and a neighbour is considering using one because of the amount of electricity they use in their cowshed.

Taylor says he would recommend the turbine to others because they are a clean green alternative power generator.

"The more people can do this the better, I believe.

"The big thing is they're not cheap and it might take you 10 years before you get the payback and a lot of it comes down to the power price."

But he says he will be more comfortable with a long-term contract.

"There's nothing to lock the power companies into that sort of contract and I'm a little uncomfortable with that. It's not too critical if you're only producing what you use but does become an issue when you're making surpluses."