November 7, 2007
New Zealand

Capacity of grid in doubt

Windpower is blowing up a storm between South Island electricity generators over use of Transpower’s electricity transmission lines.

At issue is whether Transpower’s links within Otago and from Benmore through the Cook Strait cable to Wellington can handle electricity generated by two proposed wind farms the TrustPower Ltd Mahinerangi project and the Meridian Energy Ltd Project Hayes and other mooted southern South Island generation schemes.

Yesterday, Transpower admitted there could be constraints, depending on the amount of electricity produced, but added if that occurred it would look at upgrading.

The debate is being led by another South Island electricity generator, Contact Energy Ltd, which said yesterday it had not yet received an official copy of the Project Hayes consent, and had not made a decision on whether to appeal it to the Environment Court.

It had appealed TrustPower’s Mahinerangi wind farm on the basis of the effect on electricity transmission.

But Contact communications manager Jonathan Hill emphasised his company was not opposing the granting of resource consents for both projects.

It wanted a condition that stipulated that as the new generation came on stream, there was sufficient capacity in Transpower’s grid to match it.

Contact was worried that, under the Government’s energy strategy, wind power electricity got priority on the grid and it would have to spill water from its Roxburgh and Clyde hydro schemes, wasting generation.

New generation had to be supported by transmission upgrades that would allow all of the energy generated to be freely delivered to where it was needed, Contact said.

TrustPower’s community relations manager, Graeme Purches, said Contact’s appeal was commercially and market-driven. He was confident that during mediation, before the Environment Court heard the appeal on the Mahinerangi wind farm, the conflict between the two companies could be settled.

TrustPower’s view was that Contact could manage its generation to avoid spilling water.

‘‘We operate our generation in a responsible manner and we don’t create constraints,’’ Mr Purches said.

He suggested Contact was ‘‘playing a political game’’ in the hope of forcing the Government to ensure the link was upgraded if potential sustainable generation was going to waste by spilling water.

Transpower communications manager Rebecca Wilson said if Project Hayes was generating 150MW to 200MW of electricity, the South Island grid was ‘‘reasonably secure’’. More than that would constrain the grid.

However, if Project Hayes was generating 600MW or more from its full 176 turbines, then Transpower might need to look at an upgrade.

Meridian chief executive Dr Keith Turner was unavailable for comment yesterday.

At the time Project Hayes received resource consent, Dr Turner expressed concern that the high-voltage direct current (HVDC) link between the North and South Islands was being poorly managed.

By David Bruce

The Otago Daily Times

8 November 2007


URL to article:  https://www.wind-watch.org/news/2007/11/07/capacity-of-grid-in-doubt/