LIE BACK AND THINK OF NEW ZEALAND

by Philip Temple

Two of the arguments used by Meridian Energy to support its gigantic Project Hayes wind factory project are that it is ‘in the national interest’ and necessary to meet the growth of power demand in the south. In winter, we are told, power has to be flashed south over the Cook Strait cable because South Island hydro power supply is inadequate. Wind factories are, therefore, essential if we are to keep southern lights and heaters burning.  

Discreetly kept off the agenda is an examination of just how much power Otago produces already, how much Otago uses and where that southbound North Island power actually goes to. You do not need to be an energy expert to work it out.  

Otago hydro dams have the capacity to generate up to 1730 MW of power. This includes the Clutha dams, Clyde and Roxburgh; Waitaki, Aviemore and Benmore on the Waitaki and smaller schemes such as Waipori.  

But how much does Otago actually use?  Just go to http://www.systemoperator.co.nz/?id=5970  and you can find out which regions are sucking up the power.  There are 14 Grid Zones listed and, at any time of the day or night, you will see that Otago consumes significantly less than any other region in New Zealand, except for Westland with its tiny population. 

Canterbury consumes six times as much power as Otago.  Southland - even excluding the gross  consumption of power by the Tiwai Point smelter - manages to use about twice as much.  Not only does Otago export 70% of its average power generation to Canterbury and Southland, none of the North Island export in winter goes further south than Christchurch.  So when Meridian Energy talks of Project Hayes providing enough power to supply about 263,000 average households - to make us feel all warm and comfy - they really mean Christchurch households.  Or, more realistically, Canterbury dairy farms and factories.  

Yet Meridian’s figures are extremely optimistic - based on Project Hayes generating power at a much higher rate than other wind farms.  And not taking into account up to 25% loss of power in its transmission north.  To transmit Project Hayes power, Meridian admits that a $40 million upgrade ( at least) of the transmission system would be needed. The cost of generating this power is rising to the point that even Meridian now hedges its bets by saying Project Hayes will only go ahead if they deem it to be ‘economically viable.’  That is, if they can persuade customers to pay a high enough price.  And amongst the complex web of consumers and power companies, Comalco sits as the big black spider, demanding to be fed continuously at a fixed rock bottom price that, at the other end of the pricing chain, is subsidised by everyone else.

If Canterbury needs six, even seven, times as much power as Otago, why are wind farms not being constructed there? Canterbury has plenty of wind flow, as any examination  of NIWA data maps show. In particular, in the coastal zone between Ashburton and Banks Peninsula. As anyone who has lived in Christchurch, North Canterbury or on Banks Peninsula also knows, the nor’easter is common and persistent to the point of aggravation.  MainPower recognises this in its application to build a moderate size wind farm on the Mount Cass hills near Waipara. 

Wind power is clean and useful in a global-warming world. But overseas experience already shows that it can turn out to be an inefficient and uneconomic solution to energy needs.  The Commissioner for the Environment, Morgan Williams, has recommended that New Zealand should follow Danish practice, the most successful approach to wind power planning and use for a small country. This provides for small scale wind farms to be built close to where the power is needed and with the buy-in of local communities regarding siting, operation and investment. A recent survey suggested that 87% of New Zealanders liked the look of wind farms. So there should not be too much objection to them being placed close to towns and cities!