Green Party energy policy in 2017 election


Today the Green Party released their energy policy for the 2017 election.

The reaction from Business New Zealand has been largely positive. Other than the commitment to 100% renewable energy, the lobby group believes that it is constructive and comes about as a result of working with the party.

I support parts of the policy too. One area which is encouraging is the Green Party plan to support inter customer trading of electricity that private users generate and put back into the grid. Likewise encouraging the lines companies to amalgamate in places means that the management of the grid across New Zealand should hopefully become less fractured than 29 separate entities at work.

New Zealand is rich with options for renewable energy. It sits in the “Roaring Forties” belt of latitudinal westerly winds, which upon contact with the Southern Alps give rise to substantial rainfall enabling hydroelectric power generation, as well as significant opportunities for wind power. The reasonably high sunshine hours in towns like Blenheim, Whakatane and Nelson ensure the natural potential for solar power also exists. Around the coastal environment there are also several locations where tidal power can be potentially harnessed.

I am aware of significant investment in geothermal energy in New Zealand that has most likely utilized the available capacity. Geothermal systems are quite delicate in nature and thus a fine balance exists between re-injecting too much water back into the ground and not enough.

Another source of power that is heavily utilized is hydro power. Although it has lost a portion of the market as other sources have come online, hydroelectric power makes up about 60% of New Zealand’s total electricity supply. However it is dependent on reliable northwest rainfall feeding the Upper Waitaki Power Scheme, and the Clutha, Roxburgh and Manapouri power stations in Central Otago and Southland.

But there is undeveloped and under researched potential in New Zealand energy resources as well. One example is that New Zealand has a thriving waste stream of bio-waste ranging from waste cooking fat and oil, that at least on a small scale has been demonstrated to be suitable for refining. New Zealanders discharge a huge volume of green waste at refuse stations each week. On a local scale there are a few operations where the gas is captured and used to power onsite facilities. However these are few and far apart. Due to the uncertainty and a lack of interest by Government in biofuel, I support research into whether or not a nation wide bio-fuel programme can be developed in New Zealand.

There is one concern I do have though and that is that the Green Party might try to mothball with the intention of decommissioning thermal plants that rely on coal and oil, such as Huntly, Stratford and Whirinaki. These power stations would prove useful in maintaining energy supply during dry periods when the hydroelectric storage lakes are running low, or if there has been a problem with other sources.

Gisborne power outage shows need for back up lines


By the time you read this, hopefully power will have come back on in Gisborne, which is suffering through a black out that has affected the entire city of 40,000 people. Aside from having entirely tragic circumstances (see below)causing it, the complete black out of a New Zealand urban area raises questions about the reliability of the local power grid when placed under stress.

Except that this was not caused by a natural disaster. In fact  this was not caused by a disaster – although it was certainly disastrous for the families of the victims –  at all, but by a fatal plane crash that killed two men. It struck the 110kV link which has six lines. All were affected and outages reached as far north as Tolaga Bay.

I cannot recall a time prior to yesterday when an entire New Zealand urban area has gone dark because of one event/incident that was not an act of nature. On 22 February 2011, 80% of Christchurch lost power as a result of the seismic activity that day, but this is an exception rather than the norm. Some of the major power cuts in the last 25 years include:

  • In May 1991 a power cut affected Christchurch sending 2/3 of the city into darkness, affecting around 220,000 people, but this lasted only an hour.
  • In 1998 Auckland C.B.D. had black outs that cost millions of dollars in lost revenue for businesses and lasted five weeks before the last customer was reconnected
  • In 2006 a power cut in Auckland affected 700,000 people, or about 3/4 the total population of the city
  • In 2014 a power cut caused by line failure at Penrose Substation in Auckland lead to nearly 80,000 without power for several days

Much of the time these cuts have been traced back to substandard equipment at substations, or substandard maintenance of equipment at substations and switch yards. Following the 1998 and 2006 power outages in Auckland, pledges to improve reliability of supply were made. In accordance with these pledges additional switch yards were established and existing lines upgraded from 110,000kV to 220,000kV, thus doubling their capacity to carry power.

In the case of Gisborne’s power cut, an event such as a plane crash has shown how one incident can affect the entire distribution network of a particular link. Whilst the physical impact of the plane onto the infrastructure at the crash site could not realistically be controlled, how the network reacts to the accident could have been controlled better had there been an alternative link carrying the required power supply.