Welcome to Geothermal Power

Welcome to the Wairakei Geothermal field trip for Term 1, operating from 1-3 March 2006. As well as this site there are other LEARNZ field trips on this topic. We suggest you use the Field Trip Chooser on the LEARNZ home page to find similar field trips. Then enrol your class at no extra cost.


. Image: Heurisko Ltd, click to enlarge.
The Western Borefield currently provides 50% of the steam used to generate Wairakei's electricity. Image: Heurisko Ltd.

The Wairakei Power Station is owned and operated by Contact Energy Limited, who produce 25% of NZ's electricity. The Station is an important national generator of electricity. The Crown owns the geothermal resource itself.

The power station is situated 7km North of Taupo township, and is of particular interest because it

  • it was the first geothermal plant in the world to use very hot water as the source of steam that is used to drive the turbines
  • it produces 1550 GWH of electricity per annum, which is enough to supply Taupo, Rotorua, Napier and Hamilton
  • it produces 4.3% of NZ's electricity production
  • it is an important 'base load' station
  • it has run at better than 90% of maximum output since the 1960's
  • its efficiency of converting heat energy to electrical energy is 37%, which is comparable to newer geothermal plants around the world. Some of this efficiency is due to the use of the very cold Waikato River water in the condensers.
Area of steam field 25 sq km
Production wells 54
Reinjection wells 9
Monitor or unused wells 70
Average depth of wells 600 m


Field Trip Plan

Tu 28 Feb Travel Day. Join Donald as he sets the scene - read Donald's Diary as he flies north from Christchurch to Rotorua and drives across to Taupo.
We 1 Mar Visit a geothermal drill rig as it searches for hot water then find out what bores, well heads, separators, flash plants, silencers, and pipelines do. Listen to the first 2 audioconference recordings. Read Donald's Diary for Wednesday. Watch the 9 videos. View the panorama of the drill rig at Wairakei 248 bore hole.
Th 2 Mar Go inside the power station to see the different sets of turbines, condensers and generators that make Wairakei so efficient. Listen to today's audioconference recording. Read Donald's Diary for Thursday. Watch the 17 new videos. View the panorama of Wairakei Geothermal Power Station.
Fr 3 Mar Visit the high voltage switchyard and the Wairakei Control Room to see what factors must juggled to provide a stable power supply. Listen to today's audioconference recording. Read Donald's Diary for Friday. Watch the 6 new videos. View the panorama of Wairakei's Pink silica terraces.

What's New

Tu 21 Mar See who won the Polycom SoundStation in the competition.
Tu 28 Feb All of the audioconference questions are up, ready for printing. During the field trip, look for What's New in the table immediately above labelled Field Trip Plan.
Fri 24 Feb Schools have responded to the newsletters and booked in to ask questions in the audioconferences. Meet the experts who will guide you on this field trip.
Wed 1 Feb This Wairakei Geothermal site goes live.

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