Wednesday. The Wairakei 248 bore hole is to to drilled by this 500 tonne drill rig. It stands about 45m high and will drill a 3km long hole off centre using a'directional drilling' technique. It costs 45 000 dollars a day to run the rig and about the same for catering, accommodation, power, transport etc. It requires 50 big truckloads to move it all To transport it from Australia cost 2 million dollarsalone. To drill each geothermal well costs 2 to 3 million dollars. The 4 holes it will drill from here, should take 48 days. The crew will eat, sleep and work on site for two weeks then have two weeks off. They work 12 hour shifts. The drilling never stops. Effectively this site is a small mobile town. Image: Heurisko Ltd.

Thursday. The Wairakei power station, looking east. This is only a small section of the large Wairakei geothermal field near the Waikato River, which flows (R to L) immediately behind the tallest buildings. On the left is the nationally important 220KV switchyard then Station B and Station A nearer the centre. The offices and control room are in the front, centre. Image: Heurisko Ltd.

Friday. The dramatic Wairakei Terraces, next to SH1 at Wairakei. The terraces are formed by silica being deposited by 'waste' geothermal water that flows from a geyser at the top, centre. As the water temperature drops below 87 degrees silica is deposited. The silica deposited over this landscaped terrain produces a dramatic and impressive feature but also illustrates a major problem in the use of geothermal water, namely that water must be kept above 89 degrees to avoid deposition where it is not wanted (eg machinery, pipes and in reinjection wells).These terraces are only 2 years old and will continue to improve in appearance, however the same deposition in a $2 000 000, 3km deep well can block it within 2 days. Image: Heurisko Ltd.

The turbine of Generator G9 during an overhaul. The turbine shaft and blades have been removed by removing the top half of the turbine casing. The generator is still in place in the green housing. The steam control system is on the left - Image: Heurisko Ltd.

The turbine shaft of a Mixed Pressure Turbine sits in a giant lathe while being rebladed . Note the 7 stages of blading on the left and 8 on the right - Image: Heurisko Ltd.

The western borefield supplies about 50% of Wairakei's steam. It consists of about 30 wells drilled to a depth of about 600m - Image: Heurisko Ltd.

The outdoor switchyard at Wairakei uses air as the insulator between circuits and therefore must cover a large area. The two Power Station buildings can be seen behind to the right. Station A is the blue building and Station B is the grey building to the left of it - Image: Heurisko Ltd.

A vertical panorama of Mixed Pressure Steam Turbine 11 (Grey and Red), Generator 11 (marked G11) and its Condenser beneath (Green). River water enters through the large green pipes in the center - Image: Heurisko Ltd.

The upper level of Station A houses the 4 low pressure turbines numbered G7 to G10. The steam turbine of Generator 10 is being reassembled after maintenance. The turbine shaft is visible in the middle right and its cover is slung beneath the crane in the upper distance. Twenty minutes later it was in place. The lower part of the image looks down on the condenser which is painted green. The white line around the turbine shaft is a sealant - Image: Heurisko Ltd.

Inside Station B of the Wairakei Power Station showing a Mixed Pressure steam turbine. The steam turbine is grey and red with two steam control valves infront of it. The generator is light green and its exciter is smaller and to the far right. The most striking feature is the bright green and massive condenser beneath the turbine. It is this condenser that makes such turbines economic, efficent and workable. Waikato River water enters the condenser through the two central pipes and is sprayed into the steam to cool it, creating a vacuum that pulls the low pressure steam through the turbine - Image: Heurisko Ltd.

Brian Ultee at work inside the Control Room of Station B at Wairakei Power Station. This room still contains the original meters and control equipment giving information about turbines, generators and electrical output to the national grid. It has been replaced by a much smaller, computer based system in the administartion building, that controls all of Wairakei, Poihipi and Ohaaki power stations with the click of a mouse - Image: Heurisko Ltd.