Ohakuri power plant
| Ohakuri Power Station | ||
|---|---|---|
 |
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| location | ||
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| Coordinates | 38 ° 24 '28 " S , 176 ° 5' 19" E | |
| country |
 New Zealand
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| place | Waikato region | |
| Waters | Waikato River | |
| power plant | ||
| owner | Mercury NZ Limited | |
| operator | Mercury NZ Limited | |
| Start of planning | 1949 | |
| construction time | 1956 to 1961 | |
| Start of operation | 1961 | |
| technology | ||
| Bottleneck performance | 112 megawatts | |
| Standard work capacity | 400 million kWh / year | |
| Turbines | Francis turbines 4 × 30 MW | |
| Generators | 4 × 28 MW | |
| Others | ||
| Website | www.mercury.co.nz | |
The power plant Ohakuri ( Ohakuri Power Station ) is a hydropower plant on the North Island of New Zealand .
Origin of name
In the Māori language, the name Ohakuri is composed of the guards “ oha ” for “souvenir” or “memory” and “ kuri ” for “dog” . The name could thus refer to a valuable coat made of dog fur.
geography
The Ohakuri Power Station is the second power plant in a chain of eight hydropower plants on the Waikato River . The power plant is located 30 km north of the city of Taupo and can be reached from the New Zealand State Highway 1, which runs a good 3 km to the west via Ohakuri Road .
history
In 1949, the then New Zealand government began planning the Ohakuri power plant north of Taupo . The project was approved in November 1955, and work on the dam began in 1956. In 1958 it was decided to add a fourth generator to the power plant originally planned for three generators. In January 1961, the reservoir, which was named Lake Ohakuri , was flooded and the power plant was finally put into operation. The generators were brought into operational readiness one after the other in January 1961, June 1961 and February 1962.
As of 2020, the power plant will be operated by the majority state-owned company Mercury NZ Limited , formerly Mighty River Power .
Barrier structure
The barrier structure consists of a gravity dam made of earth with flood relief on the eastern side and a concrete gravity dam on the western side. The 94.5 m long and 51.8 m high earth dam has a width of 335 m at its base and tapers up to the ridge to 9 m wide. The four pressure tunnels leading to the power plant each have a diameter of 5.5 m and a length of 82 m. The overflow is 10.7 m wide and 245 m long.
power plant
The Ohakuri Power Station has an installed capacity of 112 MW and an average annual electricity generation of around 400 GWh . The four generators driven by Francis turbines are designed for an output of 28 MW each.
The turbines have undergone from 2011 to April 2014 a fundamental overhaul and introduced new wheels from Toshiba installed. In addition, changes were made to the intake manifolds . Up until this point in time, the cavitation damage to the turbine runners had been repaired by welding every three to four years, but this led to a change in the blade profiles over time. The total cost was estimated at NZ $ 28 million prior to commencement of work .
Reservoir
With the completion of the barrier structure, the water of the Waikato River was dammed up to form Lake Ohakuri . The lake, which extends over an area of 12.6 to 12.9 km², has a usable volume of 18.8 million m³ of water for electricity generation with a variable storage target of 285.1 m to 287.53 m
See also
Individual evidence
- ↑ a b 03. Ohakuri - Overview . Mighty River Power , archived from the original on June 10, 2011 ; accessed on January 6, 2020 (English, original website no longer available).
- ↑ Topo maps . Land Information New Zealand , accessed January 6, 2020 .
- ↑ a b c 03. Ohakuri - Technical . Mighty River Power , archived from the original on June 10, 2011 ; accessed on January 6, 2020 (English, original website no longer available).
- ↑ Hydro Generation . Mercury NZ Limited , accessed January 6, 2020 .
- ↑ Glen Twining : Rehabilitation of Turbines at the Ohakuri Hydro Power Station . In: Hydro Review . Volume 22, Issue 4 , July 1, 2014 (English, online [accessed January 7, 2020]).
- ↑ Upgrade for Key Waikato Hydro Station. Mighty River Power, October 21, 2011; Archived from the original on June 30, 2015 ; accessed on May 19, 2019 (English, original website no longer available).
- ↑ STATEMENT OF EVIDENCE OF FRASER SCOTT WHINERAY. (PDF 2.3 MB) Waikato Regional Council, pp. 8-10, 19-20, 24 , archived from the original on January 26, 2015 ; accessed on June 26, 2015 (English, original website no longer available).
- ^ Waikato Lake Levels . Mercury NZ Limited , accessed January 4, 2020 .
