Maraetai Power Plant
| Maraetai I / II Power Station | ||
|---|---|---|
| location | ||
|
||
| Coordinates | 38 ° 21 '7 " S , 175 ° 44' 38" O | |
| country |
 New Zealand
|
|
| place | Waikato region | |
| Waters | Waikato River | |
| power plant | ||
| owner | Mercury NZ Limited | |
| operator | Mercury NZ Limited | |
| construction time | 1946 - 1952 Maraetai I 1959 - 1970 Maraetai II |
|
| Start of operation | 1952 Maraetai I 1970 Maraetai II |
|
| technology | ||
| Bottleneck performance | 360 megawatts | |
| Standard work capacity | 855 million kWh / year | |
| Turbines |
Francis turbines 10 × 37.29 MW |
|
| Generators | 10 × 36 MW | |
| Others | ||
| Website | www.mercury.co.nz | |
The power plants Maraetai I / II ( Maraetai I / II Power Stations ) are two 400 m away from each other, driven in the same reservoir hydroelectric power plants on the North Island of New Zealand .
Origin of name
In the Māori language, the name “ Maraetai ” is composed of the words “ marae ” for “open area” or “courtyard” in front of a wharenui (meeting house) and “ tai ” for the “sea” or “coast” . Therefore the name probably comes from some coast. As an example, there is a Maraetai southeast of Auckland at Waitemata Harbor .
geography
The two Maraetai Power Stations are combined to be the fifth power plant in a chain of eight hydropower plants on the Waikato River . The power plants are located around 17 km southwest of the city of Tokoroa and can be reached from the south-east from the New Zealand State Highway 32 , which runs 5 km to the south-east, via Whakamaru Road and Waipapa Road .
history
After a five-year planning and preparation period, work on the dam began in 1946, but the planned completion in 1951 could not be realized due to a lack of material, a shortage of workers and difficulties in the construction industry. When the first power station building was completed in 1952, the first three of five planned generators were connected to the power grid in October and November. The other two generators followed in January and April 1954.
The construction of the second power station building began in 1959, but was postponed in 1961 in favor of the project to connect the power grid via Cook Strait and was not completed until 1970. The first two generators were put into operation in July 1970, the third followed in September and the last two in November 1970 and February 1971.
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 riverbed of the Waikato River was dammed up to Lake Maraetai by means of an arch dam , which extends with a height of 87 m over a length of 133 m through the valley . The base of the dam is 15.2 m wide and the crown is 11 m wide. The second barrier structure is less complex, as the water from the reservoir is led to the power plant via a 12 m wide and 12 m deep canal, which runs parallel to the river bed for a length of 550 m. The dam here is only 60 m wide. To both power plants lead five pressure tunnel with subsequent pressure pipes , which in Maraetai m I in a length of 70 in a diameter of 4.8 m are formed and to the power plant Maraetai II m with 4.6 diameter over a length of 102 m extend.
power plant
Even if the Maraetai Power Station has two power plant halls , the operator regards the two systems as one power plant. The total installed capacity of the plant is 360 MW and comes to an average annual electricity generation of around 855 GWh . The ten generators driven by Francis turbines are designed for an output of 36 MW each.
Reservoir
With the completion of the barrier structure, the water of the Waikato River was dammed up to form Lake Maraetai . The lake, which extends over an area of 4.1 km², has a volume of 6.7 million m³ of water that can be used for power generation with a variable storage target of 184.98 m to 189.47 m.
See also
Individual evidence
- ↑ a b c 06. Maraetai - Overview . Mighty River Power , archived from the original on July 20, 2011 ; accessed on January 8, 2020 (English, original website no longer available).
- ↑ Topo maps . Land Information New Zealand , accessed January 8, 2020 .
- ↑ Lake Maraetai . In: NZ Topo Map . Gavin Harriss , accessed February 8, 2020 .
- ↑ a b c d e 06. Maraetai - Technical . Mighty River Power , archived from the original on July 20, 2011 ; accessed on January 8, 2020 (English, original website no longer available).
- ↑ Hydro Generation . Mercury NZ Limited , accessed January 8, 2020 .
- ↑ STATEMENT OF EVIDENCE OF FRASER SCOTT WHINERAY. (PDF 2.3 MB) Waikato Regional Council, p. 19 , archived from the original on January 26, 2015 ; accessed on January 6, 2020 (English, original website no longer available).
- ^ Waikato Lake Levels . Mercury NZ Limited , accessed January 4, 2020 .
