HPP Karapiro, New Zealand
Contract for major refurbishment
In January 2019, ANDRITZ Hydro signed a contract for the major refurbishment of the Karapiro hydropower station in New Zealand. The power station, which is owned by Mercury, is the last on the Waikato River, near Cambridge in the North Island.
The dam and powerhouse were originally constructed between 1940 and 1947 and contain three vertical Kaplan turbines originally supplied by Boving and subsequently rebladed by Tampella in the early 1980s, both companies predecessors of today’s ANDRITZ Hydro.
The main objectives of the refurbishment are to improve reliability, modernize the equipment and improve efficiency as well as power output. The scope of work includes the engineering supply, dismantling and installation of a completely new generator, including stator, rotor, bearing, thrust bracket and shaft system and replacement of the majority of the turbine parts that are not embedded for all three units. The new design will feature the first water lubricated Kaplan hub to be supplied in New Zealand, along with two more of the successfully implemented water lubricated turbine bearings. The discharge ring will also be completely replaced on all units.
The design phase has already started, with the first deliveries expected in early 2021 to allow assembly of the first stator on the power station loading bay. The entire installation is scheduled to be completed and commissioned by April, 2024.
This order follows two successful major projects with Mercury at the upstream power stations at Whakamaru and Aratiatia.