Wairua Hydro Station
The Wairua power station owned by Northpower was first built in the early 1900’s with this first of the generators installed in 1916. With great care and maintenance these are still operating. The water canal intake was upgraded in 2009 which has since provided a much improved water flow to the station. The new weir flap gates have also given better water management of the river in flood situations and a much reduced maintenance cost for many years. The power station’s aging control system has also been replaced to maximise output and reduce outages.
A 4th generator was installed at the site in 2007 and with the latest improvements to the canal walls, control systems and increased capacity (5MW or 50,000 100 watt light bulbs) the power station can now run at its optimum level. This work has also resulted in a station that is now a solid robust structure and the life of the asset has also been extended well into the future.
Northpower Network Power Usage
The maximum half hourly system demand on Northpower’s network is approximately 147 MW drawing supply from Transpower’s national grid at five main substations:
Maungatapere - 45 MW
Bream Bay - 45 MW
Dargaville - 12 MW
Maungaturoto - 18 MW
Kensington - 65 MW
Northpower Whangarei Depot Standby Generator
The Whangarei Depot recently upgraded its emergency standby generator. The increased demand in the essential supply system has arisen from Northpower’s requirement to improve storm and emergency control of the network distribution system and handle increased numbers of simultaneous callers requiring assistance. This means that during periods of severe weather, Northpower can respond more quickly to customer outages and get the power back on faster.