The Tuai Power Station was commissioned in 1929 as part of the Waikaremoana Power Scheme, located between Te Urewera National Park and Wairoa, along the upper 7km of the Waikaretaheke River and operates today along with two other power stations – Kaitawa and Piripaua. Water is taken from Lake Waikaremoana via tunnels to Kaitawa Power Station, before being discharged into Lake Kaitawa, passing through Tuai Power Station and discharged into Lake Whakamarino. From there, water is carried by tunnel to Piripaua Power Station and is discharged into the Waikaretaheke River.
The professional team at Argus Fire Protection services have been contracted to upgrade the fire extinguishing systems at the Tuai Power Station which is located at the village of Tuai, approximately 50 km north of the township of Wairoa off SH 38 on the edge of the Urewera National Park. Kaitawa and Piripaua Power Stations are also located adjacent to SH 38 in close proximity to Tuai Power Station which is the management, maintenance and operations centre for the three power stations in this area. The 20MW generators on this site are a horizontal shaft driven Francis turbine unit, with steel casing and no additional outer enclosure.
Until recently, when Argus Power was involved in the upgrade of the fire protection services there, the Tuai generators (G1, G2 & G3) had no form of fire extinguisher nz system. The age and condition of the generators has put them at a high risk of a generator fire, and of the three generators G3 is most at risk. Genesis Energy have approved the project to have systems fitted that meet the operational needs of the business and industry best practice requirements for Generator Fire Protection Systems.
This project required the design and installation of a fire extinguishing system complete with an aspirating smoke detection system to protect the three generators at Tuai Power Station. The generators each have an independent detection system with networked aspirating detection units and control equipment.
The extinguishing system proposed and installed is a hybrid type system, comprising of suppression through reducing the oxygen % in the with fine mist at 10 microns with the combination of low pressure water and nitrogen that gives an additional feature of cooling that is an advantage to other means of gas suppression. The system has been designed with flexibility to enable maintenance works to be conducted onsite while also providing a system that will outlast its installers with stainless steel pipework, fittings and fastenings.