Aniwhenua Hydro Station

The environmental award-winning Aniwhenua Hydro Station utilises a renewable energy source.

The Aniwhenua station is located on the Rangitaiki River and is owned and operated by Todd Energy retail and generation company, Bay of Plenty Energy (BoPE). Based in the heart of the Bay of Plenty, the plant provides a significant amount of the region's electricity needs.

Aniwhenua Hydro Scheme was constructed in the late 1970's and is named after the falls that are adjacent to the powerhouse. The scheme involved the damming of the Rangitaiki River above the falls, forming a 255 hectare storage lake. Due to its embedded nature close to the customer base it services transmission loses are minimised.

Lake Aniwhenua is also a major recreational asset providing superb fishing, duck shooting, water skiing, camping and picnicking for thousands of locals and visitors each year.

Lake Aniwhenua is also on an important eel fishery of particular significance to Maori. An ongoing programme transfers migrating elvers and eels both upstream and downstream from the lake, successfully maintaining eel stocks.

Generating Plant

The Aniwhenua scheme consists of a 200 metre long, 10 metre high dam structure with five spill gates comprising of two radial gates and three flap gates which can discharge 1,270 cubic metres of water per second.  Compensation water is released from the dam to preserve the original river channel and maintain flow over the Aniwhenua falls. A small turbine coupled to a generator is driven by the compensation flow to supply power to the local Bay of Plenty network.

A 2.2 kilometre canal diverts water from the lake to a headpond above the powerhouse.

Water flows from the headpond through two 3.4m diameter steel penstocks at a rate of 75 cubic metres per second to the powerhouse 38 metres below. This flow drives two 12.5 MW generators before being discharged back to the river just below the Aniwhenua Falls.

Operation of the Aniwhenua station is completely automatic - run from a sophisticated computer system at BoPE's Whakatane office.