Meridian spokesperson Claire Shaw said the overhaul of the generating unit took four months, and the project remains on track to complete all six units by January next year.

The overhaul involved taking delivery of a new turbine runner from Japan with other generating equipment coming from France.

The dismantling, mechanical overhaul and reassembly and was undertaken by Transfield Services with support from local companies and Meridian’s own engineering and operational staff.

Benmore is the country’s second-largest hydro station and has been delivering electricity to New Zealand since 1965. This project has been developed to ensure that Benmore continues to operate reliably and more efficiently for the next 40 years.

The five-year upgrade project began in January 2006.