Contact Energy has started a $30 million turbine upgrade at the Roxburgh hydroelectric dam to improve the dam’s efficiency and increase average annual generation by 44 gigawatt hours (GWh).

The project will replace four of the eight turbines, with the first shipment of new components arriving at the dam last week.

The new 28.5 tonne, 3.9m diameter stainless steel turbines were designed by the German manufacturer Voith Hydro, a supplier of hydroelectric equipment, technology and services.

Contact Energy acting head of projects and performance Kirk Pritchard said the new turbines were more efficient, resulting in additional energy output for the same amount of water.

“The increase in the station’s electricity generation is enough to power an extra 6000 homes.”

A new turbine travelling over the Beaumont Bridge to Roxburgh dam. PHOTO: Supplied 

Roxburgh power station was commissioned between 1956 and 1962 and still generates with the eight original Canadian built turbines.

The first four were installed between 1956 and 1957 and the second four between 1960 and 1961.

“For 70 years in service, our existing turbines are still in a good, safe and usable condition, but they are inefficient by today’s standards and ready to retire before wear and tear requires too much maintenance and increases the risk of failure,” Kirk said.

One of the original turbines being unloaded from the ship during station construction. PHOTO: Supplied

Roxburgh dam. PHOTO: Supplied 

Voith Hydro has subcontracted New Zealand based energy solutions provider MB Century to undertake the installation works who, together with Voith Hydro’s on-site technical experts, will install the four turbines back-to-back over a two-year period.

In a media release Contact said the spend on the new turbines is part of their commitment to lead the decarbonisation of the country. 

“The update to Roxburgh will enable us to deliver more renewable energy and displace almost 20,000 tonnes of carbon dioxide emissions a year,” Kirk said.

 “As with any major upgrade to a power station, teams of contractors from around Aotearoa – and sometimes further afield - are needed to help with the work. 

“This will be a great boost to the local economy with local contractors assisting on some activities, along with more workers from outside the region staying in accommodation and eating out over the next two years.”