Highlights

The $31 million project is Rio Tinto's first wind generation facility and the first large-scale wind farm in Canada's Northwest Territories

In 2015, the mine’s four turbine 9.2 megawatt wind farm exceeded annual targets

Diesel fuel offset was 5.2 million litres and CO2-e offset was 14,404 tonnes

Wind farm facts

Technical

  • Four Enercon E70 generators
  • Gearless direct-drive design operating to -40°C
  • Total installed and demonstrated capacity: 9.2MW
  • 7 year estimated payback

Dimensions

  • Tower hub height: 64m
  • Turbine rotor diameter: 71m
  • Total turbine height: 100m

In 2015, the mine’s four turbine 9.2 megawatt wind farm exceeded annual targets. For the year, diesel fuel offset was 5.2 million litres and CO2-e offset was 14,404 tonnes. Over the year, the facility generated 20.8 gigawatt hours with an operational availability rating of 98 per cent. Renewable energy provided 11 per cent of the mine’s power needs.

Peak power levels, achieved for brief periods, have surpassed 50 per cent – enough wind energy to power Diavik’s underground mine.

The $31 million project is Rio Tinto's first wind generation facility and the first large-scale wind farm in Canada's Northwest Territories. With the wind farm, brought on-line in September 2012, Diavik became the operator of the world's largest wind-diesel hybrid power facility. The off-grid Diavik Diamond Mine is located on an island in a subarctic lake called Lac de Gras, in Canada's remote Northwest Territories.

In 2015, the wind farm reduced the mine's annual diesel fuel requirement by 5.2 million litres and provided 11 per cent of the mine's power needs. As well, it will reduce Diavik's seasonal winter road fuel haul by approximately 100 loads. The extreme location of the mine meant a highly innovative design was needed for the turbines, in order to maximise their output in the harsh subarctic climate. With temperatures in the winter as low as 
-40°C, the blades are all fitted with de-icing technology, and represent a new benchmark for wind power in low temperatures.

The project received capital approval in 2011 and in 2012, all the wind farm components were transported over the winter road - 60 loads were needed including the 33-metre epoxy resin blades (6.5 tonnes each) which were the longest loads ever hauled over the road. Every detail was covered - even customised trailers were required to ensure the turbine components could successfully navigate the winter road's 65 portages.

A key part of the early work was Diavik's renewable energy feasibility study which began in 2007 with the installation of a meteorological tower to collect weather data at the minesite. The three-year study, confirmed Diavik had a strong wind resource.

11%

of the mine’s power needs were provided by renewable energy

In 2011, with the study complete, Diavik donated the tower to a local Aboriginal partnership studying the wind resource potential at the old Giant Mine. Located in Yellowknife, Northwest Territories, the Giant gold mine shut down in the 1990s and has long-term environmental challenges. Project partners on this initiative hope that the meteorological tower will demonstrate a viable wind resource and one day lead to a renewable energy source to assist with reclamation of the Giant minesite.

As with the weather tower, Diavik is optimistic that the experience and knowledge gained through the planning, development, construction, and operation of its wind farm will be able to be shared so that other projects can be developed in the future.