Mining uses much more electricity than most other heavy industries, so it makes sense to move that high energy use to off-peak hours, because that evens out the demand on the grid, making it possible to squeeze more power out of fewer dirty electric plants, and to use more clean energy.
So the Ontario government has just asked the nickel-mining giant XStrada, and the second-largest mining company in the world, Vale; to work nights.
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Under the new pricing structure, the two giant mining operations stand to reduce their giant electricity bills, as much as 15%. An Xstrata representative said equipment and operations that use a lot of power such as the skips used to haul ore out of their mines could be operated at off-peak periods instead of during the day, according to local news outlet Northern Life.
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And mining is not the only heavy industry that is being prodded by the Ontario government to working the night-shift with these new incentive rates. All told, about 200 of the province’s heaviest electricity users will be affected by the new rate structure pushing them to work nights.
http://cleantechnica.com/2010/09/26/mining-by-moonlight-to-save-energy/