You do have a point, the price has probably changed. The $0.40/lb I quote was about 10 years ago. And while energy costs have increased, other factors are keeping the overall costs down. For instance, while the haul trucks and other movable equipment operate much like a locomotive with a diesel engine running a electrical generator, most of the processing equipment runs on electricity from the grid. In my area, there are at least 2 mines (probably more) that run this equipment from a hydroelectric dam in the area. This electricity runs the mills, SX/EW operations, crushing & conveying, etc which make up the bulk of the machinery at the mine. While $/kWh may have gone up over time, it is probably nowhere near the increase in diesel. Further, a typical copper mine produces more than just copper. There is one mine that produces a significant amount of molybdenum. While the production is nowhere near what it produces in copper, at $40/lb, it pretty much pays for all of the mining operations, and makes the copper production icing on the cake. Thirdly, the costs to process the ore keep dropping with new techniques. My boss laments (he was a mining engineer for one of these mines) that 30 years ago it took 35,000 people to accomplish what it takes 2,500 people to produce 25 times the copper. So even though costs do rise, I don't think it is as bad as you might think.