A bigger question remains as to whether this project can be repeated on a bigger scale for all of Butte, using the mine waters from the many copper-mine shafts.

“There’s a lot of discussion about that because of the immensity of the water (resource),” Blackketter said. “The answer is that’s why we did it. We did it to see if it was economically viable to use that water in the mine shaft to heat and cool a building.”

The verdict?

“The answer is yes,” he said. “You absolutely know it will work. The water in the Berkeley Pit, you wouldn’t have to drop the water temperature much to heat the whole city of Butte.”

But?

“(It’s like) wind, solar,” he said. “How much energy do you have to put in to build the apparatus versus how much can you get out of it? Those economics all come into play. Can you do it? Yes. Should you do it? That’s another question. That’s the big question.”

Even before such research is done, Blackketter foresees several barriers to heating Butte with geothermal energy from the mine waters.