Here's another article predicting copper supply over the next several years.

Some "experts" suggesting we won't see increased demand until 2020. I have little faith in the ability of these advisors or institutions to make predictions. I'm also skeptical, as I often think they have a conflict of interest in that they're making predictions on sectors that they themselves invest in. A surplus of 150,000 tonnes can get eaten up pretty quickly. They're going to need about 25% of that number to meet the orders for the testa model 3 alone! I'm assuming they're going to get 500,000 orders with 150lb copper/car I'm guessing.

Then there's the possibility of increased construction, housing, cars, the possibility of turning to using copper again as collateral for borrowing. If the predictions of China's use changes by even 1%, it would change a surplus of that amount to a deficit. There are just too many unknowns. That being said, longer term, I think copper is one of the safest metals to be invested in, if you're looking at commodities.

http://investingnews.com/daily/resource-investing/base-metals-investing/copper-investing/thomson-reuters-gfms-copper-market-survey/?mqsc=E3831836&utm_source=WhatCountsEmail&utm_medium=INN_FullList+INN%20Daily+INN%20Daily&utm_campaign=INN%20Daily%20Automated