Primary copper production is a major activity in the mining sector of several countries. However, it is highly energy-intensive and poses important environmental hazards. In the case of Chile, the world's largest copper producer (40% of world total), we examine its energy consumption and energy-related environmental implications over a time horizon of 25 years. Concerning the latter, we focus on greenhouse-gas (GHG) emissions, one of the most debated environmental issues. This paper follows-up our previous report in which the current situation was analyzed and a particular technical option for improving the energy efficiency and concurrently reducing GHG emissions was discussed. Estimated reference or base (BS) and mitigation (MS) scenarios are developed for the period ending in 2020. The former assesses the energy demand projected in accordance with production forecasts and specific energy consumption patterns (assuming that energy efficiency measures are adopted 'spontaneously') with their resultant GHG emissions, while the latter assumes induced actions intended to reduce emissions by adopting an aggressive policy of efficient energy use. For the year 2020, the main results are: (i) BS, 1214 t of CO2/ton of refined copper content (49% lower than in 1994); (ii) MS, 1037 t of CO2/ton of refined copper content (56% lower than in 1994). CO2 emissions have been estimated considering both fuel and electricity process requirements. (D