It takes a significant amount of energy to extract and produce the copper and other minerals we produce, and we are committed to using and seeking additional ways to improve our energy efficiency.
At Kennecott, we are committed to researching and implementing additional ways of increasing on-site generated power supply and energy efficiency throughout our operations. Our $10 million, 6.2 megawatt (MW) combined heat and power (CHP) system at our refinery is an excellent example of this commitment. The CHP system is more than 80 percent energy efficient compared to separate heat and power systems, which are estimated to be less than 50 percent efficient. The 6.2 MW CHP system produces enough electricity to power 6,000 average-sized homes.
CHP, also known as cogeneration, is an efficient, clean and reliable approach to generating power and thermal energy from a single fuel source. The refinery CHP system meets the steam requirements of the refinery and provides up to 50 percent of the electrical needs of the plant.
Key benefits of our CHP system:
- Produces up to 6.2 MW per hour — equivalent to the electrical needs of 6,000 average-size homes
- Produces up to 70,000 pounds of steam per hour
- Provides distributed onsite steam and power production for use in the copper refining process
- Improves power generating efficiency to above 80 percent, compared to about 50 percent for traditional power plants
- Diversifies our energy generation portfolio and improves power reliability
In May 2019 after 75 years of operation, we retired the Utah Power Plant located in Magna, Utah. Following regulatory approval, we will pair 1.5 million megawatt hours of electricity with Green-e Energy certified carbon-free renewable energy certificates, primarily from Rocky Mountain Power’s growing portfolio of wind and solar resources.
The plant retirement and acquisition of renewable energy certificates will remove more than 1 million tons of CO2 from Kennecott’s operations and reduce its annual carbon footprint by as much as 65 percent. By retiring four coal-fired boilers since 2016, we will eliminate 6,000 tons of PM 2.5 and precursors annually from our airshed. This is an important milestone in achieving Rio Tinto’s goal of being carbon neutral by 2050.