By 2030, only two of Rocky Mountain Power’s 11 Wyoming coal-burning units will remain in operation, according to an Integrated Resource Plan (IRP) filing on Friday.
Rocky Mountain Power also plans to convert a handful of others to run on natural gas — and keep those gas units open until some combination of renewables, storage, and advanced nuclear becomes established enough to take their place, according to the Casper Star Tribune.
The IRP calls for the retirement of 3,500 megawatts (MW) of coal-fired generation. It also includes 1,959 MW of new wind resources, 905 MW of upgraded or “repowered” wind resources, and 1,040 MW of new solar generation through 2036.
Rocky Mountain plans to use a new 140-mile, 500-kilovolt transmission line in Wyoming to distribute the energy from the new wind facilities and to relieve congestion on the company’s transmission system, according to the Daily Energy Insider.
The utility has opted to preserve coal use at one Glenrock unit for an extra 12 years, but it has also decided to ditch coal entirely at its Rock Springs plant — the largest of its kind in Wyoming – seven years ahead of schedule.
Rocky Mountain Power’s parent company, PacifiCorp, currently has about 5,000 megawatts of wind and solar in operation across its six-state service territory. Over the next decade, it wants to come close to quadrupling that number, while adding more than 7,000 megawatts of energy storage to help balance out renewables’ intermittent power output.
Pacific Power and Rocky Mountain Power combined serves over 1.6 million residential customers, 202,000 commercial customers, and 37,000 industrial and irrigation customers – for a total of approximately 1,813,000 customers. The service area is 143,000 square miles (370,000 square kilometers).
Pacific Power serves customers in Washington, Oregon, and California. Rocky Mountain Power serves customers in Idaho, Utah, and Wyoming.
