PacifiCorp, which does business as Rocky Mountain Power in eastern Idaho, plans to meet customer demand over the next 10 years through increased reliance on energy-efficiency measures, natural-gas plants, market purchases and renewable resource additions.
The Idaho Public Utilities Commission (PUC) is taking comment through July 11 on PacifiCorp's Integrated Resource Plan (IRP). The PUC requires regulated electric and gas companies to file the plan every two years.
PacifiCorp says it expects to need a significant amount of new resources to offset load growth of about 1.8% a year and 2% growth during peak-use periods in its six-state territory. The most rapid growth is occurring on the east side of its territory, which includes about 1 million customers in Utah, Wyoming and Idaho.
The utility also needs to replace power generated by the expiration of a number of long-term purchase power agreements. Without new resources, PacifiCorp anticipates a capacity deficit of 326 MW this year and 3,852 MW by 2020.
Currently, PacifiCorp's energy mix, which looks at the sources of generation over a year's time, includes 62.5% from coal plants. The proposed IRP reduces coal generation to 36.3% in 2020. However, natural-gas generation would increase from the current 11.7% to 25.5% in a decade, as would generation from renewable resources – including 800 MW from wind power – from 7.4% to 10.7%.