When Idaho Power was founded in 1916, the company had a total system generation capacity of 22.3 megawatts (MW) and a customer count of 17,789. Today, the company’s nameplate generating capacity is 3,084 MW, and its customer count is more than 473,000. Just like the speedometer on your vehicle shows 120 mph, nameplate capacity refers to the dam's power plant and its maximum ability to generate electricity under ideal conditions.

The company built most of its hydro facilities during the 1940s, 50s and 60s, culminating with construction of the three-dam Hells Canyon Complex in 1968. Through this time, all of Idaho Power’s electricity was generated at its hydroelectric plants.

Hydroelectric resources now account for about half of the company’s generating capacity. This low-cost, emission-free source of energy has helped ensure Idaho Power’s electricity rates are consistently among the lowest in the nation.