Dam nameplate not true output

Regarding the March 12, 2025 story in the Hungry Horse News about Mick Ruis’ plans for CFAC land and the possibility of huge cryptocurrency server farms, the public should know there is a difference between total nameplate generating capacity of a hydroelectric dam and expected average output.

On Feb. 24, 1956, shortly after the Hungry Horse Dam was completed, the government ran a test, opening up the spigots and letting the generators run at beyond nameplate capacity ­— 325 megawatts. The reservoir was severely drawn down within a month or two, just as Hungry Horse News editor Mel Ruder warned in 1953. The generators were rewired decades later, boosting their nameplate capacity to more than 400 megawatts, but local rainfall and the reservoir’s geography can’t be changed. 

In other words, the reservoir acts like a battery and can get drawn down quickly. In reality, the Hungry Horse Dam averages around 60 megawatts in electrical output, depending on drought conditions, which was enough for two potlines in 1953, when the first four pot rooms were built at the aluminum plant. Expanding the smelter to five potlines and 10 rooms required 300 megawatts. 

The extra power came from the BPA’s Hot Springs line to the Noxon Dam and a line from the Libby Dam -- you can count the three main transmission lines running to the CFAC site as you drive around Flathead County.

Richard Hanners

John Day, Oregon