The Idaho legislature is totally dominated by farmers (I mean this literally: The Idaho congressmen are primarily farmers.). These farmers are allowed way better deals on hooking up solar and providing it to the grid than city consumers. In addition, a large number of farmers already have solar panels since grid hookups are very expensive.
The "California arbitrage" has been very profitable for Idaho for many years: This involves selling California renewable hydro, for which they pay a premium, and buying coal from Utah to replace it. (Ever driven north of SLC to Idaho on I-15? Those high voltage transmission lines are there for a reason.)
If I had to bet, I would suspect the lines from the Nevada coal plant also supply California, and Idaho Power will sell the solar production there.
The "California arbitrage" has been very profitable for Idaho for many years: This involves selling California renewable hydro, for which they pay a premium, and buying coal from Utah to replace it. (Ever driven north of SLC to Idaho on I-15? Those high voltage transmission lines are there for a reason.)
If I had to bet, I would suspect the lines from the Nevada coal plant also supply California, and Idaho Power will sell the solar production there.