The 2011 hydro season began earlier and lasted significantly longer than in recent years, stretching well into the summer months.
This extra low-cost energy contributed to an average 18% decline in wholesale electricity prices compared with prices in 2010 at Mid-Columbia, a major Northwest wholesale pricing hub near the Washington-Oregon border.
Hydroelectric generation in the Pacific Northwest is typically highest in the late winter and spring, when river flows are high because of snowpack melt.
