Genscape said the amount of electricity generated from renewable energy resources for August was 1,174 gigawatt hours, the lowest level since October and 4 percent lower year-on-year.
For the Pacific Northwest, it said hydro generation was down because of higher than average temperatures, which lead to early snowmelt in the region.
"Genscape's monitored hydro generation [in the region] was down 24 percent month-over-month and 26 percent year-over-year," it said Monday.
Weaker winds in the region were responsible for a 15 percent decrease in the amount of energy generated from wind. Northern parts of the country with a steady wind regime witnessed minor gains in wind power, Genscape said.
The company said demand for electricity was 4 percent lower than last year because of cool summer temperatures across the Midwest and East Coast relative to last year.
"Year-to-date power demand is now 1 percent lower than 2012," the company said.
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