Not Just Oroville - CA Hydropower Output Fell 44% In 2020
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The annual snapshot of Californias electricity generation shows how much drought conditions can affect the states power mix. In-state hydroelectricity generation in 2020 dropped 44.3 percent from the year before, according to numbers recently released by the California Energy Commission. All told, 21,414 gigawatt-hours came from a combination of the states large and small hydro power plants significantly lower than the 38,494 gigawatt-hours hydro delivered in 2019.
The states electricity from sources that do not emit carbon renewables, nuclear power and large hydro projects of at 30 megawatts or more accounted for 51 percent of generation within California last year, down 6 percent from 2019.
The change is directly attributable to the significantly reduced hydroelectric generation ... as dry conditions returned to the state, the energy commission explained in its breakdown of the numbers. Hot, dry weather sucks up water levels at hydro facilities and reduces their electricity output. Conversely, when theres plenty of rain and snow runoff, hydro generation swells.
For example, the winter of 2016-2017 saw some parts of California reporting snowpack levels of more than 180 percent of normal. Months later, the energy commission reported large hydro made up 17.89 percent of in-state generation for the 2017 calendar year. When combined with small hydro that year, hydroelectricity accounted for more than one-fifth of Californias electric generation.
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https://www.sandiegouniontribune.com/business/energy-green/story/2021-08-03/hydropower-in-california-took-a-drop-in-2020