The adoption of renewable and zero-carbon energy resources is an essential tool in climate change adaptation efforts, but the generation of energy from sources like solar radiation and wind naturally exists at the whim of the weather. California’s ambitious Senate Bill 100 (SB100) aims for 100% of California’s retail energy to come from renewable and zero-carbon sources by 2045, but questions remain about the reliability of these resources in the context of a changing climate. In particular, grid stress events like those from worsening heat waves and transmission line failures during wildfire events, as well as the push to minimize fossil gas via the electrification of buildings and use of electric vehicles, are fundamental challenges which highlight the necessity of anticipating the impacts and potential consequences of these aspirational yet unprecedented energy goals.
Eagle Rock Analytics is supporting the goals outlined in SB100 by developing high-resolution hourly profiles of photovoltaic and wind power generation potential through end-of-century for the California Energy Commission’s supply analysis team to assess climate change impacts on zero-carbon energy supply. Photovoltaic generation is being evaluated both in terms of utility and distributed (i.e., rooftop mounted in residential or commercial areas) type systems, and wind generation is being evaluated both on and offshore. Our analyses on this novel data focus on extreme days of low solar and wind energy generation which may struggle to meet demand and therefore require the deployment of other energy sources (e.g., hydropower, battery storage).
Hourly profiles of photovoltaic and wind power generation will be publicly available thanks to cloud storage made available by the Amazon Sustainable Data Initiative. Notebooks for retrieval and analysis will be integrated into the Cal-Adapt: Analytics Engine, and related data visualizations will be shared via the Cal-Adapt: Data Explorer. This work is supported by California Energy Commission grant EPC-21-037.
Natural variability in solar irradiance leads to variability in photovoltaic generation. The highlighted days show the occurrence of solar resource droughts, or those days featuring anomalously low solar energy production with respect to a long-term average.
Like solar energy production, wind power generation is subject to weather-driven variability. The highlighted days here correspond to wind droughts, also defined with respect to anomalies in the long-term average daily production.
The co-occurence of solar resource and wind droughts is called a Dunkelflaute (German: “dark doldrum”). Evaluating the severity, frequency, and duration of these extreme events in a changing climate represents a key effort in effectively adopting renewable and zero-carbon energy sources.