Technology Pathways Could Help Drive the U.S. West Coast Grid's Exposure to Hydrometeorological Uncertainty

• Published in: Earth's future 2022-01, Vol.10 (1), p.n/a
• Main Authors: Wessel, Jacob, Kern, Jordan D., Voisin, Nathalie, Oikonomou, Konstantinos, Haas, Jannik
• Format: Article
• Language: English
• Subjects: Alternative energy; Anomalies; california; capacity expansion; Carbon dioxide; Drought; Electric power; Electric power generation; Electric power systems; Electric vehicles; Electricity; Electricity distribution; Electricity pricing; Emissions; High temperature; Hydroelectric power; Hydrometeorology; Industrial plant emissions; Market prices; markets; Natural gas; Nuclear power plants; power systems; Ranking; Renewable resources; Seasonal variations; Snowmelt; Solar energy; Stream discharge; Stream flow; Summer; Summer temperatures; Technology adoption; Temperature anomalies; Uncertainty; Weather
• ISSN: 2328-4277; 2328-4277
• DOI: 10.1029/2021EF002187

Previous studies investigating deep decarbonization of bulk electric power systems and wholesale electricity markets have not sufficiently explored how future grid pathways could affect the grid's vulnerability to hydrometeorological uncertainty on multiple timescales. Here, we employ a grid operations model and a large synthetic weather ensemble to “stress test” a range of future grid pathways for the U.S. West Coast developed by ReEDS, a well‐known capacity planning model. Our results show that gradual changes in the underlying capacity mix from 2020 to 2050 can cause significant “re‐ranking” of weather years in terms of annual wholesale electricity prices (with “good” years becoming bad, and vice versa). Nonetheless, we find the highest and lowest ranking price years in terms of average electricity price remain mostly tied to extremes in hydropower availability (streamflow) and load (summer temperatures), with the strongest sensitivities related to drought. Seasonal dynamics seen today involving spring snowmelt and hot, dry summers remain well‐defined out to 2050. In California, future supply shortfalls in our model are concentrated in the evening and occur mostly during periods of high temperature anomalies in late summer months and in late winter; in the Pacific Northwest, supply shortfalls are much more strongly tied to negative streamflow anomalies. Under our more robust sampling of stationary hydrometeorological uncertainty, we also find that the ratio of dis‐patchable thermal (i.e., natural gas) capacity to wind and solar required to ensure grid reliability can differ significantly from values reported by ReEDS. Plain Language Summary In this study we model how increased adoption of wind power, solar power, batteries and electric vehicles could alter the U.S. West Coast grid's exposure to weather uncertainty. Our results show that as the mix of technologies used on the grid changes from 2020 to 2050, it will cause a “re‐ranking” of weather years (with “good” years capable of becoming “bad” and vice versa). For example, years with low wind speeds generally become more concerning (marked by comparatively high prices) as installed wind power increases. Nonetheless, the highest and lowest price years remain most strongly tied to extremes in hydropower availability (streamflow) and electricity demand (summer air temperatures) even out to 2050. In California, supply shortfalls are concentrated in the evening during periods of anomalously high temperatur