Biological and Environmental Research - Earth and Environmental System Sciences
Earth and Environmental System Modeling

Variability in Wind Energy Generation Across the Contiguous United States

TitleVariability in Wind Energy Generation Across the Contiguous United States
Publication TypeJournal Article
Year of Publication2020
JournalJournal of Applied Meteorology and Climatology
Volume59
Number12
Pages2021-2039
Abstract / Summary

ERA5 provides high-resolution, high-quality hourly wind speeds at 100 m and is a unique resource for quantifying temporal variability in likely wind-derived power production across the USA. Gross capacity factors (CF) in seven independent system operators (ISOs) are estimated using the location and rated power of each wind turbine, a simplified power curve, and ERA5 output from 1979-2018. Excluding the California ISO, the marginal probability of a calm (zero power production) is less than 0.1 in any ERA5 grid cell. When a calm occurs, the mean co-occurrence across wind turbine containing grid cells ranges from 0.38-0.39 for ISOs in the Midwest and Central Plains (MISO, SPP and ERCOT), increasing to 0.54-0.58 for ISOs in the eastern USA (PJM, NYISO, and NEISO). Periods with low gross CF have a median duration of  6 hours except in California and are most likely during summer. Gross CF exhibits the highest variance at periods of one day in ERCOT and SPP, on synoptic scales in MISO, NEISO, and NYISO, and on inter-annual timescales in PJM. This implies differences in optimal strategies for ensuring the resilience of supply. Theoretical scenarios show adding wind energy capacity near existing wind farms is advantageous even in areas with high existing installed capacity (IC) while expanding into areas with lower IC is more beneficial to reducing ramps and the probability of gross CF falling below 20%. These results emphasize the benefits of large balancing areas and aggregation in reducing wind power variability and the likelihood of wind droughts.

‘Wind drought’, ERA5 reanalysis, gross power production, net capacity factors, spatial correlation, ramps

URLhttp://dx.doi.org/10.1175/jamc-d-20-0162.1
DOI10.1175/jamc-d-20-0162.1
Journal: Journal of Applied Meteorology and Climatology
Year of Publication: 2020
Volume: 59
Number: 12
Pages: 2021-2039
Publication Date: 12/2020

ERA5 provides high-resolution, high-quality hourly wind speeds at 100 m and is a unique resource for quantifying temporal variability in likely wind-derived power production across the USA. Gross capacity factors (CF) in seven independent system operators (ISOs) are estimated using the location and rated power of each wind turbine, a simplified power curve, and ERA5 output from 1979-2018. Excluding the California ISO, the marginal probability of a calm (zero power production) is less than 0.1 in any ERA5 grid cell. When a calm occurs, the mean co-occurrence across wind turbine containing grid cells ranges from 0.38-0.39 for ISOs in the Midwest and Central Plains (MISO, SPP and ERCOT), increasing to 0.54-0.58 for ISOs in the eastern USA (PJM, NYISO, and NEISO). Periods with low gross CF have a median duration of  6 hours except in California and are most likely during summer. Gross CF exhibits the highest variance at periods of one day in ERCOT and SPP, on synoptic scales in MISO, NEISO, and NYISO, and on inter-annual timescales in PJM. This implies differences in optimal strategies for ensuring the resilience of supply. Theoretical scenarios show adding wind energy capacity near existing wind farms is advantageous even in areas with high existing installed capacity (IC) while expanding into areas with lower IC is more beneficial to reducing ramps and the probability of gross CF falling below 20%. These results emphasize the benefits of large balancing areas and aggregation in reducing wind power variability and the likelihood of wind droughts.

‘Wind drought’, ERA5 reanalysis, gross power production, net capacity factors, spatial correlation, ramps

DOI: 10.1175/jamc-d-20-0162.1
Citation:
Pryor, S, F Letson, and R Barthelmie.  2020.  "Variability in Wind Energy Generation Across the Contiguous United States."  Journal of Applied Meteorology and Climatology 59(12): 2021-2039.  https://doi.org/10.1175/jamc-d-20-0162.1.