Meteorology and Climatology of Historical Weekly Wind and Solar Power Resource Droughts over western North America in ERA5

Abstract

Wind and solar electricity generation is projected to expand substantially over the next several decades due both to rapid cost declines as well as regulation designed to achieve climate targets. With increasing reliance on wind and solar generation, future energy systems may be vulnerable to previously underappreciated synoptic-scale variations characterized by low wind and/or surface solar radiation. Here we use western North America as a case study region to investigate the historical meteorology of weekly-scale “droughts” in potential wind power, potential solar power and their compound occurrence. We also investigate the covariability between wind and solar droughts with potential stresses on energy demand due to temperature deviations away human comfort levels. We find that wind power drought weeks tend to occur in late summer and are characterized by a mid-level atmospheric ridge centered over British Columbia and high sea level pressure on the lee side of the Rockies. Solar power drought weeks tend to occur near winter solstice when the seasonal minimum in incoming solar radiation co-occurs with the tendency for mid-level troughs and low pressure systems over the U.S. southwest. Compound wind and solar power drought weeks consist of the aforementioned synoptic pattern associated with wind droughts occurring near winter solstice when the solar resource is at its seasonal minimum. We find that wind drought weeks are associated with high solar power (and vice versa) both seasonally and in terms of synoptic meteorology, which supports the notion that wind and solar power generation can play complementary roles in a diversified energy portfolio at synoptic spatiotemporal scales over Western North America.

Assessing the relevance of renewable energy resources availability for the existence of Energy Cooperatives in Europe

“…In our case, the indicators are related to RES availability and quality. We consider a total of 38 indicators, which calculation is motivated by the work of Brown et al [12] and Jurasz et al [13]. The former evaluated wind and solar power resource droughts for western North America at the weekly scale and the latter assessed wind and solar power complementarity and resources droughts for Poland at the daily scale.…”

“…These capacity factors are calculated as free of assumptions on technology as possible, to keep the generality of the results. This follows the line of arguments of [12,13], and we use the calculations proposed by Bett and Thornton [19].…”

“…The third set of indicators comprises multiple alternatives to quantify RES droughts (Table 3). The calculation of the droughts is also motivated by Brown et al [12] and Jurasz et al [13] and therefore we provide indicators at the daily and weekly scale for the capacity factors of PV and wind power individually as well as assuming a combination of both in equal proportions. We assume that a day with a drought is a day when the average capacity factor from all hours of that day belongs to the lowest 1% of all days in the entire time series.…”

A copula-based assessment of renewable energy droughts across Europe

“…The authors quantified the occurrence of energy droughts of renewable production when daily wind and solar power was less than half of the climatological mean. Recently, [18] examined the climatology and synoptic conditions linked to extreme reductions of wind and solar production at weekly time-scales over western North America. They identified co-variability between wind droughts and higher than average solar power, due to the seasonal cycle and synoptic conditions, which highlights the need for energy-sharing resources (i.e.…”

Meteorological Drivers of Resource Adequacy Failures in Current and High Renewable Western U.S. Power Systems

“…The first literature analyzes meteorological drivers in the power system, but does not consider RA, a gap that we fill. Within this set, a few studies examine meteorological drivers of periods of low renewable generation or high net demand (demand minus renewable generation) [30][31][32][33]. Meteorological drivers in these papers include surface meteorology and atmospheric circulation during these periods.…”