Twenty-first century wind and solar energy potential in northern Canada

Abstract

Northern regions of Canada are of special interest for renewable energy investment due to the high cost of traditional energy generation in remote communities (Das & Canizares 2016b). However, climate variability and change have a substantial impact on renewable energy yield and system vulnerability (e.g., Ravestein et al. 2018; van der Wiel et al. 2019), and the North will experience more dramatic impacts due to climate change compared with other parts of Canada (Serreze 2015). Using the Canadian Regional Climate Model Version 4 (CanRCM4) large ensemble driven by Representative Concentration Pathway 8.5, current and future wind and solar energy potential, variability and covariability in northern Canada were assessed. Eight focal communities were additionally selected for in-depth analysis based on the work of Das & Canizares (2016b). Robust increases in annual average wind power potential (WPP) are projected across the northernmost part of the study area by 2070-2099 (up to 30%), with changes most pronounced in cold seasons. Decreases in WPP are projected for southern areas. Solar power potential (SPP) is projected to decrease across the study area, with robust changes emerging by as early as 2010-2039. For the focal communities, WPP stability (as measured through inter- and intra-annual variability) is projected to increase, while SPP stability is projected to decrease. The changes in WPP variability are associated with a dampening of the seasonal cycle of WPP in the north. Monthly mean WPP and SPP are negatively correlated, with approximately oppositely-phased seasonal cycles. Combined wind/solar installations therefore show reduced sub-annual variability, stabilizing power supplies relative to installations of solely wind or solar power. Drivers of change in WPP and SPP are complex, but changes in sea ice across the 21st century will play an important role for both WPP and SPP. Over the northern ocean regions, the influence of sea ice loss on roughness length is found to be more important than impacts on surface layer stability. Changes in storm winds also play a role, but impacts due to synoptic storm activity are difficult to distinguish from shifts in the wind speed distribution. Decreases in SPP can be attributed to projected reductions in downwelling shortwave radiation, which in turn are closely associated with changes in cloud characteristics (e.g., optical depth), as measured through CanRCM4 column liquid/ice water content. Clear-sky changes in shortwave radiation were not directly assessed, but are potentially impacted by robust increases in column water vapour. Overall, northern regions of Canada and the focal communities show high potential for renewable energy generation across the 21st century. Projected increases in wind power resources and wind power stability in the focal communities could enhance the cost-savings and emissions reductions predicted based on current climate assessments (e.g., Das & Canizares 2016b). With ever improving technologies and declining costs, the viability of renewable power in the north is likely to become even more certain in years to come.