Author(s)

Nicole Mölders^1,2, Dinah Khordakova², Ralph Dlugi³, Gerhard Kramm⁴

¹University of Alaska Fairbanks, Geophysical Institute, Fairbanks, USA.
²University of Alaska Fairbanks, College of Natural Science and Mathematics, Department of Atmospheric Sciences, Fairbanks, USA.
³Arbeitsgruppe Atmosph?rische Prozesse, München, Germany.
⁴Engineering Meteorology Consulting, Fairbanks, USA.

A method was introduced to assess the sustainability of energy production over the lifetime (~20 y) of wind turbines. Community Earth System Model simulations were downscaled for the tourist seasons (mid-May to mid-September) of 2006 to 2012 (CESM-P1) and 2026 to 2032 (CESM-P2) to obtain a reference and projected wind-speed climatology, respectively. The wind speeds served to calculate the potential power output and capacity factors of seven turbine types. CESM-P1 wind-speed climatology, power output, and capacity factors were compared to those derived from wind speeds obtained by numerical weather forecasts for reference to known standard to wind-farm managers. Juneau, Alaska served as a virtual testbed as this region is known to experience changes in wind speeds in response to the Pacific Decadal Oscillation. CESM-P2 suggested about 2% decrease for wind speeds between the speeds at cut-in and rated power, and about 8% - 10% decrease in potential wind-power output. This means that in regions of decadal climate variations, the sustainability of wind-energy production should be part of the decision-making process. The study demonstrated that using mean values of wind-speeds can provide qualitative knowledge about decreases/increases in potential energy production, but not about the magnitude. Using the total individual wind-speed data of all seasons provided the same amount of total power output than summing up the power outputs of individual seasons. The main advantage of calculating individual seasonal wind-power outputs, however, is that it theoretically permits assessment of interannual variability in power output and capacity factors. Comparison to a known standard may help stakeholders in understanding of uncertainty and interpretation of projected changes.

Sustainability of Wind Energy, Sensitivity of Wind Energy to Decadal Climate Variations, CESM, Downscaling, Interannual Variability

Mölders, N. , Khordakova, D. , Dlugi, R. and Kramm, G. (2016) Sustainability of Wind Energy under Changing Wind Regimes—A Case Study. Atmospheric and Climate Sciences, 6, 158-173. doi: 10.4236/acs.2016.62014.