Exploring the Complementarity of Offshore Wind Sites to Reduce the Seasonal Variability of Generation

Abstract

Wind energy is a powerful resource contributing to the decarbonization of the electric grid. However, wind power penetration introduces uncertainty about the availability of wind energy. This article addresses the complementarity of remote offshore wind sites in Brazil, demonstrating that strategic distribution of wind farms can significantly reduce the seasonality and the risk of periods without generation and reduce dependence on fossil sources. Field observations, atmospheric reanalysis, and simplified optimization methods are combined to demonstrate generation improvement considering regions under environmental licensing and areas not yet considered for offshore development. Aggregated power results demonstrate that with the relocation of wind turbines, a 68% reduction of the grid seasonal variability is possible, with a penalty of only 9% of the generated energy. This is accomplished through optimization and the inclusion of the northern region, which presents negative correlations with all other stations. More specifically, the north and northeast of Brazil have large seasonal amplitudes. However, out-of-phase wind regimes with a strong negative correlation (R < −0.6) and high-capacity factors (CF) during the peak seasons occur in Jan-Feb-Mar in the north (CF > 0.5) and in Aug-Sep-Oct in the northeast (CF > 0.7). These complementary regimes allow for the introduction of the concept of Reserve Wind Power (RWP) plants, wind farms that can be viewed as “reserve sources” for energy security. These can replace the contracts of thermal reserve plants, with resulting economic and environmental advantages. Our analysis suggests that RWP plants can be 20 to 32% cheaper than thermal reserves in the current market.

Characterization of Wind Resources of the East Coast of Maranhão, Brazil

“…ERA5 has been previously validated with towers [47], LIDAR wind profilers [48] and different locations worldwide [49]. ERA5 was validated regionally with observations of the Alcântara Launch Center tower and EOSOLAR datasets [5,18,50].…”

“…It fluctuates at different timescales and its magnitude changes with the geographical location and terrain characteristics [1]. Changes on the timescales of hours to days impact the operation of power networks [2], while fluctuations on the scale of months to years are essential for resource assessment and long-term planning [3][4][5]. Atmospheric stability, turbulent intensity and vertical shear are important characteristics that affect the performance and fatigue loading of turbines [6][7][8][9].…”

Assessing Economic Complementarity in Wind–Solar Hybrid Power Plants Connected to the Brazilian Grid

“…The winds are more intense in the months of July to December. This can be explained by the drier weather, which favors an increase in wind intensity due to higher atmospheric pressure gradients, combined with the northward movement of the Intertropical Convergence Zone (ITCZ), which intensifies the trade winds along the eastern coast of Maranhão [30].…”

Offshore wind power around the Iberian Peninsula: variability, complementarity and added value for the power system

“…Previous studies have analysed temporal variability of the wind resource at different time scales [15,[21][22][23]. Spatial complementarity among the different installation sites can be used to smooth out the temporal variability of the combined power supply [24][25][26][27][28][29][30][31][32].…”