Assessment of solar and wind resource synergy in Australia

Abstract

Solar and wind generated power is expected to increase drastically in the future. Unlike fossil fuels, however, solar and wind resource extraction introduces challenges of variability and intermittency. Several recent studies around the world have shown that since dissimilar climatological factors are responsible for wind and solar resources, they can often operate in tandem to offset lulls in each other. While most research on solar and wind resource interaction has been undertaken over the Northern Hemisphere (America, Europe and China), there is a lack of understanding on how much (or even if) solar and wind resources complement one another in other parts of the world. To partially address this issue in the Southern Hemisphere, this study provides a systematic quantitative analysis of the complementary characteristics of solar and wind resources on the Australian continent. As such, wind power density and surface incident shortwave flux are derived from the hourly Modern Era Retrospective Analysis for Research and Applications (MERRA) product for the entire continent for the period from 1979 to 2014. It was found that the temporal synergy between solar and wind resource is maximum along the western and southern coast of Australia. Tasmania, south-eastern (parallel to eastern Great Dividing Range), and northern regions (Cairns and Kimberley Plateau) of the continent also showed significant synergy (≈40% within a distance of 93km), which was mostly influenced by hours of daylight when the solar resource is available. Increasing the spatial extent increased the occurrence of synergy characteristics to 50% within a distance of 465km. These findings are significant because most of the synergy (and intermittency) in solar and wind resources was found in proximity to transmission lines – locations where renewables are likely to be cited going forward. Amongst current large-scale solar and wind farms operating in south-eastern Australia, this study also finds that increased power production is possible by balancing existing assets with complementary solar and wind farms. While these results are limited to a single continent, the proposed approach (e.g. using similar metrics) can be readily applied to investigate synergies between solar and wind resource in other parts of the world using the global MERRA product.