An assessment of the East Australian Current as a renewable energy resource

Abstract

Abstract Ocean currents are an energy resource that could be harnessed to increase renewable energy yields and reduce humanity's dependence on fossil fuels. The first challenge is to identify regions of significant kinetic energy flux that are a viable distance from the shore for the extraction and transport of energy. Western boundary currents (WBCs) have been identified as the most promising resource in this regard due to their strong current speeds (typically 1–2 m s−1). However, such a resource is by necessity regional, so each prospective region requires thorough investigation. While global studies of WBCs (including the East Australian Current, hereafter the EAC) have been conducted using numerical models, they have coarse resolutions and often underestimate kinetic energy, which is the specific resource that needs accurate assessment. Here we address this knowledge gap, using a range of current velocity observations from moorings, high frequency radar and satellite altimetry to investigate the potential of the EAC as a future renewable energy resource, at various latitudes along the east Australian coast. Finally, in combination with a high-resolution data assimilating model, we propose the optimal location for future energy extraction opportunities with relatively high hydrokinetic flux (average of ~ 500 W m−2 at 50 m depth), constant direction and suitable location (25 km from shore in 400 m seawater depth).