South-west Australia’s wave, wind and solar resources - a dispatchable power analysis to demonstrate their potential for improved energy security and reduced capital cost

The ocean wave climate along the south and west coasts of Australia possesses characteristics which make it highly valuable in combined wave-wind-solar energy harnessing. The wave resource is persistent, largely independent of the local winds and exhibits an inverse seasonal profile to the solar resource. This paper quantifies the benefits of including wave energy in a wholly renewable local power system, in terms of increased energy security, and reduced capital costs and energy storage requirements. The analysis is carried out for Albany in Western Australia and uses ten years of historical records of wind farm electrical output, solar exposure and wave buoy measurements, combined with a CorPower Ocean wave energy converter power matrix. The daily power output timeseries, from each standalone and hybrid system, is used to calculate the minimum energy storage capacity required in order to guarantee power supply above a dispatch threshold. Key findings are that integration of wave energy consistently reduces energy storage needs, compared to a standalone solar farm, with the maximum reduction reaching over 90%. Economic assessment was carried out using 2050 capital cost projections for the three generation technologies (wave, wind, solar) and multiple energy storage options including batteries, pumped hydro, molten salt and hydrogen. Significant cost savings of up to 80%, compared to standalone PV, can be achieved in hybrid wave-solar systems with high dispatchability. Systems using hydrogen tanks and molten salt for energy storage were the most economical. These results suggest a potentially significant benefit of incorporating wave energy into national energy planning.