Solar and pumped hydro

Queensland is about to build Australia's first solar/pumped hydro storage project using a disused gold mine.  This concept has been used effectively overseas.

http://reneweconomy.com.au/2016/new-energy-gold-mine-storage-solar-pumped-hydro-75572

http://reneweconomy.com.au/2016/no-batteries-needed-pumped-hydro-for-energy-storage-79785

If it works for solar, why not wave energy?  On the coastline between Sydney and Wollongong are a network of coal mines virtually on the waters edge.  Within several hundred metres of the coast is a constant and reliable wave energy resource.

Mining has been going on for over 130 years in that area, so there are many unused mine shafts that could be utilised.

Being so close to Australia's biggest population centres would make it ideal for this type of project.  Either fresh or saltwater can be used for pumped hydro storage.  If they decided not to use saltwater from the ocean, then they could use freshwater from the three reservoirs on the plateau above the coastline, only a short few kilometres away.  Alternately, they could produce desalinated water using wave energy.