What energy storage technologies will Australia need as renewable energy penetration rises?
Wangmo Wangmo, Andreas Helwig, John Bell
Abstract
The paper reviews energy storage technologies and their applicability to the Australian National Electricity Market (NEM). The increasing dynamic variability between maximum and minimum operational demand shall continue to increase as time-varying renewable generation penetration proceeds. During this ongoing transition, severe weather events driving the NEM ancillary services market for frequency and voltage control are becoming increasingly important as the mechanical system inertia of thermal power stations reduces with ongoing retirements. As a result, the NEM's demand for energy services is becoming diversified than ever before. To maintain grid stability, various storage technologies with different response times and endurances are needed to provide grid ancillary services such as the Frequency Control Ancillary Services (FCAS) and Network Services Control Ancillary Services (NSCAS). A review of existing storage technologies for short to medium-term storage (such as flywheels, batteries, and supercapacitors) reveal that hybrid systems with different power, energy density, and fast response capabilities will be part of the solution. Pumped Hydro Energy Storage (PHES), Compressed Air Energy Storage System (CAES), and green hydrogen (via fuel cells, and fast response hydrogen-fueled gas peaking turbines) will be options for medium to long-term storage. Batteries and SCs are assessed as a prudent option for the immediate net zero targets for 2030–2050. Current challenges as well as opportunities for future research are highlighted. • The future of the electricity grid trending towards low inertia and increasing instability owing to unprecedented growth in renewable energy generation. • Increasing gap between maximum and minimum operational demand in Australia call for urgent need of balancing storage technologies. Fast response hybrid battery-supercapacitor energy storage are deemed prudent solution for the transition period, while PHES and Hydrogen are for long-term storage • The future of energy management will require a hybrid system consisting of different scales of storage technologies with highly capable convertors to emulate a conventional plant operated through virtual power plants.