The greater the fluctuations the greater batteries become viable Take the Ballarat Battery Energy Storage System (30MW) costing 25 million for a ten year lifespan. If the battery is Charging with negative electricity prices at say $50 a megawatt 30 *50 is $1500 a day credit If the battery is discharging at peak times with positive electricity price at say $50 a megawatt is $1500 a day credit So a the battery can generate $3000 a day in energy credits for 365 days a year is 1.095 million dollars (times 10 years lifespan) is a $10.95 million payback for a $25 million price tag (this doesn't calcalate for NPV) BUT if the electricity price gets to a negative $150 while sun shines and a positive $150 during evening peak you get a $33 million payback over 10 years
The Snowy Hydro 2.0 is 350,000MWh for a 100 year lifespan So at negative 150 positive 150, the potential payback 3,832.5 trillion dollars payback over 100 years
I have removed efficiencies, running costs, maintenance etc However So i will favor pumped hydro anytime
