A lot has, is and will be written about the potential returns on investment in battery storage. Some analysts say the payback will be quick – within 6 years in some areas – others say that returns will be beyond 10 years and won’t become mass market before 2020.
That makes this graph from the Clean Energy Finance Corp particularly interesting. It notes that there are 160,000 or so households in NSW that are currently receiving a premium tariff of 60c/kWh for their solar output (plus a retailer bonus), and these tariffs will finish in January 2017.
By then, the solar systems they installed will have paid for themselves. The question for these household then becomes, what to do with the surplus electricity produced by the arrays, particularly given that tariffs are only voluntary, or around 6c/Wh or 8c/kWh at best?
Battery storage may be an answer.
This graph below from Simon Brooker, the executive director of corporate and project finance for the Clean Energy Finance Corp, suggests that the returns could be quite good, and that battery storage added to rooftop solar systems will still be competitive and even beat grid-based tariffs.
Even these assumptions could be seen to be conservative, given that battery storage prices are likely to fall well below $1,300/kWh – particularly by the end of next year.
“We are not talking 40c/kWh or 50c/kWh. We are talking much more interesting numbers,” Brooker noted.
Morgan Stanley analyst Rob Koh said the key for battery storage take-up would also be on the structure of tariffs set by utilities, including time of use tariffs, the level of fixed and locked in payments, and newly mooted capacity payments.