Network charges may penalise uptake of battery storage, as well as PV

“SAPN admit that batteries will reduce network peaks but still wish to charge PV households that install batteries as if they are increasing the peak,” the APVI, an independent institute, says in a newly released discussion paper.
The issue is important in Australia, which leads the world in the adoption of household rooftop solar. South Australia has the highest rate of adoption in Australia, with 28 per cent of available homes adding rooftop solar, which now contributes more than 6 per cent of the state’s electricity demand over a year.
Official forecasts suggest this will increase at least four-fold in the next decade, to the point where rooftop solar will  provide 100 per cent of the state’s electricity demand at certain times.
Hence the importance of battery storage to balance the output, and to ensure some of it used to reduce peak demand. The state government has announced a tender to install battery storage on its buildings, including Parliament House and the key arts precinct, and the City of Adelaide is also providing incentives.
The APVI says its issues with SAPN are applicable to other networks, because they face similar issues in dealing with solar and storage, and their response with tariff design.
The APVI says that SAPN recognises that the next big development is battery storage, and perhaps electric vehicles. SAPN says the “battery storage has the potential to soak up a lot of the excess energy being generated during sunshine and shift that to later in the day when the network peaks”.

The APVI criticism extends to SAPN’s proposed “cost reflective” tariffs for rooftop solar, which the APVI argues is not cost reflective at all. That’s because the the proposed demand tariff on household loads shows very little correlation between the costs charged to the customer and the customer’s demand at the time of the network peak.

The APVI notes that in SAPN’s own pricing proposal, it acknowledges the ability of solar PV – even without battery storage – to delay and reduce peak demand.