Demand charges are based on your highest 30-minute draw, so one peak half hour can set the bill. A solar battery for businesses discharges at that moment to shave the peak, while solar cuts the daytime energy you buy. RESINC Solar & Batteries cites demand charge savings of 15% to 25% in its commercial solar guide.
● Demand charges on the Ausgrid network are based on your highest 30-minute draw, so a single peak can set the charge
● Solar cuts daytime energy use, but a battery with smart control is what shaves the peak itself
● Typical paybacks are 3 to 5 years for most commercial solar systems and 6 to 8 years for batteries
● Energy management software schedules battery charging and discharging and tracks several sites from one dashboard
● The federal battery rebate reaches businesses, with around 30% off eligible 5 kWh to 100 kWh batteries and the next reduction due on 31 December 2026
Peak demand charges are a network fee based on the highest demand your site draws from the grid. On the Ausgrid network that covers the Central Coast, the charge is based on your highest 30-minute draw.
That is why they hurt. Your energy bill rewards total usage, but a demand charge punishes a spike. A workshop starting several machines at once, air conditioning working hard on a hot afternoon or a row of EV chargers plugging in together can set the charge, even if the rest of the period is quiet. Cutting the peak therefore matters as much as cutting the total kilowatt hours.
Commercial solar PV panels reduce the energy you buy in the daytime, and typical peak solar generation runs from 9am to 3pm. That is valuable for a site with strong daytime use. Central Coast Stadium, for example, is projected to use 88.4% of its solar onsite, according to the case study.
Demand charges are different. They depend on a single peak interval, and that interval can fall on a cloudy morning or after the panels have stopped producing in the late afternoon. Solar helps when the peak coincides with strong sunshine and does little when it does not. That gap is where a battery earns its place.
A solar battery for businesses stores energy when it is cheap and releases it when the site would otherwise draw heavily from the grid. Commercial batteries can charge from excess solar or, without solar, from off-peak grid power, and software then dispatches the stored energy when demand or prices justify it. Applied to your own site, the same logic lowers the highest draw the network sees.
Control is what separates a battery that cuts demand charges from one that does not. A battery that empties early in the afternoon has nothing left for a late-afternoon spike. Automated schedules, set from your real load data, keep enough charge in reserve for the moments that matter, which is why the software and the sizing matter as much as the hardware.
The commercial solar guide gives these typical ranges. They are vendor estimates, not a quote: