Under NBT, the battery is the deal, not the add-on

If you got a solar quote before April 2023 and a storage quote now, they are not the same product with a battery bolted on. The economics changed underneath them.

Under the Net Billing Tariff, the credit you earn for exporting power to the grid is tied to hourly avoided-cost values, not the retail rate you pay. In practice that means midday solar export is worth much less than it used to be, and the money now sits in using your own production instead of selling it back. That is the battery's job.

What this does to a quote

It means a battery is no longer the optional line at the bottom. It is the part of the system that decides whether the payback math holds up.

So when an installer shows you a savings figure, the questions that matter are about the battery, not the panels:

• How much usable capacity is in the plan, and how much of your evening load does it actually cover?
• Is the system sized to shift solar into the expensive peak window, or just to provide backup?
• Does the savings estimate assume a specific rate plan, and is that the plan you are actually on?

A quote that leads with panel wattage and treats the battery as a rounding error is describing the old economics. The value moved. The paperwork should reflect it.

The buyer takeaway

Under NBT, self-consumption is where the return lives, and self-consumption is a battery-sizing question. Read the storage line first. If the installer cannot explain how the battery size maps to your evening loads and your rate plan, the savings number is a guess wearing a suit.