A1 vs Midday Saver: which tariff suits your battery?

On Synergy's flat A1 tariff, every kWh you import costs the same rate around the clock, about 33c/kWh. A battery's job here is simple: store daytime solar and release it in the evening instead of buying at that flat rate. Midday Saver splits the day into three price bands instead: a cheap solar-soak window around 9c/kWh from 9am to 3pm, a moderate off-peak rate around 24c/kWh overnight, and a peak rate around 55c/kWh through the evening. That spread is what makes forced-charging (topping the battery up from the grid during a cheap window) worth considering on short winter days, when solar alone won't fill the battery before the evening peak hits.

How do the rates compare?

A1 is one number, easy to plan around. Midday Saver rewards shifting load into the 9am-3pm window and punishes evening imports, so it only pays off if your usage pattern (or a battery) can actually move with it.

Which tariff suits your battery?

1. PV strong year-round: the battery draws mostly from solar and rarely touches the grid. A1 is simple and the flat rate is easy to plan around; Midday Saver's cheap window adds little if the battery is already full by 9am.
2. PV winter-limited: short days mean the battery may not fill before the evening peak. Midday Saver plus forced-charging in the 9am-3pm or overnight off-peak window can cost less than paying the A1 flat rate, let alone the Midday Saver peak rate.
3. Loads that run during the day (working from home, a workshop): a smaller battery can work, since PV covers daytime use directly and there's less evening peak to fill.

When is forced-charging worth it?

Forced-charging only pays when the rate you charge at is well below the rate you'd otherwise pay to import during the evening peak. On Midday Saver, both the 9am-3pm solar-soak rate (~9c/kWh) and the overnight off-peak rate (~24c/kWh) sit well under the ~55c/kWh peak rate, so topping up the battery in either window ahead of a low-solar evening is usually the cheaper path. Check with your installer before enabling it automatically: some VPP programs set their own rules for when a battery can charge from the grid.

Does a clipped export matter?

Yes, if you regularly hit an export limit. DEBS pays around 2c/kWh for exports outside the 3-9pm peak window, so solar you'd otherwise clip and send to the grid for 2c/kWh is worth far more stored and used later: avoiding an A1 import at ~33c/kWh, or a Midday Saver peak import at ~55c/kWh. Some export-limited connections cap inverter export at 1.5kW under the network's opt-out arrangement, which is exactly the scenario where a battery earns its keep by catching the excess instead of losing it to the limit.

See the tariffs overview for how A1, Midday Saver and DEBS fit together, DEBS export rates for the full peak/off-peak export breakdown, or forced-charging in practice for the settings side of enabling it. The tariff comparison calculator runs the numbers against your own usage.

Where next

Synergy Battery Rewards: what the VPP pays

Activation events credit 70¢/kWh on top of DEBS exports, and signing up is a WA rebate condition.

WA battery rebate: are you eligible?

Synergy customers get $130/kWh back, capped at $1,300.

Explore your options

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