If you've been researching solar, you've probably seen systems advertised as "solar" or "solar + battery" and wondered what the practical difference is. Here's a clear explanation.
Solar-Only: How It Works
A standard solar system has two main components: panels and an inverter. The panels capture sunlight and generate DC electricity. The inverter converts that to AC electricity your home can use.
During daylight hours, your home uses solar power first. If you generate more than you need, the excess flows to the grid and your retailer pays you a feed-in tariff. When the sun goes down (or when you use more than you generate), you draw from the grid at your normal rate.
Key point: Solar-only systems do not provide backup power during a blackout. By law, they automatically shut down when the grid fails (for the safety of linespeople working on the network).
Solar + Battery: How It Works
A battery system adds a third component — a battery (and typically a different type of inverter called a hybrid inverter). During the day, your panels power your home as before. But instead of excess generation going straight to the grid, it charges the battery first.
In the evening, your home draws from the battery instead of the grid. Once the battery is depleted, you fall back to grid power as normal.
Many batteries (like the Tesla Powerwall 3 and some Sungrow models) also offer backup capability — during a blackout, they isolate your home from the grid and continue powering essential circuits from stored solar.
Side-by-Side Comparison
| Feature | Solar Only | Solar + Battery |
|---|---|---|
| Day savings | High | High |
| Evening savings | Low | High |
| Blackout protection | None | Yes (with backup-capable battery) |
| Export to grid | All excess | Only after battery full |
| Typical installed cost | $5,500–$8,500 (6.6kW) | $14,000–$22,000 |
| Payback period | 4–6 years | 7–10 years |
| Suitable for daytime users | Excellent | Good |
| Suitable for evening users | Good | Excellent |
Which One Is Right for You?
Solar-only is usually the right starting point if:
- Budget is a priority and payback period matters to you
- You're home during the day and self-consume a lot of your solar
- You have a decent feed-in tariff (8¢+)
- You don't need backup power
Solar + battery makes more sense if:
- You're out all day and want to capture evening savings
- Your feed-in tariff is very low (under 6¢)
- You want energy independence and backup during blackouts
- You have or plan to get an EV
- Your state offers a significant battery rebate (Victoria's rebate can be up to $8,800)
The Hedge Strategy: Hybrid Inverter Now
If you're not ready to commit to a battery financially but want the option later, ask your installer to include a hybrid inverter (battery-ready) in your solar system. The additional cost is typically $500–$1,500 compared to a standard inverter. When you're ready to add a battery in future, you won't need to replace the inverter — just slot in the battery.
Get a Side-by-Side Projection
The best way to decide is to see both scenarios modelled against your actual electricity bill and usage patterns. Upload your bill to GridBeater and we'll show you the savings, payback period, and 25-year projection for both options.
Compare solar vs solar + battery for your home → Free at GridBeater