Can a Solar Battery Power Your Home at Night?

Can solar batteries power your home at night?

Solar panels only produce when the sun is shining. A hybrid inverter (for example, Sungrow’s SH-RT series) directs daytime excess into a rechargeable lithium battery. Once the generation fizzles out, the inverter seamlessly flips your home to battery power. You notice nothing—except a silent, grid-free house. Because this cycle repeats daily, the battery charges and discharges far more gently than the deep-cycling of a phone or laptop. Good systems promise 6,000–10,000 cycles, or about 10–15 years of typical household use.

What decides whether a battery can last all night?

Think of your system as a water tank and tap: how much water is stored, how fast you draw it, and how low you can safely empty the tank all matter. The main variables are:

• Usable capacity (kWh). Popular Australian home batteries range from 5 to 15 kWh; modular designs such as Sigenergy’s SigenStor let you start small and stack up to 48 kWh if life changes.

• Night-time consumption (kWh). A family running reverse-cycle air conditioning, hot-water heat pumps, and streaming devices may chew through 8–12 kWh after dark; a larger all-electric home can hit 15 kWh or more.

• Output power (kW). This is the tap size. A Tesla Powerwall, for instance, supplies up to 6 kW continuously—plenty for cooking dinner while the dryer runs, but still finite.

• Depth of discharge (DoD). Most lithium-iron-phosphate (LFP) units allow 90–97 % DoD, meaning you can safely use almost the whole battery without harming life-span.

• System design. Correct inverter selection, cable sizing, and DNSP approval protect performance and warranty.

If capacity comfortably exceeds expected overnight loads with a 10–20 % safety margin, you’ll rarely draw from the grid.

A quick solar battery sizing guide

Aim to cover your evening peak and a healthy slice of late-night baseload rather than chase 100 % self-sufficiency. Oversizing may tie up capital for little extra benefit once daytime feed-in tariffs, occasional cloudy weeks and future lifestyle shifts are factored in.

• Apartment or small home

  • Daily use: roughly 8–12 kWh
  • Suggested battery: 3–7 kWh

• Average family (three to four people)

  • Daily use: 13–20 kWh
  • Suggested battery: 7–13 kWh

• Large or all-electric home

  • Daily use: 20 kWh +
    
  • Suggested battery: 13 kWh + or a modular system

Ask a CEC-accredited installer to model at least 12 months of bills against solar production to pinpoint your sweet spot.

Do all batteries provide backup during blackouts?

Not automatically. Home battery backup in Australia needs extra hardware—often called a gateway or backup interface—that isolates your house from the grid (islanding) so lines crews stay safe. If blackout protection matters, confirm your installer includes and programs it.

Systems renowned for reliable backup include:

• Tesla Powerwall 2/3 with Gateway

• SolarEdge Energy Bank paired with SolarEdge Home Backup Interface

• Sigenergy SigenStor (whole-home or essential-loads options)

Some batteries only run critical circuits (fridge, modem, lights). Decide whether whole-of-home power is worth the extra cost.

Lithium battery chemistries in plain English

• LFP (LiFePO₄) – Used by Sigenergy, Sungrow, and many new models. Offers superior thermal stability, long cycle life and avoids cobalt. Slightly bulkier per kWh but ideal for hot Australian roofs and garages.

• NMC (Nickel-Manganese-Cobalt) – Found in the Tesla Powerwall lineage. Packs more energy into a smaller space and has an impressive track record, though it runs a little warmer and uses cobalt.

Both chemistries thrive here when installed indoors or in a ventilated weatherproof enclosure. Look for an integrated battery management system (BMS) that balances cells and monitors temperature to maximise life.

Safety, standards, and incentives

• Compliance. Battery cabinets must meet AS/NZS 51,3,9, and wiring must satisfy AS/NZS 3000. Only choose products on the CEC Approved Products list.

• Accreditation. Verify your contractor holds CEC accreditation for both solar PV and battery storage.

• Fire-service notification. Some states require lodging system details with local brigades; good installers handle this.

• Incentives. Check current schemes such as Victoria’s Solar Homes Battery Loan and the federal Cheaper Home Batteries Program, slated for July 2025. Eligibility usually hinges on CEC compliance and minimum system sizes.
  

Proper ventilation, clear labelling, and a robust shutdown procedure protect both occupants and first responders.

Solar batteries and EV charging after dark

Pairing a solar battery with electric vehicle charging unlocks deeper savings. You can top up the car overnight on stored solar rather than pricey peak rates. Remember, an EV pack (40–80 kWh) dwarfs a typical home battery. Many drivers, therefore:

• Charge the EV partly from the battery, topping up with off-peak grid power, or
• Install a larger modular battery such as Sigenergy’s SigenStor, or plan daytime workplace charging.

Vehicle-to-home (V2H) and vehicle-to-grid (V2G) remain pilot-scale in Australia but are advancing quickly.

Choosing the best solar battery for night use

1. Clarify goals. Bill savings, blackout resilience, emissions reduction—or all three?
2. Audit consumption. Use smart-meter data or an energy monitor to chart night-time loads.
3. Compare brands. Look for long warranties (10 years/≥70 % capacity), solid Australian support, and future-proof features such as modular expansion or integrated EV DC charging.
4. Insist on professional design. A CEC-accredited installer will model payback against tariff changes and export limits.
5. Plan for the long term. Roof space, family growth, and appliance upgrades can shift energy profiles—modular systems let you adapt.

The bottom line

Yes—solar batteries can power your home at night, and they do it cleanly, quietly, and increasingly cost-effectively. By sizing capacity to your lifestyle, selecting reputable technology, and following Australian standards, you can enjoy guilt-free evening comfort while protecting your wallet from rising tariffs.

If you’re ready to explore a tailored solar battery sizing guide or compare the best solar battery brands for your home, reach out to Your Energy Answers. Our friendly experts will connect you with accredited local installers, provide clear quotes, and support you on the path to energy independence.