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Backup & off-grid

Power that stays on — with or without the grid.

PowerCube stores your solar energy and takes over within 10 ms when the grid drops out. Where there is no grid at all, it runs the site on solar and batteries alone. For larger roof arrays, SolarHub with VB5000D batteries does the same job from the wall.

Find your set-up Build it in 3D
≤ 10 ms
switchover in a power cut
3,000 W*
continuous backup output
2.5–27.5 kWh
PowerCube capacity

* With 7.5 kWh or more, or with solar supplying at the same time.

House at night with a wall-mounted hybrid inverter and battery keeping the lights on
Where it is used

Five places where the grid can't be taken for granted

Each card shows a typical starting point. Your installer sizes the final system to your loads and solar.

  • Islands

    Expensive diesel and frequent outages — run the home on solar and storage instead.

    Typical set-upPowerCube VA2000D + 2 × VB5000D

  • Cabins & holiday homes

    Lights, fridge and Wi-Fi for weekends away, with no grid connection to pay for.

    Typical set-upPowerCube VA800D + 1 × VB5000D

  • Farms

    Keep pumps, cold storage and barn lighting running far from the nearest line.

    Typical set-upPowerCube VA3000D + 3–5 × VB5000D

  • Weak-grid areas

    Ride through brown-outs and daily cuts without the house going dark.

    Typical set-upSolarHub VH2000D + 1–3 × VB5000D

  • Temporary sites

    Site offices and seasonal kiosks — installed on a level, secured base by an electrician.

    Typical set-upPowerCube VA2000D + 1 × VB5000D
How it works

One system, three states

The same PowerCube handles everyday solar storage, power cuts and full off-grid operation. Only the circuits on the dedicated backup (EPS) port are supplied when the grid is down.

  1. On-grid

    Every day
    SolarGridPowerCubeVA + VBHomeBackup loads

    Solar powers the home first, charges the battery with the surplus and the battery covers the evening. The grid fills any gap.

  2. Power cut

    Backup
    SolarGridPowerCubeVA + VBHomeBackup loads

    When the grid fails, the EPS port switches over in 10 ms or less. Solar and battery keep the backed-up circuits running until the grid returns.

  3. Off-grid

    No grid
    SolarNo gridPowerCubeVA + VBBackup loads

    With no grid at all, solar charges the battery by day and the battery supplies the site at night — up to 3,000 W continuous (with 7.5 kWh or more, or with solar).

Capacity planning

Start with your loads, then pick the capacity

PowerCube scales from 2.5 to 27.5 kWh by stacking VB5000D battery packs. The three set-ups below are illustrative starting points, not runtime promises.

Cabin

Illustrative

7.5 kWh

PowerCube VA800D + 1 × VB5000D

3,000 W backup output

Example loads

  • LED lighting
  • Fridge
  • Wi-Fi router and laptops
  • Water pump, run in short cycles

Island home

Illustrative

12.5 kWh

PowerCube VA2000D + 2 × VB5000D

3,000 W backup output

Example loads

  • Fridge-freezer
  • Lighting and TV
  • Washing machine, run in daytime sun
  • Cooking appliances, used one at a time

Farm / remote site

Illustrative

27.5 kWh

PowerCube VA3000D + 5 × VB5000D

3,000 W backup output

Example loads

  • Water pump
  • Cold storage
  • Barn and yard lighting
  • Security cameras and gate
  • With the built-in 2.5 kWh battery only, battery output is limited to 1,200 W; 3,000 W from the battery needs 7.5 kWh or more, or solar supplying at the same time.
  • Peak output of 4,500 W for 15 seconds helps with motor start-up, such as pumps and fridges.
  • Runtime depends on your loads, the season and how much solar you have. Your installer will size the system from a load list.

Prefer a wall-mounted hybrid inverter?

SolarHub VH800D–VH3000D with VB5000D batteries (5–25 kWh) suits larger roof arrays and weak-grid homes. Backup and off-grid use need at least one VB5000D.

View SolarHub
Installation & notes

Plan it properly before you go off-grid

  1. 01

    Installed by an electrician

    A single plug-in unit up to 800 W (such as SolarCore VM800WE-P2 or SolarKit) and PowerCube VA800D may be connected by the owner where local rules allow; where national rules permit higher plug-in limits, SolarCore P4 can also be connected by plug. Other SolarCore systems on an AC trunk cable, PowerCube VA2000D and above, VB5000D packs, SolarHub, ChargeFlow and EnergyPilot are installed by a qualified electrician.

  2. 02

    Stable, secured stack

    Stand the stack on a level, solid base and always fit the anti-tip kit — especially on farms and temporary sites.

  3. 03

    Assess loads and solar first

    List what must run, when and for how long, and check the solar you can fit. Off-grid systems are sized for the darkest weeks, not the summer.

  4. 04

    Follow local rules

    Grid connection, backup wiring and off-grid installations are subject to national and local regulations. Your installer will confirm what applies.

PowerCube VA with stacked VB5000D battery modules

Stack your PowerCube in 3D

Choose the VA model, add VB5000D packs and see the height, footprint and capacity before you order.

Open the 3D configurator

FAQ

Questions about backup and off-grid

Can PowerCube run a home completely off-grid?

Yes. With enough solar and battery capacity, PowerCube supplies the site on its own, up to 3,000 W continuous (1,200 W from the built-in 2.5 kWh battery alone). Size it with your installer from a list of loads and plan for the shortest, darkest days of the year.

What is backed up during a power cut?

The circuits wired to the dedicated EPS port. They switch over in 10 ms or less, so most appliances keep running. Agree with your electrician which circuits should be on the backup side.

Can I add capacity later?

Yes. Add VB5000D packs to the stack, up to 27.5 kWh per PowerCube system. For larger sites, several systems can run in parallel — talk to our team about the set-up.

Does it work in cold or hot climates?

PowerCube charges and discharges from −20 °C to 55 °C, and the battery warms itself when the cells are cold. The enclosure is rated IP66 and the VA and every VB5000D pack have built-in aerosol fire suppression.

Talk to us

Planning a backup or off-grid system?

Send us your location, the loads you need to run and any existing solar. We will suggest a set-up and, where we can, refer you to an installer in your area.

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