Battery Back-up Systems

Frequently Asked Questions

A battery back-up system is a modular electrical system composed of an inverter, one or more battery modules, and a logger device for remote access and monitoring. When the grid power supply is available, the batteries will be charged via the inverter. Should a power failure occur, the inverter will automatically switch over and supply your property or business with the energy stored in the batteries. The switchover happens within split seconds without any human intervention. Once the grid power supply comes back on, the batteries will return to charging mode, ready for the next cycle.

Try out out Sizing Guide here.

The rule of thumb to determining the size of your battery backup solution is to consider the home appliances or office electrical equipment you want to keep on during a power outage. Essential and non-essential loads need to be identified and agreed with the client (basically one would have to stablish between essential loads (lights, security systems, fridge, freezer, TVs, internet routers, printers, PCs, desk computers, phones etc.) and non-essential, (power-heavy loads such as geysers, stoves, air conditioning units, and machineries).

If you already have a solar system in place, AC coupling of our battery system is the logical choice. This means that the battery system plugs in to your switchboard like any other appliance and converts AC energy back to DC energy to store in the battery and converts it back from DC to AC when it is time to be used. Very little power (3-4%) is lost during the conversion process.

If you were starting from scratch and installing a new system, a DC coupled battery would make the most sense. This is because there would be no need to purchase an additional grid-connected inverter as the unit we offer can do it all for you.

Yes. These battery back-up systems are perfect for load shedding. Should load shedding occur, the inverter will automatically switch over and supply your home or business with the energy stored in the batteries. The switchover happens within split seconds without any human intervention. Once the grid power supply comes back on, the batteries will return to charging mode, ready for the next cycle.

SustainPower does not offer rooftop solar panels. Should you purchase one of our battery back-up systems and decide to include some solar panels on your roof, we will recommend you a trusted and certified electrician & solar panel installer.

3 kW Battery Inverter (Single Phase) with 2.9kWh built-in battery (modular expansion up to 17,2kWh)

3 kW Battery Inverter (Single Phase) with 2.9kWh built-in battery + additional 2.9kWh battery module (modular expansion up to 17,2kWh).  

5 kW Hybrid Inverter (Single Phase) with 11,46kWh battery storage (modular expansion up to 34,4kWh)

10 kW Hybrid Inverter (Three Phase) with 11,6 kWh battery storage (modular expansion up to 23,0kWh)

Prices are given in order, respectively to order in 6.

R 42,000 incl. VAT, excluding delivery and installation

R 65,000 incl. VAT, excluding delivery and installation

R 122,000 incl. VAT, excluding delivery and installation

R 178,000 incl. VAT (subject to change) excluding delivery and installation   

Standard Electrical Installation cost is not included in the price of the system. Installation cost is based on standard installation prices in the JHB area and includes 4h of labor with DB no more than 3m from the inverter and battery system. Installation cost are subject to change.

Standard delivery cost is R1500 and is not included in the price of the system. Please note that this is subject to change.

Installation must be performed by a qualified electrician and a Certificate of Compliance (COC) must be issued stating date of installation and electrician's registration details for the factory warranty to be valid.    

The battery backup system includes 5-year product warranty and 10-year battery warranty.

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