Can I Retrofit a Battery on my Existing Solar System? | Infinite Energy

Can I Retrofit a Battery on my Existing Solar System?

While it’s almost always possible to retrofit a battery storage system on an existing solar system, the cost and ease of doing so is heavily dependent on your current set up, including if your house takes single or three phase electricity, and the size of your inverter. To find out the options available for your home and set up, select the scenario that best suits your home below.

Single Phase Power

Inverter Size <2.5kW

If your inverter is less than 2.5kW in size, it’s likely your smaller system doesn’t generate much surplus solar energy, perhaps around 1-2 units (kWh) per day. If this is the case, it means you do not have enough energy to fully charge an average sized solar battery (5-7 units are required to reach maximum charge). In this scenario, we recommend adding panels in addition to a hybrid inverter and solar battery. If you wish to keep your existing system, you’re limited to adding a smaller 2.2kW or 3kW hybrid inverter that will AC couple or “talk” with your existing inverter in WA. Infinite Energy also recommends adding additional panels, which will power both your home and new solar battery in conjunction with your existing panels.

Or, if you’d prefer a brand new system, Infinite Energy will remove your existing system and replace your existing inverter with a compatible hybrid inverter, and existing panels with one of our Tier 1 panel brands. This is the perfect option if your system is old and/or out of warranty.

However, if you’re generating around 10 units of surplus solar energy, you have more than enough energy to fully charge an average sized solar battery. In this scenario, Infinite Energy will simply retrofit a hybrid inverter and battery to your existing system.

Inverter Size 2.5-2.8kW

If you’re exporting an average of around 10 units (kWh) of power each day, you have more than enough energy to fully charge the average sized solar battery. In this case, we can simply retrofit a hybrid inverter and Tesla Powerwall to your existing system.

However, if you only generate a few spare units of solar energy per day, you do not have enough surplus energy to fully charge the average sized solar battery.

In this scenario, we recommend adding additional panels, and a second inverter which will AC couple or “talk” with your existing inverter. Both your home and new solar battery will be powered by the new and existing panels.

Inverter 2.8kW – 5kW in size

Unfortunately, retrofitting a solar battery with an existing inverter 2.8kW to 5kW in size can be a complex process, depending on the state in which you reside. In WA for example, Western Power has limited the aggregate inverter capacity for single phase homes at 5kW, meaning we’re unable to use the additional hardware required to achieve the integration of a battery.

These rules (which are governed by Western Power) may change, however the time frame could be anywhere from six months to a matter of years. The only current option is to replace your existing inverter with a compatible hybrid inverter, and to replace your existing panels.

For a greater understanding of the SolarEdge hybrid inverter technology, please see here.

Three Phase Power

All Inverter sizes

The best option for your home depends on the relationship between your current level of exported solar energy (the available surplus to charge a battery) and your ultimate objectives.

If you’re only exporting an average of a few units per day, you currently don’t have enough surplus solar energy to charge a battery. In this situation we recommend adding additional panels, and a second inverter which will AC couple or “talk” with your existing inverter. Both your home and new solar battery be powered by the new and existing panels.

If you’re exporting an average of around 10 units (kWh) of power each day, you have more than enough energy to fully charge a solar battery (most batteries require a minimum of 5-7 units to reach maximum charge). In this case we can simply add an AC coupled solar battery (such as Tesla, Sonnen & SENEC) to your existing system. 

As part of any system expansion we’re happy to offer the unique, and highly sophisticated SolarEdge hybrid inverter solution. For a greater understanding of this inverter technology, please see here.

To arrange a no obligation consultation at your home or office:

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