Solar PV and Batteries complement each other well. Recent advancements in technology have made solar battery systems more efficient and customizable. This is great news for consumers that are looking to purchase a Solar Battery System, but what about consumers that have already invested in a Grid-Tied Systems without batteries?

We can convert existing Grid-Tie Systems into 48 Volt Solar Battery Systems under the following conditions:

I. The previously installed Solar Grid-Tie System utilizes a string inverter system. Microinverter systems can also be utilized in Solar Battery Systems but the equipment will run at a lower efficiency compared to systems running on a SMA string Inverter. String Inverter brands outside of SMA will also run at a lower efficiency because they will not be fully compatible with the SMA Sunny Island Off grid Inverter‘s Frequency Shifting Technology.

When the solar power produced exceeds the power consumed, the Sunny Island fluctuates the frequency of the SMA String Inverter to continue solar production. When other Inverter (including Microinverters) brands are utilized, the Battery Inverter will have to shut off the solar Inverter when solar power produced exceeds power consumed and in some cases (depending on the Battery Inverter) the entire electrical system will shut down if diversion loads aren’t created.

This means that if you have a different brand inverter than SMA, you will have to replace the string inverter with an SMA product or use less compatible equipment.

II. A location must be allocated for Battery Storage. Solar Batteries need to be kept in a dry area with stable air temperatures. In some cases we store the batteries outside in an insulated weathertight container. In other cases, the batteries can be stored in your garage or other empty spaces.

III. The extra Battery Inverter(s) required for a Solar Battery System will need to be located in a dry area.

IV. The Solar PV System Owner will need to decide what they want to be backed up by the battery system. What do you want backed up? A few lights? A refrigerator? The whole house? The price will vary dramatically by what you back up. Most homes were designed to run on the grid and they consume too much electricity for a complete battery system to be feasible. In some cases a generator can be incorporated into the system.

In Conclusion

We recommend SMA Sunny Island Systems when a solar production meter is used (Austin Energy, Oncor, CPS). A Solar Battery System utilizing a Sunny Island acts as a conventional Grid-Tie System when the grid is available. When the grid loses power, the Sunny Island acts as a UPS and immediately feed to critical loads using both battery and solar power.  The Outback Radian, Schneider Conext XW, and Magnum Hybrid Inverter systems can be utilized if the solar pv system does not have a solar production meter (PEC, Bluebonnet). More information on Solar Battery Systems can be found on our Solar PV System with Battery Backup page.