AC-Coupled Battery: Why You Need It

 There are two options for the configuration of your batteries to the home energy system: AC-coupling and DC coupling. Both AC-coupling and DC coupling has its own pros and cons. In this blog, today we will explore more about AC-coupled battery storage.

What does AC coupling Mean?

An AC-coupling BESS system is a way of connecting solar panels and batteries to inverter, which converts direct current (DC) electricity to alternating current (AC) electricity. This allows you to use solar power for your home appliances, store excess power in batteries, and feed back power to the grid or use it during a blackout.

An AC coupled system requires two inverters: one for the solar panels and one for the batteries. The inverters communicate with each other by changing the frequency of the AC electricity, which regulates the power flow and prevents overcharging or overloading.

What is an AC-coupled Battery?

To tell the difference between AC-coupled battery storage and DC-coupled batteries lies in whether the electricity generated by your solar panels is inverted before or after being stored in your battery.

In an AC-coupled battery storage system, the DC power from the solar panels is first converted to AC by the solar inverter to power home appliances. Any unused energy is directed by a battery inverter/charger to charge the storage unit. In grid-tied systems, when the grid goes out, the battery inverter/charger isolates both the essential load panel and the solar inverter from the grid via an internal transfer switch.

Pros of AC-coupled Battery System

The major advantages of AC-coupled Battery Storage Systems are their compatibility and features.

AC coupled Batteries can work seamlessly with any types of solar inverters without constraints. In AC-coupled battery systems, battery faults won’t have a direct impact on the solar generation which making AC-coupled batteries are more reliable.

AC coupled batteries are flexible as they can either be dispatched together or independently, creating more options for how the system operates.