As solar-plus-storage systems become increasingly popular, many people are already familiar with the common specifications of energy storage inverters. However, there are still a few critical parameters that are often overlooked, yet play a vital role in selecting the right product.
In this article, we highlight four important but easily neglected parameters that significantly impact the actual performance and compatibility of storage inverters.
By the end of this article, we hope you’ll be better equipped to make informed decisions when choosing among the wide range of energy storage products available on the market.
01 Battery Voltage Range
Currently, energy storage inverters on the market are mainly categorized based on the battery voltage they support.
One type is designed for low-voltage batteries, typically rated at 48V, with a voltage range of 40–60V.
The other type is for high-voltage batteries, whose voltage ranges vary, but most are designed to work with batteries of 200V or higher.
Recommendation:
When selecting an energy storage inverter, users should pay close attention to the battery voltage range supported by the inverter. It must match the actual voltage of the battery being used.
02 Maximum PV Input Power
The maximum PV input power refers to the highest power that the inverter’s PV input can handle. However, this does not represent the inverter’s maximum output power.
For example, a 10kW inverter may allow a maximum PV input of 20kW, but the maximum AC output is still only 10kW.
If 20kW worth of solar panels are connected, about 10kW of power will be lost during peak generation.
Explanation:
Taking GoodWe storage inverters as an example, they can output 100% rated AC power while storing an additional 50% of PV energy into the battery.
So for a 10kW inverter with 15kW of PV panels, it can output 10kW to the grid and store 5kW into the battery at the same time.
But if you connect 20kW of PV, 5kW of energy will still be wasted.
When choosing an inverter, it’s important to consider not just the maximum PV input, but also the actual power the inverter can process simultaneously.
03AC Overload Capability
Energy storage inverters typically have two AC output ports: grid-tied and off-grid outputs.
Explanation:
The grid-tied output usually does not support overload, since the grid provides backup support, and overload handling isn’t necessary.
The off-grid output, on the other hand, must have short-term overload capability, because there is no grid support during off-grid operation.
For example, an 8kW storage inverter may have a rated off-grid output of 8kVA, but a maximum apparent power output of 16kVA for 10 seconds.
This 10-second overload period is typically sufficient to handle the inrush current when large loads are started.
04 Communication
Energy storage inverters typically support three types of communication:
4.1 Communication with the Battery
Most lithium battery communication uses the CAN protocol, but communication protocols vary by manufacturer.
Before purchasing, make sure the inverter and battery are protocol-compatible to avoid incompatibility issues later.
4.2 Communication with the Monitoring Platform
This is similar to grid-tied inverters, typically using 4G or Wi-Fi for internet access and remote monitoring.
4.3 Communication with EMS (Energy Management System)
Communication between the storage inverter and EMS is usually via wired RS485, using the standard Modbus protocol.
However, Modbus protocol details may differ between inverter brands. To ensure compatibility, it’s best to obtain the Modbus point list from the manufacturer in advance.
Summary
Energy storage inverter specifications can be complex, and the logic behind each parameter has a significant impact on real-world performance.
Understanding these parameters is critical for selecting and using an inverter effectively.
Post time: Jul-31-2025