Guidance on How to Select Solar Battery Energy Storage System

The combination of solar plus energy storage bring the long-term sustainable development momentum for PV energy. How to choose a suitable solution for photovoltaic plus energy storage? How to operate the solar storage system efficiently? This article will introduce them to you.

What are the types of energy storage system?

Energy storage refers to the process of storing energy through a medium or device and releasing it when needed.

Traditional energy storage technologies are divided into the following types

• mechanical energy storage

• electrochemical energy storage

• chemical energy storage

• electromagnetic energy storage

• thermal energy storage

At present, electrochemical energy storage are used widely for residential PV and Industrial.

What is Electrochemical energy storage?

Electrochemical energy storage is an energy storage technology and measure that uses chemical batteries to store electrical energy and release it when needed.

Types of battery energy storage

In solar energy storage, electrochemical energy storage method can be divided into lithium battery, lead-acid battery, lead-carbon battery, flow battery and sodium-sulfur battery energy storage.

Among them, lithium battery and lead storage battery (the general name of lead-acid battery and lead-carbon battery) It is the most widely used electrochemical energy storage technology route for industrialization.

Comparison between lithium solar battery and lead-acid battery

With the development of battery technology and the rapid decline in cost, lithium batteries have become the mainstream choice in household energy storage projects, and the market share of new chemical batteries has reached more than 95%.

Compared with lead-acid batteries, lithium batteries have the advantages of high efficiency, long cycle life, accurate battery data, and high consistency.

How to choose the suitable battery storage for solar system?

 Assume that to set up a home solar energy storage system. The daily electricity consumption is expected to be 20 kilowatt-hours (kWh), and it is hoped that the system can still provide electricity when the number of consecutive rainy days is 3 days.

Firstly, determine the capacity of storage battery. In this situation, the total capacity of battery module should be 60kWh.

Then, determine the specifications of the solar panel. According to the actual lighting conditions, it is assumed that the average daily sunshine time is 5 hours.

To meet the demand of 20 kWh per day and simultaneously charge the energy storage battery, the solar panels should be rated at least hourly electricity usage / sunshine hours = 20 kWh / 5 hours = 4 kW.

So, in this example, choosing a solar panel rated at 4 kW would be appropriate.

Please noted that this is just a simplified example. There are a lot of factors should be taken into considerations.

In Conclusion

The selection of solar plus battery energy storage system should consider factors such as system efficiency, illumination changes and seasonal changes. For more information, please contact us.