Many homeowners are using solar battery storage to gain grid independence, enhance their home solar system, save electricity costs, and contribute to sustainable living. When choosing home energy storage battery solutions, people need to decide between AC coupled vs DC coupled battery.
In this AC battery vs DC battery comparison, we will talk about what is a DC battery, what is AC battery, the pros and cons of each battery storage, and which one is ideal for home usage.
What Is a DC Battery
In DC-coupled systems, direct current will flow into a charge controller from solar panels, which will be automatically fed into the battery system. Unlike AC-coupled systems, the energy does not need to be inverted three times to be stored in the battery for later use.
When the solar panels produce electricity, it will be inverted from direct current to alternating current only once. The energy that is generated from the batteries will either flow to power the home or electrical grid.
In order to fully charge the battery from the solar panels, DC-coupled systems utilize solar charge controllers or regulators. Also, they transform the electricity flow to alternating current using a battery inverter in order to supply power to the house.
DC-coupled systems contain a hybrid inverter or a multi-mode inverter in order to regulate the battery module and solar system in one unit. The battery module and solar panels share a joint grid interconnection. As a result, the battery and solar panels are dispatched together.
DC-coupled systems perform well and are highly efficient in large-scale and commercial solar applications. Apart from the residential home battery systems, DC-coupled batteries are primarily utilized in off-grid solar installations as well. DC batteries have fewer components, so they are often preferred by homeowners due to lower costs.
Pros of a DC Battery
- DC-coupled systems are relatively affordable compared to AC-coupled systems.
- They need only one inverter and have fewer components.
- DC batteries are more efficient.
- They transform electricity only once, so there will be little to no energy loss.
- DC-coupled systems can be integrated with solar systems fully
- DC-coupled systems let solar panels produce more electricity which can be utilized for charging EVs and other appliances.
Cons of a DC Battery
- DC-coupled systems can not charge from the grid.
- They offer limited flexibility as batteries need to be installed close to the inverters.
- As there is only a single inverter, if it fails, the solar power can not be generated.
What Is an AC Battery
AC batteries or AC coupled batteries are one of the popular battery storage options, mainly for residential systems. In general, alternating current battery systems contain inverters/chargers, a lithium-ion battery module, and a BMS. AC-coupled batteries are portable, so it is relatively easy to install and upgrade the battery systems.
The AC-coupled systems come with respective inverters for the battery and the solar panels. It is possible to fully discharge the battery module and solar panels. In AC-coupled systems, battery and solar panels can be discharged independently by operating on different interconnections or jointly by sharing an interconnection to the grid.
In AC-coupled systems, direct current will flow to the inverter from the solar panels. The solar inverter is responsible for converting direct current electricity into alternating current electricity so that one can power the house.
If the AC electricity is not required or excess energy is generated, it will flow to another inverter, which will convert the AC electricity into DC. This way, the excess energy can be stored in the solar battery for later use.
When residences need energy during power outages or emergencies, the excess energy in the battery is passed through an AC-to-DC power unit. This happens in order to ensure that the generated energy is safe to power appliances in the house. The energy that is stored in an AC-coupled system has to be inverted thrice so that it can be used to power the home.
Pros of an AC Battery
- Installing these batteries on an existing solar panel system is easy, and one can expand the capacity by adding more batteries.
- Shows compatibility with different types of inverters
- As they use multiple inverters, there will be more combined power. Even if one inverter fails, other inverters will provide power.
- AC-coupled batteries can generate electricity from solar panels and the grid as well.
- They operate well with new and existing solar installations.
Cons of an AC Battery
- They are a little more expensive compared to DC-coupled systems as they use multiple inverters.
- AC-coupled batteries are less efficient compared to DC-coupled systems
- They might not be able to handle surge loads from numerous appliances.
- As the stored energy needs to be inverted about 3 times, some amount of energy is lost during every inversion.
AC or DC-Coupled Batteries for the Home Energy Storage System
To choose between an AC battery vs DC battery for the home, it is vital to consider a few factors, such as whether there is an existing solar system, budget, total power needs, etc.
AC-coupled systems are the best choice in case there is an existing solar system and want to add an extra energy storage system. They are easy to install and are compatible with all types of inverters.
DC-coupled systems are the most preferred option for those who want to install a battery storage system and solar panels at the same time. They are highly efficient, affordable, and the excess energy can be used to power EVs and many other appliances.
All-in-one Battery Energy Storage Systems offer hassle-free power to homeowners. They are compact, easy to install, offer efficient backup power, are relatively safe, and have a longer lifespan.
Can’t decide between AC vs DC coupled batteries for the home? Then, it is best to contact a professional solar installation company. Get an instant quote and professional advice from BLJ Solar.
Conclusion
The popularity of the AC-coupled and DC-coupled systems is increasing. This is because batteries allow grid independence and help in storing excess solar energy for later use during power outages or emergencies. Regardless of whether choosing an AC or DC battery, having reliable home battery storage is a great way to generate solar energy, reduce electricity costs, etc.
Make sure to invest in a high-quality home energy storage battery system so that it can store energy for a long time and work well. BLJ is an experienced solar product manufacturer offering affordable solar home batteries that have a lengthy lifespan. Reach out to BLJ Solar to acquire the best home energy storage battery systems.