AC-Batteries Expanding your system?
So, you have decided to look at expanding your system by adding a battery but don’t quite know which one to go for? Let’s discuss the different options you can choose.
What Does AC and DC Power Mean?
‘AC’ stands for ‘alternating current’. This means the flow of the current moves back and forth swiftly at 50 times a second (50Hz). AC type electricity comes from the powerlines and into your house.
‘DC’, meaning ‘direct current’, is the flow of electricity in a single direction. Electrons advance from negative to positive ends. DC type power comes from solar panels and is transformed into AC power by the inverter. Once converted into AC power, it goes on to power home appliances. DC power is also in batteries e.g., AA batteries and car batteries.
What is a DC Coupled Solar Battery? What are its Advantages and Disadvantages?
DC coupled battery systems involve a hybrid inverter, consisting of a battery charger and an inverter together. Panels are installed straight into the battery system and one conversion from DC to AC power occurs. The battery charger/hybrid inverter needs to communicate and be compatible with the battery to work.
An advantage of a DC coupled system is that you do not need another inverter or charger to power the battery. The hybrid inverter can charge the battery itself.
Limitations of DC coupled battery systems include relative difficulty in communications between the battery and hybrid inverter. The battery and inverter/charger must be compatible otherwise the system will fail. If the inverter/charger brand is different to the battery brand, performance issues in the system can result in a ‘blame game’ between brands. This also makes warranty claims all the more painful.
AC Coupled Solar Batteries – Advantages and Limitations
These batteries are installed alongside your current solar PV system. The AC-Batteries has an inverter charger built in and does not require the panels to be directly connected to the battery system.
AC batteries are not generally designed for systems that are off-grid which can be a disadvantage if you plan to have an off-grid system.
The great thing about AC batteries is that they can be installed with your existing system! You don’t need to worry about compatibility between the inverter and the battery. If the inverter or battery has any issues over time, both are simple to replace, and the installation is cheaper and quicker to perform.
What Should I Choose?
If you have an existing solar system installed, an AC coupled battery is highly recommended. The installer won’t have to mess around too much with the existing system as the installation process is relatively simple and fast. This also means your current warranties on your system will remain intact.
We highly recommend the Alpha ESS AC-Batteries solution for your existing system as it is an affordable and reliable option. If you are in the market for something more premium, the TESLA Powerwall 2 AC battery system is another quality option for you.