Typical domestic customers consume less than 50% of the energy generated by their solar panel array with the remainder going out into the electricity grid for use elsewhere. Battery storage for solar panels works by simply collecting any unused energy from your solar panels and storing it in a battery instead of exporting it to the grid network. So now you can reduce the amount of money you put into your energy supplier’s pocket.

This battery independence allows you to use cheap electricity even when the sun is not shining and at the same time reduce the demands you make on the national infrastructure and hence the CO2 emissions attributable to your house. If your solar panels were installed and commissioned before the end of March 2019 you will be receiving the Export Tariff (deemed at 50%), regardless of the actual amount of electricity exported. You are being paid for the solar electricity that you generate, so it is much better to store it rather than exporting it to the grid.

With falling costs, solar panel battery storage is seen as increasingly attractive in the UK, particularly to early adopters and the 850,000 homes with solar panels.

How battery storage for solar panels works

 

Battery storage for solar panels works by diverting electricity to charge the batteries when the system detects you are using less than you are generating. This will continue until either the batteries are full, or you start using more electricity than you are generating. At that point, the batteries will kick in so you start using the stored electricity before buying more from your supplier.

All batteries store electricity as Direct Current (DC). To make the power useful, it needs to be converted to Alternating Current (AC) by an inverter. The same kind of technology that you have if you have a solar panel array.

Battery Storage System Types

 

There are two main types of battery storage system; AC-coupled and DC-coupled.

AC-coupled batteries are connected at the property’s distribution board so any energy feeding into the battery goes through the solar inverter before going into the battery. This means that any energy generated by the solar PV, stored in the battery and used in the property is converted from DC to AC through the solar inverter, back to DC to be stored in the battery and finally back to AC to be used within the property. All this converting means that there are losses within the system and that less energy comes out of the system as than was put in. This ratio of energy in to energy out is known as the efficiency of the battery system and varies between different types of batteries. In general, current battery systems are about 80-90% efficient.

DC-coupled batteries are connected between the solar panels and the solar inverter. The advantage of this is that there is no need to convert the energy generated by the solar panels as it is already in DC form and ready to be stored. There are, however, restrictions on the lengths of the strings connected into the battery and the type of inverter which means that DC-coupled storage systems need to be carefully designed before installation.

Most mainstream battery systems such as Tesla, Sonnen and Powervault are AC-coupled because they are simpler to install and can be easily retrofitted to existing systems. DC-coupled systems such as Solarwatt are becoming more popular especially with large scale commercial installations.

For your Battery Solar System Solution, let’s start the conversation, PROTECH solution has experts that can do fresh installation and run continuous maintenance and support your current battery system.