Solar batteries: function, benefits and products

A solar battery usually comprises numerous battery cells. The lithium-ion cells are arranged in modules and installed inside an enclosure along with a cooling and safety system. Most solar batteries are equipped with an Accelerated Processing Unit (APU), which monitors the individual cells and ensures that they all charge and discharge evenly during the battery cycles.

When it comes to energy storage, safety is the top priority – and safety starts right at the manufacturing stage. Modern solar batteries in PV systems fulfil strict safety standards and come with numerous safety mechanisms. First, the energy management system permanently monitors operation; and second, multi-stage active and passive safety mechanisms prevent overcharge, overheating, deep discharging and short circuits. Solar batteries are so robust and solid that they are incapable of catching fire by themselves or even exploding. All these safety mechanisms are specially certified by external testing institutes.

Alongside the overwhelming advantages that battery storage systems provide, there are some minor drawbacks. First, there is the issue of space. If you want to upgrade or retrofit your PV system with a solar battery, you will have to make sure that enough space is available. That said, storage solutions are thankfully becoming ever more compact without any loss of battery capacity.

Second, a battery storage system is of course an additional cost factor. The price depends on the size and storage capacity. This is why you should first review and calculate your self-consumption – for example using our solar power calculator. Businesses will need to think about overall cost-effectiveness – including original costs, saving potential and incentive options. The storage capacity should be aligned with a company’s energy requirements and capable of being expanded as and when required.

Third, your carbon footprint. A solar battery will help you to reduce your carbon footprint only if it lasts as long as possible. Correct charging and discharging are critical here.

When a solar battery is connected and installed, there are numerous aspects concerning safety, regulations and warranties that need to be considered. This is why it is best to leave the job in the hands of the professionals. After all, they know what needs to be taken into account when it comes to the connection point and to the technical requirements regarding connections to the utility grid and PV system.

Most PV systems can be retrofitted with a solar battery in order to increase the level of self-consumption and reduce dependency on the utility grid. The SMA Home Storage module is also compatible with all SMA hybrid inverters and can be commissioned quickly and easily thanks to a highly practical plug-and-play solution. The storage capacity can also be easily increased within two years with additional SMA Home Storage modules. The SMA Commercial Storage solution – an integrated storage solution for business owners – can also be expanded.

It is unfortunately not possible to say from when exactly a solar battery will start to pay off because this depends on a range of different factors. The lifetime / service life, for example, are decisive. Local electricity prices as well as costs for electricity purchased when no self-generated solar power is available also play an important role. If the storage system is properly installed and operated and aligned with your home consumption requirements, it will start to pay off in the long term in most cases. An energy advisor will provide clarity here and examine your own personal situation. Business owners should, above all, analyse their current and future energy requirements and then choose the storage capacity and technology – this will allow them to calculate the efficiency.

Before a solar battery is commissioned, it must have been properly installed and inspected to ensure that it is safe. To prevent overheating, the system must be installed in a location with sufficient ventilation and stable temperatures. During operation, regular maintenance is crucial for ensuring the long service life and high efficiency of the storage system. Overcharge and deep discharging can still shorten the service life, even if the APU is designed to prevent this.

Not only the federal government but also many federal states and municipalities offer their own incentive programs for PV systems in general and, specifically, for solar batteries. Since the beginning of 2023, new small-scale plants, inverters and battery storage systems are no longer subject to value-added tax. In addition, a variety of grants are available that differ from one federal state to the next. Here is an overview of incentive programs available in Germany, Austria and Switzerland.