Battery storage systems are increasingly mentioned alongside solar power plants. However, simply connecting a battery to the power plant does not mean complete independence from the power grid. A storage system will only be beneficial if it is selected based on actual consumption, existing or planned equipment, and a clear objective.
In some homes, storage systems are needed to use the electricity generated during the day in the evening. For other households, it’s important to have a backup in case of a power outage. In still other cases, a battery is planned in conjunction with an electric vehicle charging station, a heat pump, or a smarter whole-home energy management system. All of these goals are different, so the most suitable solution for each home will be unique.
The benefits of a battery depend on when electricity is consumed
A solar power system generates most of its electricity during the day. However, many households consume more electricity in the morning and evening, when solar production is lower or nonexistent. In such cases, a storage system can store excess energy generated during the day and release it later, when more appliances are turned on at home.
Therefore, when planning a storage system, it is important to consider more than just total annual energy consumption. Hourly consumption data—or at least data on daytime and nighttime usage—provides much more insight. For example, two seemingly identical homes may consume the same amount of electricity over the course of a year, but in one, peak load occurs during the day, while in the other, it occurs in the evening. In such cases, the requirements for the battery storage system will differ as well.
Is a large battery capacity the best solution?
In many cases, capacity is the main factor used to evaluate a storage system. However, a larger capacity does not always mean greater benefits. If the battery is not regularly charged and discharged, part of its capacity remains virtually unused. When assessing household needs, consider whether there is excess electricity during the day, and, if so, how much excess there is and what the evening load is like.
What should you know in advance when planning a backup power supply?
Some people expect that installing a home battery will ensure a continuous power supply during a grid outage. However, not every combination of a solar power system and a battery automatically provides backup power. This requires the right equipment, control solutions, and clearly defined loads.
In most cases, it isn’t practical to power the entire house as if the grid were operating normally when the power goes out. It’s more practical to select the most important circuits in advance: the refrigerator, lighting in certain rooms, communication equipment, gates, circulation pumps, or other essential devices. This way, the same battery can provide a longer and more stable backup.
Therefore, it’s worth thinking in advance about what will happen if the power goes out. It is important to know how long it will take for the system to switch over, the maximum allowable backup load, and whether the solar panels can charge the battery while the system is switching. Without this information, the promise of autonomy may remain just that—a promise.
How do you choose the right inverter and control system?
The battery's capabilities depend heavily on the inverter and energy management system. If the solar power plant is already installed, before selecting a battery, verify whether the existing inverter is compatible with the battery, whether any additional components are needed, and whether the backup power function will be supported.
If you’re still in the planning stages of your solar power system, it’s worth considering a hybrid inverter from the very beginning. It’s important to evaluate the rated power, compatible battery models, energy flow management, expansion options, and the manufacturer’s software.
If you choose the cheapest solution for your solar power plant, you may encounter obstacles later on if you need a storage system, backup power, or more advanced management capabilities.
When is it not worth rushing to choose a storage system?
A battery storage system is certainly not essential for every solar power plant. If a large portion of the generated energy is already consumed during the day, power outages are rare, and backup power isn’t a priority, the investment's benefits may be questionable. Therefore, before investing in a storage system, it’s worth optimising your consumption schedule or adjusting the power plant's operations.
What should you look for when choosing a battery?
When evaluating offers, it’s not enough to simply compare the manufacturer, capacity, and price. You should clearly understand how the battery will be integrated into an existing or new solar power plant, its usable capacity, charging and discharging power, backup power limits, and who will be responsible for system startup and maintenance.
It’s worth checking whether an additional battery module can be added later, how the app works, where data is stored, and how the system will behave if the internet connection is lost. These details will determine how easy it is to manage the storage system.
A well-chosen energy storage system can increase the share of solar energy used in your home, give you more control, and, in certain cases, provide a backup supply. Not sure where to start? Pinus LT specialists will analyse your consumption data and help you choose a storage system suitable for your existing or planned solar power plant.