This depends on the timing of energy production by solar panels and the immediate energy consumption. Moreover, the storage space of the home battery plays a role in how much electricity can be stored.
Energy storage at home, through home batteries, is a key element in the transition to more sustainable energy sources. These batteries enable both households and businesses to reduce their dependence on the central power grid. The selection of an appropriate home battery depends on specific needs: is a larger model the optimal choice, or do smaller variants in certain cases offer more advantages?
In this article we explore the following themes:
- Important considerations in determining the capacity and power of home batteries
- Methods for calculating the capacity of your home battery
The difference between capacity and power #
The term "s'capacityIn tonneskWh), refers to the total amount of energy a battery can store. On the other hand, it indicatespowerOf a kind used in motor vehicleskW), at the rate at which the battery can absorb or release energy. It is important to understand that capacity and power are two different aspects of a battery.
Important considerations when choosing an appropriate capacity and power for home batteries. #
What does current and future electricity consumption look like? #
When choosing a home battery, it is important to first map your current power consumption and the power of your electrical devices. These data are crucial to determine the correct capacity and ability of your home battery.
In addition, you should also consider your future energy plans. Are you planning to switch to electric cooking, install a heat pump or purchase a charging pole? These factors play an important role in choosing your home battery.
Taking an electric car into the calculation can be complex, as the battery capacity of an electric car is usually much larger than that of a home battery. Therefore it is often not practical to install multiple home batteries just for an electric car. This aspect is therefore not included in our capacity calculations by default.
How big is the capacity of your solar panel system? #
When choosing your home battery, it is crucial to assess the total power of your solar panel installation. If the storage capacity of your battery does not meet the capacity of your solar panels, this can lead to inefficiencies. In the case of overproduction of solar energy, too small a battery can quickly become full, allowing you to send unused energy to the grid. This can be detrimental, especially if future regulations require you to pay for the return of electricity to oversupply. On the other hand, if the battery is too large, the full capacity is not used, which can also lead to unnecessary costs.
To address these challenges, it is smart to opt for a modular expandable battery. Brands such as GOODWE with their Lynx Home F Plus+ and SolarEdge with their 48V battery offer the possibility to expand in steps. This means that you can adapt the capacity to your current needs without investing directly in unused capacity. If your energy needs change, you can simply add additional modules. This ensures flexibility and efficiency in your energy management.
What are you gonna use the home battery for? #
An important aspect to consider is how to use the home battery. The needs vary greatly: someone looking for a battery for an off-grid holiday home has different requirements than someone who wants to support a 7 kW heat pump in case of power failure. At Verdasol we offer customised advice to find the best battery for your specific situation.
How do you determine the required capacity of your home battery? #
A general guideline for determining the capacity of a home battery is about 1 to 1.5 kWh per watt peak (kWp) of your PV system. For example, for a PV system of 4 kWp a home battery of 4 to 6 kWh would be recommended.
However, the actual need for storage capacity depends more on your own energy consumption than on the power of the PV system. For example, with an annual consumption of 4000 kWh, it is not appropriate to choose a home battery with more than 6 kWh storage capacity. It is important to select a battery that fits your specific energy needs well.
Important to know is that with a hybrid inverter, the maximum power the home battery can deliver is determined by the converter. For example, if you have a hybrid converter of 5 kW, the home battery can also supply up to 5 kW, regardless of whether the battery can handle a higher power.
With a separate battery converter in combination with a PV converter, such as a 5 kW PV converter and a 7 kW battery converter, you may be able to use a higher power depending on your electrical connection.
It is therefore essential to consider in your calculations not only the capacity of the battery, but also the total power of either the hybrid converter or the combination of the PV converter with the battery converter.
Verdasol advises #
There are several aspects to consider when choosing the right capacity for your home battery, and finding the most suitable brand and model. At Verdasol we have extensive experience with these processes and offer expert advice to support you in this.
