It’s a cloudy afternoon. The solar panels on the roof are still generating electricity, but no one is home to use it. Without a battery, that energy feeds into the grid for a few cents per kWh. With a home battery, that same electricity stays right in your home, ready to power the washing machine, the lights, or the charging station in the evening. That difference—between losing energy and saving it—is exactly what a home battery is all about.
In this article, you’ll learn step by step how a home battery works, what you need to set one up, and what to look out for before purchasing one.
Why buy a home battery?
Solar panels generate the most electricity at times when you use the least at home: around noon, while you’re at work. In the evening, when you’re actually cooking, showering, and turning on the lights, the sun is low in the sky or has already set. A home battery bridges the gap between generation and consumption.
The biggest advantage of a home battery is that you use a larger portion of your own solar energy yourself, rather than feeding it back into the grid at a low rate. In addition, a battery gives you more control over your energy bill: you buy less electricity during peak hours and use what you’ve already generated more often. For households with a dynamic energy contract, a battery can also automatically switch between periods of low and high electricity prices.
There’s also a practical side to it. With the right setup, a home battery acts as a backup during a brief power outage, and that simply gives you peace of mind. You don’t have to spend every evening wondering whether or not it’s a good idea to turn on the washing machine.
Step-by-Step Guide: How Does a Home Battery Work?
A home battery is essentially a simple system consisting of a few steps:
- Generation. Your solar panels convert sunlight into direct current (DC).
- Conversion. An inverter converts that direct current into alternating current (AC) for use in your home or sends the current directly to the battery as direct current.
- Storage. Is there more power than you’re currently using? Then the battery stores the surplus. A built-in battery management system (BMS) monitors temperature, charge level, and cell balance to ensure the battery continues to operate safely and efficiently.
- Discharge. As soon as your consumption exceeds your generation—for example, in the evening—the battery supplies the stored power back to your home.
This entire process is automatic. The system automatically controls when to charge and discharge, based on your current generation and consumption.
Choice between a home battery and a plug-in home battery
Not every home battery requires installation by a technician. There is a clear distinction between two types of systems.
A fixed home battery is integrated into your meter cabinet and connected to your solar panels and inverter. This requires professional installation but generally provides the highest capacity and the best efficiency, especially with a larger solar panel system.
A plug-in home battery is an alternative that you simply plug into an outlet. No technician is needed, and it’s quick to set up, but it has a lower capacity than a fixed system. This option is well-suited for rental properties or households that want to get started without immediately renovating.
Which option is best for you depends on your home, your solar panels, and your budget. Not sure? Our experts would be happy to help you figure it out, based on your specific situation.
Request personalized advice at
Which devices can run on a home battery?
Most household appliances can run just fine on a home battery: lights, the refrigerator, laptops, phones, a washing machine, or the router. For high-power appliances, such as an induction cooktop, an air conditioner, or an electric water heater, it’s important that your battery system’s capacity is sized appropriately. In that case, an undersized system will simply switch to grid power.
Common Mistakes
When purchasing and using a home battery, things often go wrong in a few areas:
- Incorrect sizing. A battery that is too small for the number of solar panels does not fully utilize the surplus energy. A battery that is too large costs unnecessary money.
- Assuming that every battery will continue to work during a power outage. This is not a given. Only systems with a specific backup function will continue to supply power in the event of a failure.
- Not considering the installation location. Extreme heat or cold affects a battery’s lifespan.
- Ignoring monitoring. Without insight into generation and consumption, you’ll miss opportunities to make better use of your system.
- Choosing based solely on price. A lower purchase price sometimes comes at the cost of a shorter lifespan or a shorter warranty.
Frequently Asked Questions About How a Home Battery Works
How long does power remain stored in a home battery?
Lithium batteries—the type found in most home batteries—have a low self-discharge rate. As a result, stored power remains available for days to weeks with minimal loss. Exactly how long depends on the brand, the temperature of the storage area, and whether the battery undergoes any charging or discharging cycles during that period.
Does a home battery work during a power outage?
That depends entirely on the type of system. A standard home battery is grid-connected and automatically shuts down during a power outage; this is a safety measure to prevent power from being fed back into a grid where utility workers may be active. Only systems with a specific emergency power or backup function will continue to supply power to (part of) the home during an outage. If you want to be sure of this, check whether this feature is explicitly included with the system.
What is the capacity of an average home battery?
Most home batteries for an average Dutch household have a capacity between 5 and 15 kWh, with about 10 kWh being a common starting point for many families. The ideal capacity depends on your daily electricity consumption, the number of solar panels you have, and how much of the electricity you generate yourself you want to be able to use in the evening. A larger household with many solar panels generally benefits from a higher capacity than a small household with a limited number of panels.
Lithium batteries—the type found in most home batteries—have a low self-discharge rate. As a result, stored electricity remains available for days to weeks with minimal loss. Exactly how long depends on the brand, the temperature of the storage area, and whether the battery undergoes any charge or discharge cycles during that period.
That depends entirely on the type of system. A standard home battery is grid-connected and automatically shuts down during a power outage; this is a safety measure to prevent power from being fed back into a grid where technicians may be working. Only systems with a specific emergency power or backup function will continue to supply power to (part of) the home during an outage. If you want to be sure of this, check whether this feature is explicitly included with the system.
Most home batteries for an average Dutch household have a capacity between 5 and 15 kWh, with about 10 kWh being a common starting point for many families. The ideal capacity depends on your daily electricity consumption, the number of solar panels you have, and how much of the electricity you generate yourself you want to be able to use in the evening. A larger household with many solar panels generally benefits from a higher capacity than a small household with a limited number of panels.
Want to know right away what’s cost-effective for your situation?
Curious about which storage system fits your current fixed-rate energy contract and solar panel installation? Our specialists would be happy to calculate it for you, with no obligation. Stop by our showroom in Vught for a customized demonstration, or contact us directly for a personal consultation.
Schedule a free consultation at
More than 10,000 customers have gone off-grid!