Guide · home battery
How does a home battery work?
A home battery stores electricity when there is surplus and returns it later when you need it. During the day solar panels often generate more than you use at that moment. Without a battery that surplus goes to the grid. With a battery you keep part of it for the evening, when cooking, lighting and appliances ask more. The right size depends on your usage, the number of panels and how much power you need later in the day. This page explains charging, discharging and the day-night rhythm. You can then calculate an initial capacity range using annual consumption. The check does not assess returns, your consumer unit or backup power.
- Charging and discharging explained
- How you store power when there is surplus and return it when you need it.
- Together with solar panels
- Generate during the day, use in the evening, or charge smartly at low prices.
- Then calculate your size
- Connect the explanation to the free capacity check for your situation.
How does a home battery work?
Use your own solar energy smarter
Solar panels generate electricity mainly during the day. Many households use more in the evening: cooking, lighting, laundry, TV. A home battery stores part of your generated power so you can use it later yourself instead of feeding it back immediately.
- Generate power during the day with solar panels
- Then store the surplus in the battery
- Use that power yourself later in the day
- Grid power remains available for any shortfall
Smart energy flow
From generation to storage and self-use
2.4 kW
Direct use
1.8 kW
Store surplus
1.2 kW
Self-use later
0.6 kW
Feed back surplus
Day & night
Charge when it is smart, use when you need it
With sufficient surplus, a battery can charge during the day. Later you use stored energy while it remains available. You still need the grid.
- Generate during the day with solar panels
- Store surplus in the battery
- Self-use in the evening
- Grid power when storage is insufficient
Charge during the day, use in the evening
06:00Morning
The sun rises
Midday
Generate & charge
Evening
Self-use
Night
Storage or grid power
Smart with energy prices
Dynamic tariffs need a separate assessment
Charging and discharging based on tariffs needs suitable controls and an assessment of costs and losses. The capacity check does not calculate trading income or payback.
- Check the contract and tariff structure
- Account for charging and discharging losses
- Assess the control system
- Do not assume guaranteed returns
Illustration of tariff periods
Lower tariff
Low
Higher tariff
High
Smart consumption
Own power
Want to know which capacity fits your home?
Calculate the suitable battery capacity for your home at no obligation, or request personal advice directly.
Calculate your capacityShort check · Free advice · No obligation