What Is Home Battery Storage?
Home battery storage allows electricity to be stored and used later instead of having to use it at the exact moment it is generated.
When combined with solar panels, a battery can store surplus solar electricity during the day and make that energy available later when the sun is no longer producing electricity.
Modern home batteries can also be used in different ways depending on the system, tariff and installation.
Key Insights & Understanding
How Does a Home Battery Work?
A home battery stores electrical energy and releases it when required.
With a solar and battery system, the basic process can be:
Solar panels generate electricity → your home uses the electricity → surplus electricity charges the battery → stored energy is used later.
The exact way a system operates depends on the battery, inverter, energy management system and configuration.
- Battery Capacity vs Power
Capacity and power are two different things.
Capacity, measured in kWh, tells you roughly how much energy the battery can store.
Power, measured in kW, tells you how quickly the battery can charge or discharge.
A battery with a large capacity but low power rating may store a lot of energy but deliver it more slowly.
The right combination of capacity and power depends on your household's electricity usage and how you plan to use the battery.
What Does kWh Mean?
Battery capacity is normally measured in kilowatt-hours, or kWh.
For example, a 5kWh battery has a nominal storage capacity of around 5kWh.
However, the amount of energy you can actually use can depend on factors such as the battery's usable capacity, state of charge, operating limits and system settings.
A bigger battery is not automatically better.
The right size depends on your electricity usage, solar generation and how you intend to use the battery.
UKPTH Takeaway
Home battery storage lets you store electricity for later use, but the right system depends on how you use electricity, how much solar you have and what you want the battery to do.
Understanding capacity (kWh), power (kW) and how the system operates is essential before choosing a battery.