Plug-in battery vs installed home battery: which makes more sense?

Choosing between a plug-in battery and an installed home battery mainly comes down to your budget, your energy use and how flexible you want the system to be.

Both options can help you store solar power, use cheaper electricity and rely less on the grid. However, there are clear differences in price, installation, capacity and whether you can take the battery with you if you move house.

What is the difference between the two?

A plug-in battery is usually much cheaper than an installed home battery. In many cases, it can be around two times cheaper for the same storage capacity.

Another big difference is the installation. A plug-in battery can usually be installed by yourself once it arrives. This often takes around 30 minutes and means there are no installation costs. With an installed home battery, you normally need an electrician. You may also have to wait until they are available, which can take around 4 to 8 weeks.

Flexibility is also important. An installed home battery is fixed in your home, so you normally cannot take it with you when you move. A plug-in battery is much easier to take with you to a new home.

Plug-in and installed batteries compared

Plug-in battery: lower cost and more flexibility

A plug-in battery is generally cheaper to buy and does not normally require professional installation. You can usually get started quickly and the system can be easier to move if you change home.

Best suited to: households looking for a simple, flexible and lower-cost way to add battery storage.

Installed battery: a larger fixed installation

An installed home battery normally requires an electrician and costs more to install. In return, fixed systems can be suitable for higher capacities, higher power requirements and more advanced backup configurations.

Best suited to: households that want a larger permanent system or more advanced integration with the home.

Costs, capacity and installation compared

Below is a comparison between average plug-in batteries and average installed home battery systems.

Capacity	Plug-in price	Plug-in installation	Installed price	Installed installation
5 kWh	€1,200–€1,500	€0 self-installation	€5,000–€7,000	€1,000–€3,000
10 kWh	€2,500–€4,250	€0 self-installation	€7,000–€8,500	€1,000–€3,000
16 kWh	€4,250–€5,000	€0 self-installation	€8,500–€10,000	€1,000–€3,000
24 kWh	€5,000–€6,250	€0 self-installation	€10,000–€12,500	€1,000–€3,000
32 kWh	€6,250–€7,500	€0 self-installation	€12,500–€15,000	€1,000–€3,000
40 kWh	€7,500–€10,000	€0 self-installation	€15,000–€20,000	€1,000–€3,000

Prices are indicative and can vary depending on the battery brand, inverter, installation requirements and system configuration.

When does a home battery make sense?

A home battery can be useful in several situations. Most people choose one because they have solar panels and want to use more of their own solar energy. Without a battery, you might only use around 30% of the power your solar panels generate. With a battery, this can often increase to around 60% to 80%.

A home battery can also make sense if you have a dynamic energy contract. Even without solar panels, you can charge the battery when electricity is cheap and use that stored power when electricity is more expensive.

Some systems can also be used for energy trading. In that case, the battery charges when your solar panels are producing power or when electricity prices are low, and then discharges or sells electricity back to the grid when prices are higher.

Ease of use, safety and reliability

When it comes to ease of use, safety and reliability, plug-in batteries and installed home batteries are quite similar. Both usually work with an EMS system, which lets you set up and manage how the battery charges and discharges.

In terms of safety, most modern home batteries use lithium iron phosphate batteries, also known as LFP batteries. These are used in both plug-in batteries and fixed installations and are known for being safe and stable.

The expected lifespan is also similar. Most batteries last around 10 to 20 years, and many suppliers offer a product warranty of around 10 years. This makes both types of batteries comparable on these points.

Metric	Typical value
Expected lifespan	10 to 20 years
Common product warranty	10+ years
Common modern battery chemistry	LFP

Which makes more sense for your home?

In most cases, a plug-in battery makes more sense if you want a cheaper, faster and more flexible solution. You can usually install it yourself, avoid installation costs and take the battery with you if you move house.

An installed home battery can still be a good option if you want a fixed system or prefer a full professional installation. It can also be more suitable when you need higher power output or more advanced backup options.

The best choice depends on your home, your energy contract and how much storage capacity you actually need.