Battery Storage System for Solar PV

Use more of your Solar PV with Battery Storage.

Green Solar World Ltd. offer a range of battery storage systems to complement solar PV installations.

The solar PV system on your roof will generate electricity during the day that you can use in your home. Without a means of storing that solar electricity, any surplus energy that you do not use is “exported” to the grid. During times when the panels are no longer generating, you need to buy electricity from your electricity supplier.

Battery storage system lets you store the surplus solar electricity instead of exporting it. This reduces the amount of grid electricity you need to buy, saving you money on your electricity bill. But batteries are not for everyone, as you generally need to be generating 'surplus' solar electricity to store. It is also important to note that, contrary to expectations, some battery storage systems are not designed to work during power-cuts and it may affect your Feed-in-Tariff income as well.


If you have a battery storage system enquiry give one of our experts a call on 01638 428 974

How a battery system works?

During the day:

  • the solar PV system generates solar electricity
  • the battery storage system will check if all generation is being used to power your lights and appliances
  • if you are not using all the electricity that the solar PV system is generating, then the system will ensure that any surplus energy is used to charge the battery
  • once the battery is fully charged, if there is still more solar electricity being generated, this will be exported to the grid (or in some systems, will be diverted to other uses e.g. to an immersion heater)

In the evening or at time of low solar generation:

  • the solar PV panels have a reduced or zero output
  • the battery system can discharge the stored electricity, providing you with renewable-generated electricity at no additional cost
  • once the battery is discharged, if you need to use more electricity, you buy it from your electricity supplier

The Batteries

The two types of batteries most commonly offered for solar PV storage in the home are lithium-ion and lead-acid batteries.
The key features and differences are:

Lithium-ion batteries

  • more expensive
  • increasingly common in domestic grid-connected solar PV storage systems
  • lighter
  • require integrated controller, that manages charge/ discharge
  • more efficient
  • can discharge more stored energy
  • longer expected life

Lead-acid batteries

  • cheaper
  • typically used for off-grid properties where more storage is required
  • heavier and larger
  • need good charging and discharging routine to maintain battery health
  • less efficient
  • shorter expected lifetime

Typical lead-acid battery systems may be set up to limit the 'depth of discharge' to around 50%, lithium-ion battery systems to 75% or more.

What a battery storage system could power

A fully-charged medium-sized system could store sufficient energy to power during evening your lights and lower-powered items like your fridge-freezer, TV and laptop over four or five hours. However, the battery will quickly run out if you put on heavy energy users like the washing-machine or tumble dryer (these can consume 2 – 3 kWh in a single use).
In winter the battery might not store enough to provide for even the lower-powered items for many hours.

Battery lifetime

A battery's efficient lifetime depends on the technology and the way the battery is used. It is worth to note that solar PV panels can last 25 years or more. The storage battery is likely to need replacing in the lifetime of your PV system.
Important Note: There is no MCS standard for battery storage systems so you will not find an MCS-certified system but you should make sure that the installer of your storage batteries for solar PV systems is a qualified electrician.

01638 428 974
078 401 850 75

Green Solar World LTD
Workshop 3
Newmarket Business Centre
341 Exning Road