Powervault 3 solar battery technical specification

Powervault 3 home battery storage is designed and assembled in the UK. It's been designed specifically to store solar energy or off-peak electricity in either residential or commercial premises. It’s compatible with all solar systems and is quick and easy to install. It comes with a hybrid solar inverter, which can replace your old one now or be ready for switch over when your old one fails, saving you the replacement cost of that too. You can view and download the full specifications here

Battery type and chemistryLithium-polymer (Li-MNC)
Usable capacities4.1kWh8.2kWh
Usable inverter rating4.6kW5.5kW
Available with EDF Energy grid services

H: 90cm; W: 98cm; D: 25cm

An additional 10cm is required on all sides for access

H: 120cm; W: 98cm; D: 25cm

An additional 10cm is required on all sides for access

Warranty 10 years

Need more help? Contact us

If you're not sure which option is best for you, or would like to talk through the technical information in more detail, we'll be more than happy to discuss your requirements and guide you through the process. Our Tech Team are very knowledgeable and will help you decide. They're a busy team so to save you waiting on the phone, please fill out the contact form below, including best day and time to contact you and they'll give you a shout!


Installation of your Powervault 3 home solar battery is included as part of the package we offer. The Powervault 3 can be installed in most internal locations, such as garage, utility room, basement or under the stairs. It's not suitable for external locations and we don't recommend installing it in loft spaces. Powervault 3 will be floor mounted and fixed to the wall for stability. It'll need to be connected to the internet at all times. As part of the pre-installation process we'll ask you for measurements and photos of the proposed location and of the fuse box. 

The Standard Installation covers all the work we need to do for the average domestic installation. For more complex installations or those in more geographically remote locations we charge the additional costs as detailed in the Installation section of the Ts&Cs.

Go to our Frequently Asked Questions for more information. 

Watch video: Powervault 3 - home solar battery

View your savings

Powervault portal on iPad

As part of the installation we'll set up your Powervault Portal, which enables you to see your solar generation, battery charge and discharge and energy usage on daily basis. 

EDF Energy grid services

What are EDF Energy grid services?

Right now, when the electricity grid runs short of capacity during peak periods, extra power can be generated but usually not in the cleanest or greenest way.  Conversely, when there’s excess renewable generation, demand cannot be increased which leads to wasted energy. That’s why EDF Energy is building a network of small-scale batteries to help balance this mismatch. In return for helping balance the grid for 10 years, we’re offering a substantial upfront discount off the retail price of the battery. You can also purchase Powervault at full retail price and opt out of the grid services.

Engineer looking up at a electricity pylon

Are Grid Services new?

Grid services already exist in industrial and commercial energy markets. National Grid and the District Network Operators pay for grid balancing services to minimise risk of blackouts due to supply-demand mismatch. As an example, a factory that uses a lot of electricity may be paid not to operate during a period of high energy demand or when the local network is under strain. Owners of large scale batteries can also be paid to soak up excess generation or release when top up levels are required. The unit rate charged for the electricity bills for large commercial properties can vary every half hour (higher rates at times of peak demand) so commercial scale storage can be deployed to be used at peak hours, reducing the need to draw expensive energy from the grid.

Why is EDF Energy selling domestic scale batteries?

It would be difficult for a single domestic scale battery to operate in the same manner as large commercial businesses: requiring half hourly billing, a plethora of contracts, and a means to control the battery in response to the signals from the grid. This is why we’re building a network of small-scale batteries, which when aggregated together can be utilised like large scale storage to help manage the peaks and troughs of energy production and customer demand for energy, thereby supporting the growth of renewables and small scale generators.

The grid services contract with the domestic battery owner is for ten years. We pay the battery owner upfront for access to the battery, in one lump sum as a discount off the price of the Powervault 3 battery (£1,560 for 4.1kWh or £2,060 for 8.2kWh battery, respectively). This is equivalent to £150 or £200 per year across the ten years of the grid services contract, depending on battery capacity. We recognise that investing in a solar battery can be a significant expense for householders, so we have given the discount upfront rather than a payment per year. Grid services with home solar batteries form a new part of the energy ecosystem, so we’re taking the financial risk on return, rather than the battery owner. 

How will grid services work with my individual battery?

The home batteries will all operate as a group, not individually, so an individual battery will not be responding to peaks and troughs of the grid by itself. As an example, in 24 hour period, the householder may see additional charge being fed to the battery during the night if there was excess wind energy available on the grid, but there is not enough demand on the network to make use of it. Alternatively, during the peak demand hours of early evening the battery would be used to power the house completely.  Effectively, it’d remove the household’s consumption from the grid, thereby reducing demand. At all times the health of the battery is monitored and shown in the Powervault portal, where the amount of charging up, discharging and energy savings can also be seen.

You, as the Powervault battery owner, can leave the grid services contract at any time and will be charged the discount, pro-rated on length of time remaining in the grid services contract. You can read the full terms & conditions here.

Whether you take up grid services or not, you can still make significant energy bill savings by upgrading your solar PV system with the Powervault 3 battery storage, saving your generated power for use later in the day and/or charging on cheap overnight electricity. 

Paying for your solar battery

There are 2 ways to pay for your Powervault 3:

  • In full, prior to installation;
  • You can spread the cost over a longer term with our personal loan option(1).

The personal loan includes:

  • Flexible terms - borrow between £3,000 and £10,000, over one to five years;
  • 6.9% APR representative for loans between £5,000 and £7,499 and 8.9% APR representative for loans between £3,000 and £4,999;
  • Use your loan to cover part or all of the battery cost, additional installation works or other home improvements;
  • Instant decision - we'll tell you straight away if we can offer you a loan;
  • Know what you're paying each month, overpay if you want and there are no set up costs or hidden charges.

As an example, £3,000 over 36 months would be £61.63 per month (8.9% APR representative), total amount repayable would be £3,697.80

Terms and Conditions