Maximising battery storage by charging at cheap rates from the grid
Battery Storage Guide With the right battery storage system, it's possible for a household to store enough electricity to supply the full demand of the property.
Automatic discount £5k+ vat spend: 3%
Automatic discount £10k+ vat spend: 4%
Automatic discount £15k+ vat spend: 5%
| Battery system | Availability | Type | On or Off grid | Multiple chargers | IP rating |
Charge/ Discharge rate |
Maximum Capacity | Typical Battery cost/kWh +vat | Typical Kit cost/kWh +vat | Depth of Discharge |
| GSL All In One 5.5kw Hybrid 20.48kwh | Good | Floor mounted | On & Off grid | No | 55 | 5kWh | 40.96kWh | £240 | £281 | 90% |
| Sunsynk 3.6kw Hybrid / GSL 20.48kwh | Good | Floor mounted | On & Off grid | Yes | 55 | 3.6kWh | 40.96kWh | £240 | £308 | 90% |
| Sunsynk 5kw Hybrid / GSL 20.48kwh | Good | Floor mounted | On & Off grid | Yes | 55 | 5kWh | 40.96kWh | £240 | £333 | 90% |
| Sunsynk 8kw Hybrid / GSL 20.48kwh | Good | Floor mounted | On & Off grid | Yes | 55 | 8.8kWh | 40.96kWh | £240 | £397 | 90% |
| Sunsynk 5kw Hybrid / Sunsynk 5.1 20.48kwh | Good | Stackable | On & Off grid | Yes | 55 | 5kWh | 163kWh | £238 | £300 | 95% |
| Sunsynk 5kw Hybrid / Sunsynk BYD 21.36kwh | Good | Stackable | On & Off grid | Yes | 55 | 5kWh | 76.8kWh | £292 | £339 | 100% |
| Solis 3kw RAI / Pylontech 19.2kwh | Good | Stackable | On grid | No | 55 | 3.3kWh | 29kWh | £236 | £274 | 95% |
| Solis 6kw Hybrid / Pylontech 19.2kwh | Good | Stackable | On grid | No | 55 | 5kWh | 29kWh | £236 | £301 | 95% |
| Givenergy 6kw AC All In One 13.5kwh | Good | wall or floor mounted | On & Off grid | No | 65 | 6kWh | 81kWh | £411 | £411 | 100% |
| Givenergy 5kw Hybrid Gen3 19kwh | Good | wall or floor mounted | On grid | No | 65 | 3.6kWh | 47.5kWh | £275 | £357 | 100% |
| Givenergy 3kw AC 19kwh | Good | wall or floor mounted | On grid | No | 65 | 2.5kWh | 47.5kWh | £275 | £330 | 100% |
| Libbi All In One 5kw Hybrid 20kwh | Pre-order | All In One | On grid | No | 65 | 5kWh | 20kWh | £512 | £613 | 90% |
| Alpha Smile B3 Plus AC 20kwh | Good | All In One | On grid | No | 65 | 3kWh | 30kWh | £341 | £387 | 95% |
| Alpha Smile 5 5kw Hybrid 20kwh | Good | All In One | On grid | No | 65 | 5kWh | 60.1kWh | £335 | £404 | 95% |
| Huawei 5kw Hybrid 20kwh | Good | wall or floor mounted | On grid | No | 66 | 5kWh | 30kWh | £559 | £611 | 100% |
| Fox HV Cube 5kw Hybrid 20.16kwh | Good | Stackable | On grid | No | 65 | 5kWh | 28.21kWh | £273 | £319 | 90% |
| Fox HV Cube 5kw AC 18.64kwh | Good | Stackable | On grid | Yes | 65 | 5kWh | 28.21kWh | £295 | £332 | 90% |
| Fox HV2600 5kw AC 18.2kwh | Good | Stackable | On grid | No | 55 | 5kWh | 18.2kWh | £333 | £312 | 90% |
| SolaX 5kw Hybrid 17.4kwh | Good | wall or floor mounted | On grid | Yes | 55 | 6kWh | 17.4kWh | £312 | £394 | 90% |
| SolaX 3.6kw AC 17.4kwh | Good | wall or floor mounted | On grid | Yes | 55 | 5kWh | 17.4kWh | £338 | £364 | 90% |
Sizing & selecting which battery storage system is right for you
Two key factors to take into consideration when selecting the battery storage system are the storage capacity and your peak demand.
The advisable storage capacity can be calculated by looking at your average usage over a 24hr period, and determining how much of this amount you wish to be able store. If you don't have a smart meter this can be found on your electric bills or by contacting your supplier. Over-sizing will mean that more capital will be invested than required, but can allow for increased usage in the future. Under-sizing usually results in lost potential savings, but maximises the capital invested.
If you have solar pv then you need to look at how much spare electricity you are generating during the day time that can be stored and how much of this is worthwhile storing to for after daylight hours. This can also be combined with how much you want to charge at night time from the grid to top up the batteries.
Peak demand is the maximum electricity demand at any given time of the day. It is important to know your peak demand to ensure the system you go with will meet either all or most of your demand. A system that cannot supply this demand may mean you still need to draw significant amounts of electricity from the grid during costly peak-rate hours. For example, if you regularly have 5kW of high demand appliances running, and you only have a battery system that can discharge at 2.5kWh, you will still require 2.5kWh from the grid. Whereas If you have a system that can discharge at 5kWh then you will meet your peak demand without needing to draw from the grid.