A home battery can store spare solar electricity, charge during a lower-price tariff period or maintain selected circuits during a power cut. The design needs enough usable capacity and power for the intended operation, together with suitable controls, grid connection and installation location.
Home battery storage guide
The guide explains usable capacity, power, location, grid connection, controls and backup as parts of one battery system.
Home battery storage guide →A protected backup reserve is not available for daily tariff cycling. Charging from the grid can also leave less capacity for the next period of solar generation, so the control priorities and reserve need to be stated in the design.
The battery charges from generation that would otherwise be exported, then supplies later household demand. Solar timing, usable capacity, charge power and the export alternative all affect the result.
Solar self-consumption strategy →The battery charges during an allowed lower-price period and discharges when import would cost more. The available window, conversion loss, household load and tariff rules belong in the calculation.
Time-of-use battery operation →Backup needs suitable switching, earthing, protection and a defined load schedule. Stored energy on its own does not make a grid-connected installation operate in island mode.
Whole-home backup changeover →Usable kWh describes the energy available for a stated purpose. Continuous kW describes how quickly the system can charge or discharge. Reserve and conversion loss change what reaches the home.
Compare capacity and power →Usable capacity in kWh is the relevant energy figure. An unexplained nameplate figure may use a different boundary, and any permanent backup reserve reduces the capacity available to normal solar or tariff operation.
Usable battery capacity →Continuous charge and discharge power in kW determine whether the system can fill during the available window and cover the household loads running together.
Battery power rating →Battery, inverter and standby losses sit between charging energy and electricity later supplied to AC loads. The boundary of an efficiency figure matters when systems are compared.
Round-trip efficiency →Metering, CT (current transformer) placement, reserve, schedules, solar priority and export settings decide how the hardware behaves. Loss of a tariff feed or internet connection also needs a known result.
Handover settings and controls →An AC-coupled battery has a separate battery inverter. A DC-coupled battery shares a compatible hybrid-inverter path with solar. The choice affects conversion paths, retrofit work, equipment compatibility and the AC capacity assessed for the grid connection.
Battery siting has to account for escape routes, fire risk, ventilation, flooding, accidental impact, structural support and safe access for installation and maintenance. Product dimensions and enclosure rating do not cover the building, surrounding construction or access.
The site assessment should apply MIS 3012, the IET Code of Practice, PAS 63100, BS 7671 and the manufacturer's instructions. It records the battery position and any preparatory work that location requires.
Location checks
Battery guides
The guides separate the battery’s technical limits from the operating and backup jobs it may be asked to perform.
Installation
Capacity, power, architecture, location, DNO (distribution network operator) connection, commissioning and handover.
Read the guide →Buying
Compare usable energy, charge and discharge power, compatibility, warranty, monitoring and support.
Read the guide →Operation
Set grid charging around household demand, solar headroom, reserve, power limits and export terms.
Read the guide →Backup
Backed-up circuits, changeover, island-mode protection, power, reserve, PV continuation and testing.
Read the guide →Battery Knowledge Base
These entries cover the main definitions, standards and grid-connection boundaries used in battery design.
All battery reference entries →Current official information
Use the current source for the applicable standard edition, installer status, DNO process and any effect on an existing FIT installation.