Battery Sizing: Three Worked Examples
Three real published installations with 5 kWh, 10 kWh and 20 kWh batteries, and the reasoning that put a different size on each roof.
6 Sept 2026
ReadIntermediate
Solar Wiki
Batteries
Home battery storage, chemistries, sizing, and real-world payback.
4 articles in this section.
Articles in Batteries
Batteries Batteries AC Coupled and DC Coupled Batteries Compared
The two ways a home battery can be wired to your solar, what changes for efficiency and cost, and which one fits a new install or a retrofit.
6 Sept 2026ReadIntermediateBatteries Usable Versus Nominal Battery Capacity
A 5.76 kWh battery does not give you 5.76 kWh. Depth of discharge, round trip efficiency and backup reserve explained with figures from the batteries we fit.
6 Sept 2026ReadIntermediateBatteries Where can a home battery go? Siting and safety rules
What PAS 63100:2024 and MCS MIS 3012 say about where a home battery can and cannot be fitted, and how we pick the spot at survey.
6 Sept 2026ReadIntermediate
Other sections of the wiki
- Getting StartedNew to solar? Start here for the basics.
- Solar PanelsPanel types, sizing, efficiency, and what actually matters.
- InvertersString vs micro, hybrid options, and common failure points.
- UK Rules & DNOsG98/G99, export limits, planning permission, and DNO applications.
- Smart Meters & ExportSMETS1 vs SMETS2, export MPAN, and how payments actually work.
- Tariffs & FiT / SEGFeed-in Tariff legacy, SEG rates, Octopus Flux, Agile, and more.
- TroubleshootingCommon problems, fault codes, and when to call an installer.
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