Load shedding
How much battery do I need for Stage 6 load shedding in South Africa?
For typical SA home essentials (lights, Wi-Fi, fridge, selected plugs — roughly 0.5–1.5 kW), plan about 5–15 kWh of usable battery for Stage 6, depending on how many hours you must cover and whether solar can recharge between stages. Convert sticker kWh × DoD before you compare quotes.
Updated 26 October 2026 · Illustrative ranges — not a formal quote or legal advice.
Answer first: Runtime hours ≈ usable kWh ÷ average essential load. A 10 kWh sticker at 90% DoD is ~9 kWh usable; at 1 kW essentials that is ~9 hours before inefficiencies — DoD, runtime tool.
Define essentials ruthlessly
Lights, routers, fridge, alarms, medical devices. Geysers, ovens, pool pumps and EV chargers are usually non-essential during deep stages — split, EV shedding.
Stage 6 patterns
Long evening slots without sun drain storage fastest. Daytime stages hurt less if PV is up — hybrids with NRS-compliant anti-islanding still protect the grid while islanding the house — solar in shedding.
Chemistry
Prefer LFP for home cycling — LFP vs NMC.
Worked bands (illustrative)
| Essential load | Hours to cover | Rough usable kWh |
|---|---|---|
| 0.6 kW | 6 | ~4–5 |
| 1.0 kW | 8 | ~9–11 |
| 1.5 kW | 8 | ~13–16 |
Inverter backup rating
kWh is useless if the hybrid cannot surge the fridge and kettle on the backup port — inverter size.
SA caveats
Shedding schedules change; size with margin. Educational only.
Quick FAQ
Is bigger always better? Diminishing returns if PV cannot refill.
Two smaller packs? Only if inverter supports paralleling.
Generator instead? Possible with ATS — fuel maths vs battery — ATS.
Savings framing for this decision
Metro residential export credits in 2026/27 sit near 108–185 c/kWh incl. VAT (Cape Town ~152.93, City Power 143.29, Tshwane ~108.25, eThekwini ~184.60) while imported kWh often cost several rand. Designs that raise self-consumption beat designs that chase export. Fixed network charges remain after solar — model them. EV households should price home AC charging (often roughly R53–R85 per 100 km at typical residential rates) separately from public DC (often ~R6–R8/kWh, with documented outliers such as SAEV Richmond ~R3.49/kWh vs GridCars ~R7.35 per DriveElectric).
Compliance framing for this decision
Grid-parallel systems need NRS 097-2-1 type-tested inverters, a CoC to SANS 10142, and usually SSEG registration with the distributor (≤100 kW) or NERSA (above). EV wallboxes need dedicated circuits and registered-person commissioning (SANS 10142-1 clause 6.16.8 context in the Ed. 3.3 draft enquiry text). Skipping paperwork to “save time” is how projects stall at the municipal desk or fail insurance scrutiny.
Stage 6 framing for this decision
Size usable battery kWh to essentials (lights, connectivity, fridge, selected plugs) before luxury loads or EV charging on the backup bus. A 5–15 kWh usable LFP band covers many suburban essential scenarios depending on hours and whether PV can recharge between stages. Do not empty the house battery into a car unless the hybrid was deliberately oversized for that behaviour.
Quote hygiene
Require a single-line diagram, labour vs hardware split, NRS certificate PDFs, warranty PDFs, and written SSEG responsibility. Photograph the DB before works. Keep serial numbers and app credentials in one cloud folder. Re-read municipal tariff annexures every July.
Putting the wider desk numbers to work
Four recurring figures: export credits ~108–185 c/kWh incl.; home EV energy often R53–R85/100 km; ~7 kW wallbox all-in often R17k–R35k+; NERSA ≤100 kW distributor path. Use them as sanity checks when a salesperson’s spreadsheet drifts into fantasy. Compare two compliant quotes on the same load profile rather than hunting grey-import bargains without support.
Practical next steps (1)
Write down your tariff code, last 12 months of kWh, main breaker size, and roof photos. Send the same pack to two installers. Ask each to state usable battery kWh, export assumptions, and whether prepaid migration applies. For EV add-ons, confirm load management and CoC line items. Schedule estate approvals before scaffolding. After commissioning, verify monitoring for a full sunny week and one shedding evening. If numbers diverge from the quote model by more than a little, call the installer while retention is still open.
Practical next steps (2)
Write down your tariff code, last 12 months of kWh, main breaker size, and roof photos. Send the same pack to two installers. Ask each to state usable battery kWh, export assumptions, and whether prepaid migration applies. For EV add-ons, confirm load management and CoC line items. Schedule estate approvals before scaffolding. After commissioning, verify monitoring for a full sunny week and one shedding evening. If numbers diverge from the quote model by more than a little, call the installer while retention is still open.
Practical next steps (3)
Write down your tariff code, last 12 months of kWh, main breaker size, and roof photos. Send the same pack to two installers. Ask each to state usable battery kWh, export assumptions, and whether prepaid migration applies. For EV add-ons, confirm load management and CoC line items. Schedule estate approvals before scaffolding. After commissioning, verify monitoring for a full sunny week and one shedding evening. If numbers diverge from the quote model by more than a little, call the installer while retention is still open.
Practical next steps (1)
Write down your tariff code, last 12 months of kWh, main breaker size, and roof photos. Send the same pack to two installers. Ask each to state usable battery kWh, export assumptions, and whether prepaid migration applies. For EV add-ons, confirm load management and CoC line items. Schedule estate approvals before scaffolding. After commissioning, verify monitoring for a full sunny week and one shedding evening. If numbers diverge from the quote model by more than a little, call the installer while retention is still open.
Practical next steps (2)
Write down your tariff code, last 12 months of kWh, main breaker size, and roof photos. Send the same pack to two installers. Ask each to state usable battery kWh, export assumptions, and whether prepaid migration applies. For EV add-ons, confirm load management and CoC line items. Schedule estate approvals before scaffolding. After commissioning, verify monitoring for a full sunny week and one shedding evening. If numbers diverge from the quote model by more than a little, call the installer while retention is still open.
Practical next steps (3)
Write down your tariff code, last 12 months of kWh, main breaker size, and roof photos. Send the same pack to two installers. Ask each to state usable battery kWh, export assumptions, and whether prepaid migration applies. For EV add-ons, confirm load management and CoC line items. Schedule estate approvals before scaffolding. After commissioning, verify monitoring for a full sunny week and one shedding evening. If numbers diverge from the quote model by more than a little, call the installer while retention is still open.