What battery size do I need for load shedding in South Africa?

For Stage 4 load shedding (9 hours/day) with typical essential loads (fridge, lights, TV, router, alarm), you need approximately 3–5 kWh of usable battery capacity. With LiFePO4 at 90% DoD, this means a 3.5–6 kWh battery bank. Most South African installers recommend 5–10 kWh to handle Stage 6 scenarios and allow buffer. Enter your specific loads in the calculator for a precise recommendation.

How many solar panels do I need for load shedding?

To recharge a 5 kWh battery daily in Johannesburg (5.5 peak sun hours), you need approximately 1.5–2 kW of solar panels (4–5 x 400W panels) as a minimum. For Stage 6 reliability and to also power daytime loads directly, 3–5 kW (8–13 x 400W panels) is recommended. More solar means faster battery recharging between outages and less grid dependency.

What inverter size do I need for load shedding?

A 3 kVA inverter handles most essential loads (fridge, lights, TV, router, laptop). A 5 kVA is recommended for comfortable operation with a fridge plus electronics plus fans. A 8 kVA is needed if you want to run a washing machine, additional appliances, or have a larger home. Always size for surge current — a fridge needs 3x its running watts on startup, so a 150W fridge needs 450W of surge capacity.

Is load shedding getting better or worse in South Africa?

Load shedding has eased significantly in 2024–2026 as new generation capacity came online (Karpowerships, gas turbines, and improved coal fleet maintenance). However, Eskom's structural issues remain, and load shedding could return at higher stages during winter or maintenance periods. Solar and battery backup remains a sound investment for energy independence regardless of the current load shedding intensity.

Load Shedding Calculator South Africa

Select your load shedding stage, enter essential loads — instantly get the battery size, inverter rating, and solar panels you need to survive any stage.

Load shedding settings

Load shedding stage?

Battery type?

Essential loads during outage

Appliance	Watts	Qty	Hrs/day	Wh
LED lights				320
Refrigerator				1 350
TV (LED)				320
Laptop / PC				480
WiFi router				135
Ceiling fan				900
Electric gate motor				50
Alarm / CCTV				270

Include solar panels for recharging??

Load shedding system recommendation

4,3 kWh battery capacity needed

Outage load per day3,83 kWh (3 825 Wh)

Battery capacity (gross, at 90% DoD)4,3 kWh

Battery sizing options1x 100Ah or 1x 200Ah (48V)

Inverter / charger size3 kVA minimum

Solar to recharge battery1,1 kW (3x 400W panels)

Outage hours (Stage 4)9 hrs/day

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How to Use This Calculator

Select your load shedding stage

Choose the load shedding stage you want to prepare for. Stage 2 (4 hrs/day) is a minimum baseline. Stage 4 (8–10 hrs/day) has been the most common stage in recent years and is the recommended planning level. Stage 6 (12–16 hrs/day) represents worst-case Eskom scenarios. The stage affects how many hours per day your essential loads must run on battery.

Edit your essential loads

The appliance table shows typical South African household essentials. Edit watts, quantity, and daily hours for each item. Only include loads you need during an outage — not your electric stove or geyser (unless you have solar-powered versions). Focus on: refrigerator, lights, alarm, router, TV, and laptop.

Choose battery chemistry

LiFePO4 (lithium iron phosphate) is strongly recommended. At 90% usable depth of discharge (DoD), you get nearly all the rated capacity. A 10 kWh LiFePO4 gives you 9 kWh usable. Lead acid/AGM is cheaper upfront but only gives 50% DoD — a 10 kWh lead acid bank gives only 5 kWh usable. LiFePO4 also lasts 3,000–6,000 cycles versus 300–500 cycles for lead acid.

Solar panel sizing

Enabling the solar option calculates panels needed to recharge your battery between outages each day, using an average of 4.5 peak sun hours for South Africa (higher in Johannesburg/Pretoria at 5.5 hrs, lower in Cape Town winter at 4.0 hrs). Without solar, you rely on Eskom to recharge your battery — at Stage 6, the grid may not provide enough time to fully recharge.

The Formula

Daily outage load (Wh) = Sum of (Watts × Qty × min(Hours, Outage hours)) Battery capacity (gross kWh) = Daily outage load (kWh) ÷ DoD LiFePO4 DoD = 90% | Lead acid DoD = 50% | Gel DoD = 60% Battery bank (Ah at 48V) = Gross kWh × 1000 ÷ 48V Inverter size = (Peak watts × 1.25) rounded up to standard kVA Note: Fridge uses 3x surge on startup — included in peak calculation Solar panels = Battery kWh ÷ (4.5 PSH × 0.85 efficiency) ÷ 0.4 kW/panel

The 48V system voltage is the standard for South African residential inverters (Victron, Sunsynk, Deye, SolarEdge). Some smaller systems use 24V but 48V is recommended for any system above 3 kWh to reduce current and cable losses.

Example: Stage 4 Home Essentials

3-bedroom Johannesburg home, Stage 4 (9 hrs/day outage), LiFePO4

LED lights (8x 10W, 4 hrs)320 Wh

Fridge (150W, 9 hrs)1,350 Wh

WiFi router (15W, 9 hrs)135 Wh

TV (80W, 4 hrs)320 Wh

2x Laptop (60W, 4 hrs)480 Wh

Alarm/CCTV (30W, 9 hrs)270 Wh

Total daily outage load2,875 Wh

Result

Battery capacity needed (gross)2.875 kWh ÷ 0.90 = 3.2 kWh

Practical battery5 kWh LiFePO4 (recommended size)

Inverter3 kVA minimum (5 kVA recommended)

Solar to recharge~1.0 kW (3x 400W panels)

A 5 kWh LiFePO4 battery, 5 kVA inverter/charger, and 3 x 400W solar panels is a common Johannesburg load-shedding solution in 2026. Installed cost: approximately R60,000–R85,000. This setup handles Stage 6 comfortably for essential loads and recharges fully between outages.

Popular South African Inverter Brands 2026

Most South African solar installers work with these inverter/charger brands:

Sunsynk / Deye: Most popular in SA — affordable hybrid inverters 3.6 kW–12 kW. Good local support.
Victron Energy: Premium quality, highly flexible, best monitoring. MultiPlus-II is the reference standard.
Growatt: Good value hybrid inverters, popular for smaller systems (3–5 kW).
Solis: Reliable midrange option, good for residential string systems.
Goodwe: Budget-friendly with good app monitoring. Popular for grid-tie with battery backup.

For Stage 6 resilience, a hybrid inverter/charger (also called an off-grid or ESS inverter) is essential — it can run on solar, battery, and grid simultaneously, and seamlessly switches between them when load shedding starts. A pure string inverter without battery capability is not suitable for load shedding backup.

FAQ

What size battery do I need for Stage 4 load shedding? ▼

For a typical South African home with essential loads only (fridge, lights, router, TV, alarm) during 9 hours of Stage 4, you need about 2.5–4 kWh of usable battery capacity. With a LiFePO4 battery at 90% DoD, this means a 3–5 kWh battery. Most installers recommend 5–10 kWh to handle two consecutive outages and some buffer for appliance surges.

How much does a load shedding solar system cost in South Africa? ▼

Approximate 2026 prices in ZAR for installed systems: Basic battery backup only (5 kVA inverter + 5 kWh LiFePO4): R45,000–R60,000. Full solar + battery system (5 kVA + 10 kWh + 4 kW solar): R90,000–R130,000. Premium system (8 kVA + 20 kWh + 8 kW solar): R180,000–R250,000. Get 3+ quotes from SAPVIA-registered installers. Prices have dropped significantly with increased competition.

Can I run a geyser and stove on a load shedding system? ▼

Running a 3 kW electric geyser and electric stove during load shedding dramatically increases battery and inverter requirements. A geyser running for 1 hour uses 3 kWh — nearly a full battery cycle for essential loads. Most economical approach: switch to a gas hob for cooking and install a solar geyser or heat pump water heater to eliminate the electricity load. This also makes your solar system much more cost-effective.

LiFePO4 vs lead acid for South African load shedding? ▼

LiFePO4 is the clear winner for load shedding applications: 90% DoD vs 50% for lead acid means you need 40% fewer kWh of battery for the same usable capacity. LiFePO4 lasts 3,000–6,000 deep cycles vs 300–500 for lead acid — a Stage 4 environment with 2 cycles/day means lead acid wears out in 5 months, LiFePO4 lasts 4–8 years. Despite higher upfront cost, LiFePO4 has lower total cost of ownership and is the only practical choice for daily load shedding cycling.