Electrical Load Calculator

Estimate connected and demand load, current, generator capacity and monthly energy use. Treat cable and breaker outputs as planning prompts for a licensed electrician.

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Electrical Load Calculation for African Buildings

This calculator totals appliance assumptions and produces a planning estimate. It cannot verify conductor installation conditions, earthing, protective-device coordination, utility requirements or compliance. Have a licensed electrician calculate and test the final installation.

Understanding Total Load vs Demand Load

The total connected load is the sum of all appliance wattages. But not everything runs at once — your iron, kettle, and AC don't typically operate simultaneously. The demand load applies a diversity factor (usually 0.6-0.8 for residential) to give a realistic operating load. This calculator uses this demand load for sizing cables, breakers, and generators.

Generator Sizing for Africa

With unreliable grid power across many African cities, generator sizing is as important as grid sizing. A generator should be rated at least 25% above your demand load to handle motor startup surges (fridges, ACs, pumps). This calculator recommends the minimum generator size in kVA based on your load, accounting for a 0.8 power factor.

Monthly Electricity Cost

The calculator estimates monthly kWh from appliance wattage and daily usage assumptions. Any displayed cost uses a bundled planning rate that may be stale or differ by provider, band, taxes and fees; compare it with a current bill or provider rate before budgeting.

Safety First

Electrical safety is critical in African construction. Common hazards include undersized cables (causing overheating), missing earth connections, lack of circuit breakers, and water exposure. Always hire a licensed electrician and insist on proper testing before energising any installation. Use RCDs (Residual Current Devices) on all socket circuits to protect against electric shock.

Frequently Asked Questions

What size cable do I need for my house?

The calculator's cable output is an illustrative prompt, not a final selection. A licensed electrician must account for installation method, material, temperature, grouping, voltage drop, fault protection and current local rules.

Do I need single phase or three phase?

Use the demand estimate to discuss the supply arrangement with your utility and a licensed electrician. Available capacity and application requirements vary by location and can change.

What is a diversity factor?

Diversity factor accounts for the fact that not all appliances run simultaneously. A 0.7 (70%) factor means you size your supply for 70% of the total connected load. 0.6 is conservative (better for generator sizing), 0.8 is used for offices where more equipment runs continuously.

How do I size a generator for my home?

Take your demand load in kW, divide by 0.8 (power factor), and add 25% for motor starting surges. For example, 5 kW demand ÷ 0.8 = 6.25 kVA × 1.25 = ~8 kVA generator. This calculator does this automatically.

Why does my breaker keep tripping?

Repeated tripping can indicate overload, a fault or another unsafe condition. Do not increase a breaker rating from this estimate; isolate the problem and ask a licensed electrician to inspect and test the circuit.

How much does electricity cost monthly?

Rates vary by provider, tariff band, taxes and time. The tool's bundled rate is an explicit planning assumption, not a current quote; compare the kWh estimate with the current rate on your bill.