How to Size and Choose a Generator in Kenya

Power cuts are a fact of doing business in Kenya, and a generator that is too small trips the moment a motor starts, while one that is far too large wastes fuel running lightly loaded. Sizing it properly takes four steps.

1. List everything the generator must run

Walk through the premises and write down every load you need during an outage — lights, computers and servers, refrigeration, water pumps, compressors, machines. Note each item's rated power in watts or kilowatts from its nameplate. Be honest about what can be switched off: every kilowatt you drop from the list is capacity you don't pay for.

2. Account for starting current

Electric motors draw several times their running current for a moment when they start. Pumps, compressors, air conditioners and machine tools are the usual culprits. If several motors could start together, the generator must cover that peak, not just the running total. Staggering start-up — or using soft starters and variable-speed drives — keeps the required size down.

3. Convert to kVA and add headroom

Generators are rated in kVA; your loads are mostly in kW. For typical generators, kW ≈ kVA × 0.8, so divide your kW total by 0.8 to get kVA. Then add 20–25% headroom so the set isn't running flat out and you have room for growth. A site needing 16 kW of real power therefore wants roughly a 20 kVA generator, and 25 kVA gives comfortable margin.

• Standby rating — for emergency use during outages; not intended for continuous running.
• Prime rating — for running as the main power source for extended hours, usually lower than the standby figure.

4. Choose the right type

• Diesel or petrol: diesel generators are the standard for businesses — better fuel economy under load, longer engine life and safer fuel storage. Petrol units are cheaper to buy and suit small, occasional loads.
• Single or three-phase: match your supply. Kenyan mains is 240 V single-phase or 415 V three-phase at 50 Hz. Three-phase motors and larger premises need a three-phase set.
• Automatic transfer switch (ATS): starts the generator and switches the load over when the grid fails, then switches back. It also prevents back-feeding power into the grid, which endangers line workers.
• Silent canopy: worth it in offices, hospitals and residential areas.

Running costs and maintenance

Fuel is the largest running cost. A diesel generator uses roughly a quarter of a litre of fuel for each kWh it produces at a healthy load, and efficiency falls away when a large set runs very lightly loaded — another reason not to oversize. Follow the manufacturer's service schedule for oil, filters and coolant, run the set under load regularly, and keep the batteries charged so it starts when you need it.

Getting a quote

Send us your load list, whether you need single or three-phase power, and whether you want automatic changeover. We'll recommend a size and prepare a quotation in Kenya Shillings, with delivery within 0–30 days anywhere in Kenya.