Petrol vs Diesel Generator: Cost, Fuel Use, Running Hours and Which to Choose
- Petrol: cheaper, occasional use
- Diesel: long hours, efficient
- Size to your load
- Never run indoors
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Generators at H-TECH
DAYLIFF DG1200S 1 kVA Petrol GensetKSh 26,100
DAYLIFF DG3800ST 2.8 kVA Petrol GensetKSh 50,370
DAYLIFF DG7500P 6 kVA Petrol GeneratorKSh 123,980
DAYLIFF DG6000DS 4.5 kVA Diesel Generator with ATSKSh 247,950
DAYLIFF DG Multi-4 Multifunction Power PackKSh 124,990
DAYLIFF Automatic Voltage Switcher 3PKSh 16,310| Product | Price |
|---|---|
| DAYLIFF DG1200S 1 kVA Petrol Genset | KSh 26,100 |
| DAYLIFF DG3800ST 2.8 kVA Petrol Genset | KSh 50,370 |
| DAYLIFF DG7500P 6 kVA Petrol Generator | KSh 123,980 |
| DAYLIFF DG6000DS 4.5 kVA Diesel Generator with ATS | KSh 247,950 |
| DAYLIFF DG Multi-4 Multifunction Power Pack | KSh 124,990 |
| DAYLIFF Automatic Voltage Switcher 3P | KSh 16,310 |
Current listed prices incl. VAT (updated 19 October 2026).
Petrol vs Diesel at a Glance
| Petrol | Diesel | |
|---|---|---|
| Purchase price | Lower | Higher |
| Fuel efficiency | Lower | Higher, especially at steady load |
| Running hours | Short, occasional | Long, frequent |
| Weight and size | Lighter, portable | Heavier |
| Engine life | Shorter | Longer with good maintenance |
| Fuel storage | Petrol is more volatile | Diesel is safer to store |
Which Should You Choose?
- Home with short blackouts: a small petrol genset for lights, TV, fridge and phone charging.
- Shop or kiosk: petrol for occasional outages; diesel if outages are long or frequent.
- Milk ATM, chiller, water plant, clinic: diesel with an automatic transfer switch (ATS) so power switches over by itself (see backup power for dairy and water businesses).
Size It First
Add up the running watts of everything you need at the same time, then allow extra for motors and compressors, which take several times their running power to start. Use our generator size calculator. An undersized generator trips, overheats or damages equipment; a hugely oversized one wastes fuel.
Automatic Transfer Switch (ATS)
An ATS starts the generator and switches the load over when mains fails, then back when it returns. It is essential where nobody is on site at night (chillers, pumps). Protect sensitive machines with an automatic voltage switcher too.
Running Costs
Fuel cost depends on load and hours, not just tank size. Run at a steady, moderate load, service on time (oil, filters, plugs or injectors) and keep a log of hours and fuel. For a water pump, compare with solar: solar pump vs generator cost.
Safety: never run a generator indoors, in a garage or near windows: exhaust carbon monoxide kills. Connect to a building only through a proper changeover or ATS installed by a qualified electrician.
Frequently asked questions
Is a petrol or diesel generator better?
Petrol for occasional short outages and small loads; diesel for long running hours and heavier loads.
Which generator uses less fuel?
Diesel generators are usually more fuel-efficient at steady loads.
What size generator do I need for my house?
Add up the loads you need at the same time plus starting power for motors; see the generator size calculator.
What is an ATS on a generator?
An automatic transfer switch that starts the generator and switches power over when mains fails.
Can I run a generator indoors?
No. Exhaust contains carbon monoxide, which is deadly.