Choosing the right generator is about more than just picking a size — it’s about making sure your power solution is reliable, efficient, and suited to your specific application.
Start by calculating your power requirements. Consider both the running load (kVA/kW needed to operate equipment continuously) and any higher starting loads required for machinery with motors or compressors. Under sizing can cause overloads and downtime, while oversizing can lead to unnecessary fuel costs.
Next, think about the environment and location. Will the generator be used on a construction site, for backup power at a business, or in a remote area? Factors such as noise restrictions, emissions standards (Stage V compliance), and available space all play a role in selecting the right unit.
Fuel type is another key consideration. Many modern generators are compatible with HVO (Hydrotreated Vegetable Oil) fuel, offering a more sustainable alternative to traditional diesel without compromising performance.
You’ll also need to assess distribution requirements — cabling, load banks, lighting towers, and changeover panels may all form part of your temporary power setup.
Finally, consider support and response times. A reliable supplier offering 24/7 backup, nationwide coverage, and regular servicing ensures your power stays on when it matters most.
The right generator isn’t just about power — it’s about peace of mind.
Check out our power calculator (link to the power calculator)
kVA vs kW Explained
When sizing a generator, understanding the difference between kVA and kW is essential.
What is kW?
kW (kilowatts) is the amount of real power being used to do actual work — for example, running lighting, heating, or equipment.
It’s the power you’re actually paying for and what your machinery truly consumes.
What is kVA?
kVA (kilovolt-amperes) is the apparent power — the total power supplied by the generator.
It includes both:
Real power (kW)
Reactive power (the extra energy needed to create magnetic fields in motors, transformers, etc.)
Generators are typically rated in kVA, because they must supply both real and reactive power.
The Key Difference: Power Factor
The relationship between kVA and kW depends on something called power factor (PF).
Formula:
kW = kVA × Power Factor
Most generators are rated at a 0.8 power factor.
So for example:
100 kVA × 0.8 = 80 kW
200 kVA × 0.8 = 160 kW
This means a 100 kVA generator will usually deliver 80 kW of usable power.
Why It Matters When Choosing a Generator
If you size a generator based only on kW without considering kVA (and power factor), you could overload the machine.
Resistive loads (heaters, filament lighting) are close to 1.0 PF
Inductive loads (motors, compressors, pumps) usually have a lower PF and require more kVA
That’s why generators are specified in kVA — it ensures they can handle the total electrical demand.
Simple Rule of Thumb
If you're unsure:
Multiply kVA by 0.8 to estimate kW output.
Understanding this difference helps you choose a generator that runs efficiently, avoids overloads, and keeps your site powered without issues.