Skip to main content

What is the difference between kw and kva?

Interested in hiring a generator for your business? You might have come across the term ‘kVA’. Not something widely used outside of this industry, kVA expresses power in the same way that kilowatts do, but we’ll highlight the main differences between kVA vs kW and how to convert between them, below.

What is the difference between kVA and kW in generators?

So, what is the difference between kVA and kW in generators? We’ll talk you through the differentiating factors such as apparent and actual power in more detail below. 

kVA explained

A measure of apparent power, kVA, or kilo-volt-amperes, reads the complete amount of power that is being used in a system, such as a generator. When such a system is 100% efficient, kW, or kilowatts, are equal to kVA. That being said, electrical systems are never working at 100% efficiency, meaning that only some of the apparent power is being converted into working output. Where one kVA is equivalent to 1,000 volt amps, a volt measures electrical pressure, and an amp measures electrical current. 

kW explained

A much more common unit of measurement for the majority of other electrical appliances, such as general household items, a kW is the level of actual power belonging to an electrical system. Also known as working power, a kW is the amount of power that does valid work. 

Converting kVA to kW and back

Need to know how to convert kVA to kW? And vice versa? Firstly, you’ll need to find out what the efficiency, or power factor, is of the system. Measured on a scale of 0 to 1, the average generator has a power factor of 0.8. So to find out the generator size you’ll need for your business, use one of the two converting formulas below:

The converting formula for kW to kVA

  • kW / pf = kVA – for example, 300 kW / 0.8 pf = 375 kVA

The converting formula for kVA to kW

  • kVA x pf = kW – for example, 375 kVA x 0.8 = 300 kW

Enquire about our range of kVA generators for hire at Aggreko

Now you know the difference between kVA vs kW, explore the range of power generators for hire from Aggreko. And if you require further help with knowing what size you need, our team of experts will be happy to assist. Contact us today for more information.