What is a kilowatt (kW) vs a kilowatt-hour (kWh)?

The most important thing to remember when it comes to the kW vs kWh difference is that they’re both units of measurement – but they don’t measure the same thing.

A kW (kilowatt) is a measurement of power. It is the rate of electricity an appliance uses – so it’s a useful figure when it comes to understanding how much electricity your household appliances require.

kWh (kilowatt-hours) is a measurement of energy. It measures the total amount of electricity used over a given period of time.

Like driving a vehicle but instead of km and km/h, think of kW as speed and kWh as distance. The higher the speed (kW), the greater the distance you will travel (kWh).

For example, a 1 kW air conditioner running for three hours uses 3 kWh of energy.

Why does the difference matter?

Knowing the difference between kW and kWh can help you understand your electricity bill and identify ways to cut costs. Instead of just looking at the total amount due, check your kWh usage patterns. Are you using more power during peak hours? Could shifting energy-intensive tasks—like running the dishwasher—to off-peak times save you money?

By monitoring kWh usage, you can also compare energy plans and choose the best one for your needs. Flow Home provides smart tools which tracks your real-time electricity use, helping you optimise your consumption.

What is the difference between kilowatts and watts?

Nothing but quantity! A kilowatt is simply 1,000 watts.

When to use kW vs kWh

Understanding the difference between kW and kWh is the first step.

Knowing when to use them, though? That’s next.

Put simply, a kW is useful for understanding how much power each of your household appliances (kettles, coffee machines, food processors, heaters and the like) require to function.

Use this figure when you’re choosing which appliances to purchase – the lower the kW is, the less power that device will use.

The kWh is a measure of how much electricity you’ve actually used. It’s the number your electricity provider uses on your monthly bill.

How do you convert kW to kWh?

Fortunately, the equation to get from kW to kWh is a simple one. You just need time – kW x hours used.

Say you cool your home in summer with a 1 kW air conditioning unit and you leave it whirring away for three hours one hot afternoon. It’s used 3 kWh of power. If it’s been in action for five hours, it’s used 5 kWh of power. And so on!

What factors affect how many kWh a home uses?

There are several factors that impact your home’s kWh usage. These include:

Household size: it’s simple maths – bigger families use more power. More kids mean more hours of TV and video games, more rooms with lights on, and more showers using all the hot water. More energy

Property size: heating accounts for the majority of power consumption. So it figures that the larger your home – that is, the more space you have to keep warm – the more energy you’ll use.

Your living habits: working from home, regularly entertaining guests and taking long showers can all increase your electricity use (and bill!).

The time of year: power bills in Australia tend to go up in summer (air conditioning) and at the height of winter (heating). Bills rise at Christmas, too – when more time spent at home, cooking for longer, and the sparkle of festive lights all swell energy expenditure.

What is the kW usage for common home items?

The amount of electricity common home items use depends on their size, cost and brand – among other factors.

But as a general rule, here are the typical kW usages for your everyday household appliances:

Blender: 0.5 kW

Toaster: 0.85 kW

Microwave: 1 kW

Vacuum: 1 kW

Hairdryer: 1.5 kW

Dishwasher: 1.5 kW

Dryer: 3 kW

Central air conditioner: 3.8 kW

Electric water heater: 4.5 kW

Slow trickle EV charger: 2 kW

Fast EV charger: 7-22 kW