How to measure your electricity use

Woman measuring electricity use on ipad

Knowledge is power, but a little knowledge can help you use a little less power, too. Here’s what you need to know to actively measure and manage your home electricity use and save money on your electricity bills. 

There are two major charges that appear on your electricity bill – a supply charge and a usage charge. 

The supply charge is also called a fixed charge, because it has nothing to do with how much power you use. Even if you switched everything off at home, went on that long holiday you’ve been dreaming of and used absolutely no electricity at all during a given billing period, you’d still have to pay a supply charge, because it’s the amount your energy provider charges you to keep your property connected to the network. 

The usage charge, also called the consumption charge, is where things get interesting. It’s a variable charge, which means it depends on your usage. If you make an effort to be more energy-efficient and use less electricity, you can reduce your usage charge. 

Measuring your energy usage 

If you want to adjust your energy usage to save money on your bill, then it’s good to know where your power is actually going to waste. A home energy monitor can provide you with real-time information about how and when you’re using your power – including kilowatt hour usage, costs and even your carbon dioxide emissions – as well as historical usage data, so you can compare, contrast and make informed decisions. 

Want to know how much power your lights are using, or how much energy your air conditioner is eating up? Just switch the appliance in question on and off, and see how it affects the figures displayed on your energy monitor. 

There are different types of energy monitors available, designed to suit a range of budgets. Generally, it’s much easier to set up and use an energy monitor if you have a ‘smart’ meter that digitally tracks your energy consumption and stores the data, but monitors are available for traditional meters – i.e. the ones a meter reader has to come and manually check – as well. 

Online energy monitors 

Much like your old CD and DVD collection, physical energy monitors are largely becoming redundant thanks to the internet. An online energy monitor can be accessed on a desktop computer or through a mobile app, and if you have a smart meter, you’ll probably already have access to one through your energy retailer. (If you’re not sure how to access it, ask your retailer – their contact details will be on your electricity bills.)

An online energy monitor will display your real-time energy usage data, and also provide you with insights based on your historical energy usage. It can also analyse your usage patterns to help determine which of your devices and appliances are causing your bills to spike. 

Most solar inverters and meters can also be connected to an online energy monitor, so you can track your solar output and efficiency and see how much money your solar array is saving you. 

If you don’t have a smart meter, don’t despair – a qualified electrician should be able to attach a sensor to your traditional meter, which can be read by an attachment added to your internet router.

Wireless energy monitors 

Available for both traditional and smart meters, a wireless electricity monitor is a portable, tablet-like physical device that displays your real-time energy usage data. 

Unfortunately, not all wireless energy monitors display historical usage data, so if you want to track how your energy usage changes over a period of time, you’ll need one of the more expensive models (or an online monitor). Some wireless monitors can also be connected to solar inverters and meters, but they won’t provide the same level of insight as an online monitor. 

No matter which wireless model you choose, or which type of meter you have, you will need a qualified electrician to attach the wireless energy sensors to your meter so you can start getting the data you’re after. 

Ultimately, if you have a traditional meter, whether or not it’s worth the effort and expense required for you to set up an energy monitor will largely depend on how often you think you’re going to use it, and what you plan to do with the insights it gives you. 

Read next: 7 ways to reduce your electricity usage and save on your power bills