How to reduce your electricity bill with power meters

How much electrical power do your various computing devices consume?

Very few of us can answer that question with any confidence, as we normally come into contact with our energy consumption only in the form of bills – and those give only a total consumption figure for all of a household’s appliances, across a period of months. It’s impossible to tell anything about any particular device.

In fact, your PC probably isn’t the most energy-hungry device in your home – if you have a fridge-freezer or a washer-dryer, that’s likely to cost you more.

But it’s certainly a contributor to your bills, and you could save a good few quid each month by managing your overall power usage. Even if the financial incentives don’t move you, it’s simply good citizenship not to waste energy.

Measuring your consumption

The first step is to find out how much power you’re actually using. As we’ve mentioned, power bills are a very crude source of information.

With the right software, it’s possible to upload your power usage data to online services, where it can be tracked and analysed for you

You can keep much closer tabs on your consumption by investing in a whole-house monitor – an electronic gadget that’s able to track and analyse your power consumption automatically. Look online and you’ll find plenty such devices on offer from less than £30.

You don’t have to be a qualified electrician to install a whole-house monitor. The device comes with a clamp, which you simply fit around your main electricity cable (either at the fuse box or at your electricity meter).

The current flowing through the mains cable induces a secondary current in the clamp, which can then be measured to find out how much power is flowing into your home.

With a whole-house monitor you can program in the amount you pay for electricity and track your consumption in pounds and pence. Many monitors can also track historical usage – so, for example, you can compare your power consumption this weekend with your average over the past year.

Advanced monitors – such as the AlertMe Energy Monitoring Starter Kit and the Current Cost Envi – can transfer detailed usage information to your PC, so you can analyse the data yourself.

For example, you could import the figures into Excel and look for spikes, so you can work out what’s caused your power consumption to rocket.

You can also calculate how much your usage would cost if you moved to a different electricity provider or tariff – a possible way to reduce your electricity bill without lifting a finger.

Online monitoring with Google

With the right software, it’s possible to upload your power usage data to online services, where it can be tracked and analysed for you. A few companies offer such services on a commercial basis, but the most attractive choice is Google’s free PowerMeter service.

Launched in 2009, Google PowerMeter isn’t as well known or ubiquitous as the company’s Gmail or Maps services. That isn’t really a surprise, as it’s useful only to people who are in a position to provide power usage statistics. But if you shop around you can find a PowerMeter-compatible monitor online for less than £40.

And it’s growing in popularity. In the US, there are now nine different manufacturers of home power meters that are compatible with Google PowerMeter.