Saving electricity with a home energy monitor？

A home energy monitor is an easy way to see how much electricity you’re using - as you use it - and what it costs. People who fit home energy monitors often find their energy use drops by five to 15 per cent in the first year of using them.
A home energy monitor is an electronic device that helps you see how much electricity you are using at a given time. It is also known as a 'real time display' or 'RTD'.
A clip from the monitor is attached to the cable from your electricity meter. The current is then measured and transmitted wirelessly to a display that you can keep anywhere in your house.
A monitor isn’t a substitute for your electricity bill. However, it can provide a good indication of how much your electricity is costing if you update the monitor with any changes to your tariff.