Once the device is plugged in and ready to go you need to follow the instructions carefully to set information such as the pricing for electricity (which you can get from your electricity bill or possibly your supplier website). This then enables you to not only see what energy is used but how much that is costing you. The option of setting two prices is a good feature if you are on a different rate at different times of day. For more detail on the information you can look at on the device and any teething problems, the FAQ on the energenie website is very useful.
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