This link leads you to a very useful device. It will help you understand just how much power is consumed by your electronic devices and appliances. For example, I use mine on chargers to help me remember to unplug them whenever I am not charging a battery. The wattage indicator button is a quick reminder as to how much devices consume electricity every day – day in and day out adding to your electrical bill!
The meter simply plugs in between your appliance and the wall outlet to measure consumption. Once you have figured out usage on one device, move it to the next and so on. By doing this, you will have a better understanding of your energy consumption, and can take easy steps to increase your energy-efficiency.
