Most of us passively allow phantom power to haunt our homes. These “power vampires” consume electricity, pollute the atmosphere, and drain our wallets even after we have turned off all the switches. They come in the guise of useful digital clock displays, handy gadget chargers, and shiny status lights around your house. They consume power 24 hours of the day, 365 days of the year. According to the International Energy Agency (IEA) estimates, global energy consumption due to standby power, as it is called, is between 200-400 terawatts per year.
 Single-Most Wasteful Use of Energy
It has been estimated that about 10 percent of total home energy use is due to appliances and electronic equipment in standby mode. When devices, from computers and televisions to clock radios and cell phone chargers, are plugged in but not ‘on’, they leech power and become the single-most wasteful use of energy. This form of use of energy by electronics items is known as phantom power.
We've got so used to the instant-on standby mode, that we don’t realize how much this convenience is costing us. A simple home test found a remote-controlled fan was using around 15 watts just waiting to be on. Phantom load costs US consumers more than $4billion per year and many billions of kilowatt-hours. Each American home carries phantom load from 1.5 to 4 kilowatt-hours per day, or several dollars per month.
Most electronics products come with phantom loads. If your device has LED lights or a digital clock, if it works with a remote control or soft-touch keypad, or has a quick-start mode, then chances are it's suckling power 24 hours a day, year round. Even if portable devices remain plugged into the wall after reaching full charge, they can also become phantom loads.
Features that require standby power are:
• internal clocks and sensors;
• external clock displays and panel display LEDs;
• remote control sensors;
• battery rechargers and power-conversion packs;
• communications between a base unit and a portable unit (as in a portable phone).
You can find out when an appliance is still drawing power when it’s in the “off” state (but still turned on at the power point)
• When the appliance is in remote control, it still uses power while it waits to detect you switching it on with the remote.
• A clock, or a “standby” light, will be using power (at the very least to display the clock or light)
• If the appliance is warm to the touch when switched off, it is often due to some sort of electric current. Those power adapters which you use to charge up your mobile phone are a good example.
 Home Electronics
Home electronics alone are reported to account for 15 per cent to 20 per cent of household electricity. During the lifetime of a household satellite dish, digital cable receiver, or DVD player more than 75 per cent of power is consumed in standby mode.
Electronic devices can consume 5 to 8 watts each even when "off". A home entertainment system's components can consume as much as 30 watts even when off. At 24 hours a day that translates into 720 watt hours (30 x 24) of energy used to do nothing. For a system where the charging source may produce 2500 watthours of power in a day, this amounts to a significant chunk of your available energy.
 Simply Switching-Off Doesn’t Help
How to pull the plug on phantom load? Simply shutting down your computer when you're away from your home or office will not suffice. What is required is having your computer, printer and other electronic gadgets plugged into a power bar and turning that bar off when not in use. This will prevent standby power from surging through the wires. Refer to Power Strips Save Energy 
Research indicates that only 5% of the power drawn by cell phone chargers is actually used to charge phones. The other 95% is wasted when you leave it plugged into the wall, but not into your phone.
 Some Remedial Measures
To get details on how to measure the exact amount of electricity something uses, refer to How do I find out how much electricity something uses? 
You can buy a Kill-a-Watt Electricity Usage Monitor  . This device tells you how much electricity something uses, either at a given moment or over an extended period of time. Just plug the device into the meter, plug the meter into the wall, and read the display.
• Buy energy-efficient appliances. They may initially cost a little more, but in the long run you will end up saving money
• Unplug your iPod, cell phone, laptop, digital camera or any other gadget that requires an internal or external battery to be recharged, as soon as it is fully charged
• Avoid the practice of leaving your cell phones plugged in before bedtime
• Replace old, heavy battery chargers with one designed to save energy.
Also see Philips GS4T6FO 4-Outlet Household Surge Protector with LCD Timer  to calculate an item's electrical cost by the day or week.
 All Not Wasted Power
All vampire power, however, is not wasted. Modern electronics incorporate many features for which standby power is critical for proper functioning. An Australian study has found that it is possible to reduce vampire power by 30 percent by using better technologies, without adding any cost to the end consumer.
There is a move by the British government to outlaw standby switches on televisions and video and DVD players Measures are to be taken to make refrigerators, washing machines and dishwashers energy-efficient. Light bulbs that burn too much energy will be phased out.