City develops charger to cut power wasted by mobile devices• by Luke Nava
A new electrical charger, developed at City University London, could radically reduce the amount of energy and money that is wasted when chargers are left plugged-in but devices are not in use - a problem said to be responsible for 1% of global carbon dioxide emissions*.
The design works with multiple products, such as mobile handsets, laptop computers or MP3 players, to completely eliminate the power losses that occur when chargers are connected to live electrical sockets, but the devices themselves are not attached.
65% of UK mobile phone owners leave their chargers plugged in once a week**, but the redundant adapters continue to use power. With around 70m handsets in the country, conservative estimates suggest that six gigawatt-hours of energy - equivalent to six large power stations working for one hour each - is wasted in this way every year.
While there have been industry and regulatory initiatives in the past to introduce standards for more energy efficient chargers, it is our aspiration to reduce wasted power to zero, helping the environment and enabling consumers to cut their electricity bills.
Sanowar Khan, Professor of Instrumentation and Sensors at City University London
The simple, low cost solution makes use of a micro-switch, which can be embedded in any type of connector between the charger and the device. This prevents the flow of electricity when the end product is not connected, providing both green and cost-saving benefits, as well as the safety advantage that wires do not remain live - something which can be dangerous in the event of a flood or if cable insulation is worn through, for instance.
It has been patented by the University's technology transfer team, the City Research & Enterprise Unit (CREU), which is now seeking to build partnerships with manufacturers of power supplies and consumer electronics to put the idea into production. Potential applications include all portable electrical devices and any appliances with detachable adapters.