No more batteries,no more chargers and no more wires.This is the future promised by "wireless power".a means of broadcasting electricity through the air to laptops,iPods and other gadgets without the need for cables and sockets . Wireless lighting,audio speakers and digital picture frames are expected to be among the first commercial products exhibited in Las Vegas this week at the International Consumer Electronics Show,the world's biggest gadgets tradeshow. Experts believe this is just the beginning and that eventually wireless electricity could do for battery life what WiFi did for,the Internet.In a world without wires,laptop users in cafes and airport terminals would be inside an "electricity hotspot" and no longer have to delve an awkwardly located socket. "You'd be able to buy.a desk that charged any gadget placed on it, or power any PC you put on top," said James Holland,editor of gadgets website Eleetricpig.co.uk."If each room had wireless power,you'd know that once you walked through the front door your nmbile would start charging up--even while still in your bag or pocket.You'd never need to hunt for the right charger again." Among the companies showcasing the ambitions technology at CES is Power Beam.Its system turns electricity into an invisible laser, then beams it as heat,across the room to a solar cell that conveys it back into dectricity. David Graham,the co-founder of Power Beam,said:"We're going to delete the word 'recharge' from the English dictionary.If your,cell phone is recharging on your desk.all day,you won't be thinking about.it." The Silicon Valley company can currently use a laser to generate about 1.5 watts of power to _ a solar.cell 10 meters away.This, sould be enough to power an electronic speaker or small LED lights,but not enough to operate a laptop,which requires about 30 to 50 watts.However,Graham said that the technology could comfortably be scaled up . Power Beam insists its laser does not lead to a risk to users' health because it is simply moving heat from one place... Which of the following statements is TRUE? A) The laser does harm to people's health. B) The gadgets like audio speakers have been shown at the International Consumer Electronics Show this week. C) The word 'recharge' has been deleted from the English dictionary. D) The technology Can also save energy because it would not work when unnecessary.
D