Environmentally the leds are good news too because they last 20 times longer than conventional light bulbs and are predicted to halve the cost of lighting the office or home by 2025 这种二极管的发明从环保的角度考虑同样也是一件好事,它的使用寿命是传统电灯泡的20倍,预计到2025年能够为家庭与办公照明节省一半的开支。