translation.en: It got about 50 percent of the efficiency -- by the way, that's still a couple thousand times more efficient than a battery would be, to do the same thing.
translation.zh: 点亮了一盏六十瓦的电灯炮 他们计算出的能源效率大约是50% 事实上，这种利用能源的方式 比电池要高出成百上千倍