energy

A strange legacy of the Japanese power system’s infancy in the late 1800s is complicating efforts to keep Tokyo supplied with electricity. The problem, as explained by IDG News Service’s Martyn Williams, is that half of the country uses power whose current alternates at 60 Hz, while the other half g

LAS VEGAS — Put this tubular object in your backpack, and you can generate juice for your cellphone — just by walking around. The nPower PEG (short for “personal energy generator”) contains a weight, a spring, some inductive coils and a battery. Put it in your pocket or your backpack, and it wiggles