What will the electricity miracle be? [Blueprints for a Miracle]

TABLE TENNIS ISN'T meant to be played at Mach 2. At twice the speed of sound, the ping-pong ball punches a hole straight through the paddle. The engineers at TerraPower, a startup that has designed an advanced nuclear power reactor, use a pressurized-air cannon to demonstrate that very point to visitors. The stunt vividly illustrates a key concept in nuclear fission: Small objects traveling at high speed can have a big impact when they hit something seemingly immovable. And perhaps there is a larger point being made here, too-one about a small and fast-moving startup having a big impact on the electric-power industry, which for many years also seemed immovable.