Boston’s Charles River is the early-morning training ground for at least three collegiate rowing teams and now for one remote-controlled penguin boat. This unusual 12-foot vessel is the first step in using simulated penguin propulsion to bring down the cost, both monetary and environmental, of worldwide shipping. Proteus, as the penguin boat is dubbed, uses rigid flippers instead of propellers. The flippers create less turbulence than propellers, so more of their energy goes into pushing the boat forward. For a given speed, Proteus uses 17 percent less power than a propeller-driven craft of similar dimensions. Proteus’s handler, James Czarnowski, who developed the boat while at mit, says that conversion of even a small fraction of the U.S. shipping fleet to such efficient propulsion would save tens of millions of dollars and hundreds of millions of gallons of fuel annually. Czarnowski must overcome just one difficulty before he can develop a full-size 140-foot test boat. He must develop a steering mechanism. He doesn’t see this as a difficult task. With a little tinkering, he says, the flippers could also serve as rudders.