t seems impossible that anything of technological significance could emerge from the basement of Richards Hall, the engineering building of Northeastern University in Boston. It is a haphazard warren, home to discarded office chairs, old lockers, and unclaimed pencils, all covered in a coat of fine gray dust. But it is also the home of the Hydro-Pneumatic Power Laboratory, where a 73-year-old Russian-born mechanical engineering professor named Alexander Gorlov spent a decade redesigning one of the world's oldest and simplest machines, the turbine.
Smiling, Gorlov walks over to a cluttered corner of the lab and wheels out a gurney. Strapped to it is an object that looks remarkably like an oversize beater from an old hand-held mixer. Still, this is it, the Gorlov Helical Turbine, which may someday help turn hydroelectric power into one of the most important and environmentally benign renewable energy sources on the planet. Gorlov's turbine received the 2001 Thomas A. Edison Patent Award, given each year by the American Society of Mechanical Engineers, which hailed its potential "to alleviate the world-wide crisis in energy."
The first thing to understand is that this is not hydropower as we know it. Just as wind turbines harness the kinetic energy of moving air, Gorlov's turbine has been designed to harness the kinetic energy of moving water -- even slow-moving currents -- without the need for dams. Remove dams from the equation and electricity can be generated almost anywhere water flows--in man-made canals, tidal straits, the open ocean, and unimpounded rivers. "Ocean and river currents contain a huge amount of energy," Gorlov says. "The question has always been: How can we get it without destroying the environment?" He is convinced that his turbine provides the answer.
This innovative form of hydropower is so new that its pioneers haven't even settled on a name for it. Some call it free-flow hydropower; others kinetic, low-head, or simply unconventional hydropower. Gorlov's design is one of many jostling for attention and investors. Companies in the United States, the United Kingdom, Norway, and Canada are building and testing their own free-flow turbines, but while the engineering can vary wildly, developers agree that free-flow hydropower has enormous potential.
The amount of power that could be produced from ocean currents almost defies comprehension. The currents flowing through San Francisco's Golden Gate alone, for instance, could produce an estimated 2 gigawatts per day -- more than twice what the city needs at times of peak demand. The global potential is some 3,000 gigawatts, according to the United Kingdom's Department of Trade and Industry. The agency estimates that 3 percent of that total, or 90 gigawatts, is economically recoverable using current technologies.