In Newcastle, England, there is more riding the waves here than surfers, thanks to a growing number of scientists, engineers and investors. A group of entrepreneurs is harnessing the perpetual motion of the ocean and turning it into a commodity in high demand: energy.
Right now, machines of various shapes and sizes are being tested off shores from the North Sea to the Pacific one may even be coming to the East River in New York State this fall to see how they capture waves and tides and create marine energy.
The industry is still in its infancy, but it is gaining attention, much because of the persistence of marine energy inventors, like Dean R. Corren, who have doggedly lugged their wave and tidal prototypes around the world, even during the years when money and interest dried up. Mr. Corren, trim and cerebral, is a scientist who has long advocated green energy and pushed through numerous conservation measures when he was chairman of the public energy utility for the city of Burlington, Vt.
Another believer in the technology is Max Carcas, head of business development for Ocean Power Delivery of Edinburgh. In the long run, this could become one of the most competitive sources of energy, said Mr. Carcas.
His company manufactures the Pelamis, a snakelike wave energy machine the size of a passenger train, which generates energy by absorbing waves as they undulate on the ocean surface.
With high oil prices, dwindling fuel supplies and a growing pressure to reduce global warming, governments and utilities have high hopes for tidal energy. The challenge now is turning an accumulation of research into a viable commercial enterprise, which for many years has proved elusive.
No one contends that generating energy from the oceans is a preposterous idea. After all, the fuel is free and sustainable, and the process does not generate pollution or emissions.
Moreover, it is not just oceans that could be tapped; the regular flow of tides in bodies of water linked to oceans, like the East River, hold promise too. In fact, it seemed like such a sensible idea that inventors started making the first wave of such generators centuries ago. Many operated like dams, trapping water and then releasing it after the tides fell. But they were outmoded with the rise of steam engines and other more efficient fuel sources.
Ocean energy had a brief revival when oil prices rose in the 1970s, and prototypes were tested in Europe and China. But financing dried up when oil prices were low in the 1990s, and advances in wind turbines and other renewable energy elbowed out tidal projects.
These days, wave power designs vary from machines that look like corks bobbing in the ocean to devices that resemble snakes pointing into waves. There are shoreline machines that cling, like limpets, to rocks.
Tidal power machines, in contrast, often come in the form of turbines, which look like underwater windmills, and generate energy by spinning as tides move in and out; some inventors also are testing concrete-and-steel machines that lie on the seabed and pipe pressurized water back to the shore.
Even big commercial power companies are joining the action. General Electric; Norsk Hydro, a Norwegian company; and the Germany power giant Eon have recently pledged money for new projects or investments in tiny marine energy companies.
It is an untapped renewable energy source, said Mark Huang, senior vice president for technology finance in General Electrics media and communications business, which is financing marine projects. There is no where to go but up, Mr. Huang said. He added that solar or wind energy should be viewed as a case study for the direction marine energy could take.