A new prototype of a wave power generator has been unveiled in England, and its inventors followed the creed espoused by Leonardo da Vinci: “Simplicity is the ultimate sophistication.” The new wave power device, known as Anaconda, is a basic tube made from rubber and fabric and filled with water. It is still in trial phase, but its creators, optimistic about its potential as a source of mass power, are confident it will be cheaper than a wind farm generating the equivalent amount of power and less controversial in terms of public protest since the devices will be below the sea [Telegraph].
The Anaconda rides waves in the ocean, which create bulges along the tubing that travel along its length gathering energy. At the end of the tube, the surge of energy drives a turbine and generates electricity [BBC News]. While similar technology has already been deployed in the coastal waters near Portugal, the inventors of the Anaconda say its mostly rubber composition and its few moving parts combine to give it a sturdy and resilient edge in the tumultuous ocean. Until now, “the problem holding back wave energy machines is they tend to deteriorate over time in the harsh marine environment” [The Guardian], said Rod Rainey, an engineer with the Anaconda project.
A marine engineer and naval architect has designed a new way of drawing energy out of slow-moving rivers and gentle tides. The researcher says the unobtrusive device, which was inspired by the way fish move through the water, could be set down on riverbeds or suspended in the ocean just about anywhere. Existing technologies which use water power, relying on the action of waves, tides or faster currents created by dams, are far more limited in where they can be used, and also cause greater obstructions when they are built in rivers or the sea. Turbines and water mills need an average current of five or six knots to operate efficiently, while most of the earth’s currents are slower than three knots [Telegraph].
Engineer Michael Bernitsas’s device is called VIVACE, which stands for Vortex Induced Vibrations for Aquatic Clean Energy. How does the technology work? A cylinder-shaped object in the water current causes alternating vortices to form above and below the cylinder. The vortices push and pull the passive cylinder up and down on its springs, creating mechanical energy. Then, the machine converts the mechanical energy into electricity [Greenbang]. Bernitsas explains that fish also create vortices as they swim, and in a large school each fish curves around the vortices left by the fish in front, using the tiny whirlpools to propel themselves forward.
The first commercial energy station powered by ocean waves started up yesterday three miles off the Portuguese coast. The machine, which resembles a giant red sea snake, generates electricity that’s transmitted via an underwater cable to the nation’s power grid. Two more machines are expected to be added in the coming weeks, allowing the “wave farm” to generate a total of 2.25 megawatts, enough to supply 1,500 households with electricity [Reuters]. If successful, a second phase will see energy generation rise to 21 megawatts from a further 25 machines providing electricity for 15,000 Portuguese homes [CNN].
Environmentalists love the idea of generating power from the natural motion of waves and tides, as the ocean’s energy is bountiful, reliable, and creates no greenhouse gases. But the technology has been slow to mature. Last year, a wave-power machine sank off the Oregon coast. Blades have broken off experimental tidal turbines in New York’s turbulent East River [The New York Times]. A problem with offshore moorings also delayed the Portuguese project for about a year. But wave power proponents say that some problems are inevitable with a new technology, and that most of the kinks have now been ironed out.