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Think like a fish not like a bird, say researchers trying to harvest energy from water currents. Their new fish-inspired power generator can work in slow-moving currents where traditional turbines are less effective.
Tidal streams and moving rivers in the United States could generate 140 billion kilowatt-hours per year, or about 3.5 percent of the nation's electricity demand, according to the Electric Power Research Institute (EPRI).
Most of the attempts to tap this potential have employed underwater windmills. These so-called tidal turbines use the force of lift to turn their blades.
"We live in air so we are used to lifting surfaces that support birds, sail boats and airplanes," said Michael Bernitsas of the University of Michigan.
In water, however, Nature has devised a different strategy. Most natural swimmers — from tiny sperm to giant whales — create vortices (or little whirlpools) that they push off of to propel themselves forward.
Bernitsas realized that these same vortices could be used to drive a generator. He and his colleagues have created a machine called VIVACE (Vortex Induced Vibrations for Aquatic Clean Energy), whose cylinders oscillate up and down in moving waters.
Read
more about the generator at Live Science
Japanese sailor and environmentalist Kenichi Horie has completed a 110-day solo voyage across the Pacific Ocean in a boat propelled by wave power to claim another world first.
Weak waves and opposing ocean currents delayed his arrival, which was originally set for late May.
"When waves were weak, the boat slowed down. That's the problem to be solved," the adventurer told reporters Saturday from aboard his catamaran Suntory Mermaid II off the Kii Peninsula in western Japan.
The 9.5 metre (31-foot) boat is equipped with two special fins at the front which can move like a dolphin's tail each time the vessel rises or falls with the rhythm of the waves.
Horie, who will turn 70 in September, reached his destination in the channel between the main Japanese islands of Honshu and Shikoku just before midnight (1500 GMT Friday) after covering some 7,000 kilometres (3,780 nautical miles) from Hawaii without a port call.
Via
Physorg.com
The UN Environment Program estimates that there are 46,000 pieces of plastic litter in every square mile of ocean, and a swirling vortex of trash twice the size of Texas has spawned in the North Pacific.
Plastic bags, once icons of customer convenience, cost more than 1.6 billion barrels of oil per year and leave the environment to foot the bill. Each year the world produces 500 billion bags, and they take up to 1,000 years to decompose. They take up space in landfills, litter our streets and parks, pollute the oceans and kill the wildlife that eat them.
Eco-friendly legislation that targets the production and distribution of plastic bags has been introduced in Israel, San Francisco, Ireland and China. Addiionally, a recent scientific discovery (see below) offers a potential long-term solution to the global plastic crisis.
Since stories have started surfacing more recently, many have wondered, if the rumors are true. Are there really 'continents', or massive floating garbage patches residing in the Pacific? Apparently, the rumors are true, and these unsightly patches are reportedly killing marine life and releasing poisons that enter the human food chain, as well. However, before you start imagining a plastic version of Maui, keep in mind that these plastic patches certainly aren't solid surfaced islands that you could build a house on! Ocean currents have collected massive amounts of garbage into a sort of plastic "soup" where countless bits of discarded plastic float intertwined just beneath the surface. Indeed, the human race has really made its mark. The enormous Texas-sized plastic patch is estimated to weigh over 3 million tons.
Sadly, marine researcher Charles Moore at the Algalita Marina Research Foundation in Long Beach says there’s no practical fix for the problem. He has been studying the massive patch for the past 10 years, and said the debris is to the point where it would be nearly impossible to extract.
"Any attempt to remove that much plastic from the oceans - it boggles the mind," Moore said from Hawaii, where his crew is docked. "There's just too much, and the ocean is just too big."
"When oil prices soared in 2005, that changed a lot of people's perspective, because bioplastic became quite cost-competitive," she says. "All of a sudden it wasn't just about doing the right thing."
Read from the
Daily Galaxy.
Biomimicry - or designs based on natural systems - is one of the most intriguing methods for designers and engineers to create innovative and efficient solutions to problems. Inspired by forms and functions found in nature, this approach to sustainable design allows for environmentally friendly solutions for energy, waste reduction and a bevy of other design challenges. Using biomimicry as the guiding design principle, the Australian firm BioPower Systems has developed Biowave: an ocean power system that harnesses energy by mimicking the motion of underwater plants in the ocean currents to generate electricity.
Biowave mimics the swaying motion of the sea plants found in the ocean bed. The system looks like three buoyant blades which are constantly oscillating to the motion of the sea. As they sway in the tide, electricity is generated. If at any point the system is in danger because of the strong currents, it simply lies in flat until the ocean calms down.
BioPower Systems is currently testing a prototype off the coast of Tasmania. A prototype unit of 250kw will inform the company on how to best deploy a larger scale system which in turn is expected to provide power to Flinders and King islands, and in the future, if successful, the entire state of Victoria, home of the city of Melbourne.
Check out
Biowave via
inhabitat.com.
