Gizmodo: clean energy

UMich VIVACE Hydropower System Makes Energy From Slow Currents

Elaine Chow — Wed, 26 Nov 2008 04:30:00 EST

A new hydropower prototype from the University of Michigan could end up using even slower river and ocean currents to generate energy. VIVACE, which stands for Vortex Induced Vibrations for Aquatic Clean Energy, can generate power from as little as 2 knots, making it more useful than most turbine and water mill systems out there, which need an average of 5 to 6 knots to operate efficiently.

The system works by harnessing “vortex induced vibrations,” the thrumming caused by the flow of liquid or air over rounded objects. A cylinder placed underwater is subject to the current and starts to vibrate as liquid sticks and creates eddies on the object's opposite side. It's the same scientific principle that caused the collapse of the Tacoma Narrows bridge in 1940.

"For the past 25 years, engineers—myself included—have been trying to suppress vortex induced vibrations. But now at Michigan we're doing the opposite. We enhance the vibrations and harness this powerful and destructive force in nature," said VIVACE developer Michael Bernitsas, a professor in the U-M Department of Naval Architecture and Marine Engineering.

Just a few cylinders could possibly power an anchored ship or a lighthouse. An array of VIVACE cylinders about the size of a running track could produce energy at 5.5 cents per kilowatt hour and power about 100,000 houses. U of M is now working on possibly deploying a pilot project in the Detroit River within the next 18 months. [UMich via Gizmag]

Cylinder Solar Panels Generate More Energy For Less Cost

Elaine Chow — Wed, 08 Oct 2008 01:35:00 EDT

Solyndra, a California-based solar start up, says it's figured out a way to make solar panels cheaper to install and better at producing energy—rolling them up. The company's solar panels are comprised of rows of cylindrical solar cells deposited on glass tubes, a new type of shape that purportedly lets them absorb more light during the day.

The shape also offers less wind resistance than conventional flat panels, making them cheaper and easier to mount on roofs. These advantages ultimately reduce the cost of generating power from the sun, though Solyndra couldn't give a direct answer on how much.

Considering that everyone, from Google to the Vatican, is installing a solar roof these days, Solyndra's innovations could mean a serious boost for the industry. But what's with not actually giving figures? That seems a little... shady. [Technology Review via Dvice]

World's First Tidal Turbine Farms to Power 40,000 Scottish Homes (or Pubs)

John Herrman — Tue, 30 Sep 2008 06:30:00 EDT

Following the apparent success of SeaGen, a small deployment of tidal turbines of the coast of Northern Ireland, Scottish Power is seeking approval for plans to build two farms of 20 100-foot, err, watermills promising a steady power supply for up to 40,000 homes. As with the previous example of tidal power generation, the most obvious problems have been pretty much addressed: fish, seals, and cryptozoological specimens (probably) won't be harmed by the slow-spinning blades, and shipping routes won't be affected on account of the depth of the deployment. Scottish Power claims that the project should be completed in about three years. Click the above image for a explanatory video. [BBC via CleanTechnica]