Monday, April 25, 2011

Solar power goes viral: Modified virus improves solar-cell efficiency by one-third

Solar power goes viral: Modified virus improves solar-cell efficiency by one-third

In a solar cell, sunlight hits a light-harvesting material, causing it to release electrons that can be harnessed to produce an electric current. The new MIT research, published online this week in the journal , is based on findings that carbon nanotubes — microscopic, hollow cylinders of pure carbon — can enhance the efficiency of electron collection from a solar cell's surface.

Previous attempts to use the nanotubes, however, had been thwarted by two problems. First, the making of carbon nanotubes generally produces a mix of two types, some of which act as semiconductors (sometimes allowing an electric current to flow, sometimes not) or metals (which act like wires, allowing current to flow easily). The new research, for the first time, showed that the effects of these two types tend to be different, because the semiconducting nanotubes can enhance the performance of solar cells, but the metallic ones have the opposite effect. Second, nanotubes tend to clump together, which reduces their effectiveness.

And that’s where viruses come to the rescue. Graduate students Xiangnan Dang and Hyunjung Yi — working with Angela Belcher, the W. M. Keck Professor of Energy, and several other researchers — found that a genetically engineered version of a called M13, which normally infects bacteria, can be used to control the arrangement of the nanotubes on a surface, keeping the tubes separate so they can’t short out the circuits, and keeping the tubes apart so they don’t clump.

(...) In their tests, adding the virus-built structures enhanced the to 10.6 percent from 8 percent — almost a one-third improvement.

More @

Wednesday, April 20, 2011

Leaked: 30,000 BP oil spill memos, emails and transcripts

Leaked: 30,000 BP oil spill memos, emails and transcripts | Crikey

"In the middle of last year, Greenpeace started submitted a string of Freedom of Information requests to US government agencies in relation to last year’s disastrous BP oil spill in the Gulf of Mexico.

As a result the environmental group have obtained some 30,000 memos, emails and transcripts which document the worst oil spill in American history. Taking cues from WikiLeaks, Greenpeace has begun to leak its considerable cache online for all to see.

More @ Crikey

RC car runs on soda can rings

RC car runs on soda can rings

dAlH2Orean H2 R/C Car powered by Aluminium from Aleix Llovet on Vimeo.

A pair of Spanish engineers have recently unveiled the dAlH2Orean (see what they did there?), a R/C car that runs on aluminum. Dropping a few soda can tabs into a tank of sodium hydroxide produces enough hydrogen to power the little speedster for 40 minutes – at almost 20mph.

More @ Engadget

Monday, April 18, 2011

Magnetic Effect of Light May Lead to Better Solar Power

A dramatic and surprising magnetic effect of light discovered by University of Michigan researchers could lead to solar power without traditional semiconductor-based solar cells.

The researchers found a way to make an "optical battery," said Stephen Rand, a professor in the departments of Electrical Engineering and Computer Science, Physics and Applied Physics."This could lead to a new kind of solar cell without semiconductors and without absorption to produce charge separation," Rand said. "In solar cells, the light goes into a material, gets absorbed and creates heat. Here, we expect to have a very low heat load. Instead of the light being absorbed, energy is stored in the magnetic moment. Intense magnetization can be induced by intense light and then it is ultimately capable of providing a capacitive power source."
This new technique could make solar power cheaper, the researchers say. They predict that with improved materials they could achieve 10 percent efficiency in converting solar power to useable energy. That's equivalent to today's commercial-grade solar cells.

More @ Michigan Today

Tuesday, April 12, 2011

Home Solar Panel Kits Come To Costco

Home Solar Panel Kits Come To Costco | EarthTechling

Costco members will soon be able to add solar power systems alongside power tools and pancake mix on their shopping lists. Euegene, Oregon based Grape Solar has recently announced that several of its solar kits will soon be available through Costco’s website in the ”Hardware” section under the Generators & Backup Power subcategory. Costco members will have a choice of 880W, 2300W, 3680W or 5060W ready-to-install kits, with prices ranging from around $3,600 upwards to around $18,000.

The solar kits are “grid-tied” systems that include Grape Solar panels, inverters, and racking systems that are ready to install onto the roofs of homes and other structures. Grape Solar says the kits are designed to be expandable, so customers can start small and grow their system over time if they wish. In order to facilitate installation, Grape Solar says that they developed a network of over 5,000 installers who will be available to provide locally based customer support.

Grape Solar Kit

More @ EarthTechling