Freethought Nation

Solar Power Breakthrough

"It’s the Holy Grail at clean energy research labs all over the world and something which could address long term energy issues domestically and beyond: more efficient photovoltaic solar. We’ve told you about scientists studying full-spectrum cells, using textured substrates, trying self-regenerating nanomaterials – we’ve even reported on an anti-reflective film inspired by a coating found in moth eyes. Now a Stanford team is claiming a breakthrough in making cheaper, more efficient panels by adding a single layer of organic molecules to solar cells.

The researchers studied this technique on a fairly new type of solar cell that uses tiny particles of semiconductors called quantum dots. Quantum dot solar cells are cheaper to produce than traditional silicon cells, but they haven’t caught on due to their relative inefficiency.

For Stacey Bent, a chemical engineering professor at Stanford, this represented something of a challenge. She knew that solar cells made of a single material have a maximum efficiency of about 31 percent, a limitation of the fixed energy level they can absorb, and that quantum dot solar cells didn’t share this limitation. “Quantum dots can be tuned to absorb a certain wavelength of light just by changing their size,” the Stanford report on her research says. “And they can be used to build more complex solar cells that have more than one size of quantum dot, allowing them to absorb multiple wavelengths of light.”

So Bent and her team coated a titanium dioxide semiconductor in their quantum dot solar cell with a very thin single layer of organic molecules. They found that just that single layer, less than a nanometer thick, was enough to triple the efficiency of the solar cells."

solar cell manufacturing costs cut by an estimated 50 percent

"On Friday, Secretary of Energy Stephen Chu announced a "game changing" development in solar energy. A company called 1366 Technologies, headquartered in Lexington, Mass., has developed a silicon solar wafer that would cut the cost of solar cell manufacturing by an estimated 50 percent.

Unlike traditional wafers--which are sliced from a large block, resulting in considerable losses of material (up to 50 percent)--these new wafers are individually cast to specific measurements, a more efficient model of production.

In 2009, ARPA-E made an initial $4 million dollar investment in 1366 Technologies, and on Friday, announced it would make an additional $150 million dollar loan guarantee to take the company's research and development to the next level.

If projections regarding cost savings are accurate, solar may be on its way to becoming competitive with traditional fossil-fuels -- though some in the industry remain concerned about barriers still in place.

"There are two main areas of concern: price and value," said Brian Keane, president of Smart Power, a green energy marketing group. Keane explained that the primary "value" of solar "is that it's good for the environment. But quite frankly, no American actually thinks that's good value."

Keane says that U.S. consumers need to be convinced that solar is a viable proposition. "The perception is that solar is an idea from the 1970s that just didn’t work. They think it’s not strong enough to power their lives, compared with oil, coal and nuclear power."

Still, Keane added, "If we can cut the price [of manufacturing] in half, that really helps us with the value proposition to the American people."

Others point to concerns around the marketplace itself. Lew Milford, president of the Clean Energy Group, a non-profit advocacy group focused on energy and climate concerns, said that many new and innovative technologies fail because they never reach commercialization. Milford called this the "valley of death" that innovative tech companies must cross after their initial rounds of funding, and the hurdle that oftentimes prevents them from becoming scalable and reaching market potential.

Milford suggested that the problem of access to capital might be solved with something like the President's suggested--"Clean Energy Bank"--to finance clean energy initiatives, but acknowledged that the highly political climate surrounding budget negotiations would complicate its creation....."

A project dedicated to our planet

"In Spring 2004, the seed of an idea a little crazy germinates in the mind of Raphael Domjan. He is 39 years old and Swiss. He was trained as an electronics engineer but he is also ambulance man, jet and glider pilot, and mountain guide. In love with Nature, he is a Jack of all trades and a fervent defender of clean energy. Like others, he feels that we rapidly need to find alternatives to our wild oil consumption but that, at the same time, the huge potential of renewable energy still need to be proven and promoted.

Unknown to the general public but citizen of the world, Raphael then imagines an extraordinary adventure inspired by his reading of Jules Verne’s novels : Travelling around the world aboard a ship which is being propelled by solar energy only! An ecological and technological journey that looks feasible to him but that no one has ever tried. But there is everything still to do, seeking partners, putting a team together, designing a ship…

The dream starts taking shape in February 2008 thanks to a meeting with M. Immo Ströher who has a long-standing interest in solar technology and possesses a solid experience in that matter. The German businessman and the Swiss Phileas Fogg are becoming partners. By combining their capital, their ideas and their inexhaustible energy, Raphaël Domjan and Immo Ströher want to demonstrate that a motor vessel can function from today without using any fossil fuel and that this clean and eco-aware navigation has undoubtedly a commercial future. After two years of designing and assembling in Kiel’s shipyards, this idea has become a project and the result is a boat that remains unique so far: the Tûranor PlanetSolar.

Beyond the dream and the emotion that this adventure creates, the PlanetSolar project brings together an international team made up of physicians, engineers, shipbuilders and sailors that contribute day after day, miles after miles, to the success of first trip around the world using solar energy."

Spinach power gets a major boost

"An interdisciplinary team of researchers at Vanderbilt University have developed a way to combine the photosynthetic protein that converts light into electrochemical energy in spinach with silicon, the material used in solar cells, in a fashion that produces substantially more electrical current than has been reported by previous "biohybrid" solar cells.

The research was reported online on Sep. 4 in the journal Advanced Materials and Vanderbilt has applied for a patent on the combination.

“This combination produces current levels almost 1,000 times higher than we were able to achieve by depositing the protein on various types of metals. It also produces a modest increase in voltage,” said David Cliffel, associate professor of chemistry, who collaborated on the project with Kane Jennings, professor of chemical and biomolecular engineering.

“If we can continue on our current trajectory of increasing voltage and current levels, we could reach the range of mature solar conversion technologies in three years.”

The researchers’ next step is to build a functioning PS1-silicon solar cell using this new design. Jennings has an Environmental Protection Agency award that will allow a group of undergraduate engineering students to build the prototype. The students won the award at the National Sustainable Design Expo in April based on a solar panel that they had created using a two-year old design. With the new design, Jennings estimates that a two-foot panel could put out at least 100 milliamps at one volt – enough to power a number of different types of small electrical devices.
Harnessing the power of spinach

More than 40 years ago, scientists discovered that one of the proteins involved in photosynthesis, called Photosystem 1 (PS1), continued to function when it was extracted from plants like spinach. Then they determined PS1 converts sunlight into electrical energy with nearly 100 percent efficiency, compared to conversion efficiencies of less than 40 percent achieved by manmade devices. This prompted various research groups around the world to begin trying to use PS1 to create more efficient solar cells........."

- Vanderbilt University