[amor de cosmos]

Solar panel manufacturing is greener in Europe than China, study says
By Louise Lerner • May 29, 2014

Solar panels made in China have a higher overall carbon footprint and are likely to use substantially more energy during manufacturing than those made in Europe, said a new study from Northwestern University and the U.S. Department of Energy’s Argonne National Laboratory. The report compared energy and greenhouse gas emissions that go into the manufacturing process of solar panels in Europe and China.

“We estimated that a solar panel’s carbon footprint is about twice as high when made in China and used in Europe, compared to those locally made and used in Europe,” said Fengqi You, assistant professor of chemical and biological engineering at Northwestern and corresponding author on the paper.

“While it might be an economically attractive option to move solar panel manufacturing from Europe to China, it is actually less sustainable from the life cycle energy and environmental perspective—especially under the motivation of using solar panels for a more sustainable future,” he said.

The team performed a type of systematic evaluation called life cycle analysis to come up with these hard data. Life cycle analysis tallies up all the energy used to make a product—energy to mine raw materials, fuel to transport the materials and products, electricity to power the processing factory, and so forth. This provides a more accurate picture of the overall energy consumed and produced and the environmental impact of making and using a solar panel.

Assuming that a solar panel is made of silicon—by far the most common solar panel material—and is installed in sunny southern Europe, a solar panel made in China would take about 20 to 30 percent longer to produce enough energy to cancel out the energy used to make it. The carbon footprint is about twice as high.

The biggest reason is that China has fewer environmental and efficiency standards for its factories and plants and generates more electricity from coal and other non-renewable sources, the authors said.

“It takes a lot of energy to extract and process solar-grade silicon, and in China, that energy tends to come from dirtier and less efficient energy sources than it does in Europe,” said Argonne scientist and co-author Seth Darling. “This gap will likely close over time as China strengthens environmental regulations.”

http://www.anl.gov/articles/solar-pa...ina-study-says
http://www.sciencedaily.com/releases...0529154151.htm
http://www.rdmag.com/news/2014/05/st...r-europe-china

More sustainable thermosolar plants thanks to the hybridization with biomethane

The Hysol project aims to integrate biomethane in concentrating solar thermal power plants to achieve a better efficiency, productive capacity and a reduction in its carbon footprint.

The integration of biomethane in concentrating solar thermal power plants would facilitate the commercial introduction of concentrating solar power (CSP) technology in the energy market, reducing both financial and environmental costs. Researchers belong to the European consortium of the Hysol project, who is led by the ACS-Cobra company, with the participation of Universidad Politécnica de MadridUniversidad Politécnica de Madrid (UPM) researchers. Currently, they are studying the integration process of biomethane. In order to conduct the validation of this process, this project is expected to build a pre-industrial plant located at the cluster of thermosolar innovation of Manchasol.

Sun is a free, renewable energy resource that can be used for large-scale electricity production. When using CSP technology, extremely high temperatures (400-1000 ºC) are reached which can move thermodynamic cycles similar to that are used in conventional power plants.

Spain is a pioneering country in the technological and commercial development of CSP technology, with 48 operating plants of 2204 Wme of capacity. United States has 20 thermosolar plants (956 MWe) and other countries with access to optimal solar resources (China, India, Israel, Mexico, South Africa, Algeria, Egypt, Morocco, Australia, Chile, etc) have commercial plants or are under construction. The International Energy Agency (IEA) expects a large increase in the contribution of this technology for the worldwide electrical production with a capacity of 147 GW by 2020 and 1089 GW by 2050.

http://www.upm.es/internacional/UPM/...0009c7648aRCRD
http://www.sciencedaily.com/releases...0527085514.htm

05/29/2014
JCAP Stabilizes Common Semiconductors For Solar Fuels Generation
Caltech researchers devise a method to protect the materials in a solar-fuel generator

Researchers around the world are trying to develop solar-driven generators that can split water, yielding hydrogen gas that could be used as clean fuel. Such a device requires efficient light-absorbing materials that attract and hold sunlight to drive the chemical reactions involved in water splitting. Semiconductors like silicon and gallium arsenide are excellent light absorbers—as is clear from their widespread use in solar panels. However, these materials rust when submerged in the type of water solutions found in such systems.

Now Caltech researchers at the Joint Center for Artificial Photosynthesis (JCAP) have devised a method for protecting these common semiconductors from corrosion even as the materials continue to absorb light efficiently. The finding paves the way for the use of these materials in solar-fuel generators.

"For the better part of a half century, these materials have been considered off the table for this kind of use," says Nate Lewis, the George L. Argyros Professor and professor of chemistry at Caltech, and the principal investigator on the paper. "But we didn't give up on developing schemes by which we could protect them, and now these technologically important semiconductors are back on the table."

http://www.caltech.edu/content/jcap-...els-generation
http://www.sciencedaily.com/releases...0529142352.htm

Fecha de publicación: 29/05/2014
The quantum mechanisms of organic devices for alternative solar panels are revealed
The research, in which the UPV/EHU Professor Angel Rubio is participating, is being published this week in the journal Science

Silicon panel-based technology requires a very costly, contaminating manufacturing process, while organic photovoltaic (OPV) devices have been positioned as one of the most attractive alternatives as a source of solar energy.

This research has made a ground-breaking discovery because it is the first time that the quantum mechanisms that trigger the photovoltaic function of these devices have been deciphered. Angel Rubio, Professor of Condensed Matter Physics at the Faculty of Chemistry of the UPV/EHU-University of the Basque Country, director of the Nano-Bio Spectroscopy Group, and associate researcher of the Donostia International Physics Center (DIPC), has participated in the research conducted in this field in collaboration with various centres in Germany, Italy and France. The research is being published in the prestigious journal Science.

These organic devices use a photosensitive polymer linked to a carbon nanostructure that functions as a current collector. When light falls on the device, the polymer traps the particles of light and induces the ultrafast transmission of electrons to the nanostructure through an electron impulse in the order of femtoseconds (fs), in other words, 10-15 seconds. Evidence was recently found to confirm this ultrafast transfer, but the research of Rubio and his team has gone a step further because it has succeeded in deciphering the element mechanism that unleashes the electron transfer between the polymer and the nanostructure. The first-principal simulations in a simplified model predicted that the coherent vibrations are the ones that dictate the periodic transfer of charge between the polymer and the fullerene.

http://www.ehu.es/p200-hmencont/en/c...info/info.html
http://www.sciencedaily.com/releases...0530121701.htm

Quantum mechanics matters: First real time movies of the light-to-current conversion in an organic solar cell

Photovoltaic cells directly convert sun light into electricity and hence are key technological devices to meet one of the challenges that mankind has to face in this century: a sustainable and clean production of renewable energy. Organic solar cells, using polymeric materials to capture sun light, have particularly favorable properties. They are low-cost, light-weight and flexible, and their color can be adapted by varying the material composition. Such solar cells typically consist of nanostructured blends of conjugated polymers (long chains of carbon atoms), acting as light absorbers, and fullerenes (nanoscale carbon soccer balls), acting as electron acceptors. The primary and most elementary step in the light-to-current conversion process, the light-induced transfer of an electron from the polymer to the fullerene, occurs at such a staggering speed that it has previously proven difficult to follow it directly.

Now, a team of German and Italian researchers from Oldenburg, Modena and Milano reported the first real time movies of the light-to-current conversion process in an organic solar cell. In a report published in the May 30 issue of Science Magazine, the researchers show that the quantum-mechanical, wavelike nature of electrons and their coupling to the nuclei is of fundamental importance for the charge transfer in an organic photovoltaic device.

*snip*

Will the new results immediately lead to better solar cells? “Such ultrafast spectroscopic studies, and in particular their comparison with advanced theoretical modelling, provide impressive and most direct insight in the fundamental phenomena that initiate the organic photovoltaic process. They turn out to be very similar to the strategies developed by Nature in photosynthesis.”, says Lienau. “Recent studies indicate that quantum coherence apparently plays an important role in that case. Our new result provide evidence for similar phenomena in functional artificial photovoltaic devices: a conceptual advancement which could be used to guide the design of future artificial light-harvesting systems in an attempt to match the yet unrivalled efficiency of natural ones."

http://www.uno.uni-oldenburg.de/63472.html
http://www.sciencedaily.com/releases...0530124431.htm

How solar power is challenging utilities
The solar industry has a bigger stake in the utility industry now more than ever. But what does this mean for the electric utility sector?
By Elias Hinckley, Guest blogger / May 29, 2014

This week Barclays downgraded the high-grade bond market for the entire electric utility sector because “we believe that a confluence of declining cost trends in distributed solar photovoltaic (PV) power generation and residential-scale power storage is likely to disrupt the status quo.” While this is not the first statement about vulnerability of electric utilities to competition from new technology it is the most important to date.

Electric Utilities vs. Solar

Barclays Sees Technology Winning – Soon

Downgrading Utility Bonds is Really Really Big Deal

What Happens Next?

http://www.csmonitor.com/Environment...ging-utilities