Posts belonging to Category green power



Solar Power: Ninety Percent Of Captured Light Converted Into Heat

A multidisciplinary engineering team at the University of California, San Diego developed a new nanoparticle-based material for concentrating solar power plants designed to absorb and convert to heat more than 90 percent of the sunlight it captures. The new material can also withstand temperatures greater than 700 degrees Celsius and survive many years outdoors in spite of exposure to air and humidity. Their work, funded by the U.S. Department of Energy’s SunShot program, was published recently in two separate articles in the journal Nano Energy. By contrast, current solar absorber material functions at lower temperatures and needs to be overhauled almost every year for high temperature operations.

solarPanel

We wanted to create a material that absorbs sunlight that doesn’t let any of it escape. We want the black hole of sunlight,” said Sungho Jin, a professor in the department of Mechanical and Aerospace Engineering at UC San Diego Jacobs School of Engineering. Jin, along with professor Zhaowei Liu of the department of Electrical and Computer Engineering, and Mechanical Engineering professor Renkun Chen, developed the Silicon boride-coated nanoshell material. They are all experts in functional materials engineering.

Source:  http://www.jacobsschool.ucsd.edu/

Solar Plant produces twice more Than Nuclear Power Plant

A solar energy project in the Tunisian Sahara aims to generate enough clean energy by 2018 to power two million European homes. Called the TuNur project; developers, including renewable investment company Low Carbon and solar developer Nur Energie, say the site will produce twice as much energy as the average nuclear power plant. But instead of using typical photovoltaic cells that only generate power during the day; they’re using Concentrated Solar Power. Using a vast array of mirrors to concentrate and  reflect the intense Saharan sun to a central tower, water or molten salt is heated to over 500 degrees Celsius. The steamced powers a turbine which in turn generates electricity. This, says Nur Energie‘s CEO Kevin Sara, means the plant will produce electricity even when the sun is down.

 

solar power plant

 ”The technology that you can deploy in the desert is baseload renewable power; that means you can actually replace fossil fuel power plants because we can generate 24-7 using solar power,” says Kevin Sara, CEO of Nur Energie. Transmission lines will take the electricity to the Tunisian coast where a dedicated undersea cable will connect it to the European grid via a hub in northern Italy. Over ten millions euros has already gone into identifying the best location in the Tunisian Sahara to harness the intense solar radiation. “It’s quite large; it’s 10,000 hectares – a hundred square kilometres. But there’s nothing there, it’s just sand and a few bushes.

With energy security a big concern, Sara says the project has the potential to help end Europe’s reliance on fossil fuels using ‘desert power‘. “We believe that this is really opening a new energy corridor. This could be the first of many projects, and we could gradually de-carbonise the European grid using desert power, using this solar energy with storage from the Sahara desert and linked to Europe with high-voltage DC cables which are very, very low in their losses.” Sara added.
Tunisia is seeking to bolster its stability following the 2011 uprising, with lack of jobs and growth contributing to the unrest. The team behind the TuNur project hope the Saharan sunshine will be a shining light not only for renewable energy, but for the future of Tunisia.

Source: http://www.reuters.com/

How To Triple The Production Of Biogas

Researchers of the Catalan Institute of Nanoscience and Nanotechnology (ICN2), and the Universitat Autònoma de Barcelona (UAB) have developed the new BiogàsPlus, a technology which allows increasing the production of biogas by 200% with a controlled introduction of iron oxide nanoparticles to the process of organic waste treatment.

The development of BiogàsPlus was carried out by the ICN2‘s Inorganic Nanoparticle group, led by ICREA researcher Víctor Puntes, and by the Group of Organic Solid Waste Composting of the UAB School of Engineering, directed by Antoni Sánchez. The system is based on the use of iron oxide nanoparticles as an additive which “feeds” the bacteria in charge of breaking down organic matter. This additive substantially increases the production of biogas and at the same time transforms the iron nanoparticles into innocuous salt.

iron Oxyd nanoparticle
We believe we are offering a totally innovative approach to the improvement of biogas production and organic waste treatment, since this is the first nanoparticle application developed with this in mind. In addition, it offers a significant improvement in the decomposition of organic waste when compared to existing technologies”, explains Antoni Sánchez.

According to researchers, today’s biogas production is not very efficient – only 30 to 40 per cent of organic matter is converted into biogas - when compared to other energy sources. “The first tests conducted with BiogàsPlus demonstrated that product increases up to 200% the production of this combustible gas. This translates into a profitable and sustainable solution to the processing of organic waste, thus favouring the use of this renewable source of energy”, affirms Eudald Casals, ICN2 researcher participating in the project.
Source: http://www.uab.cat/

3D Printing: How To Control the Structure of Metal

Researchers at the Department of Energy’s Oak Ridge National Laboratory (ORNL) have demonstrated an additive manufacturing method to control the structure and properties of metal components with precision unmatched by conventional manufacturing processes. Ryan Dehoff, staff scientist and metal additive manufacturing lead at the Department of Energy’s Manufacturing Demonstration Facility at ORNL, presented the research this week in an invited presentation at the Materials Science & Technology 2014 conference in Pittsburgh.

3D prining metalORNL researchers have demonstrated the ability to precisely control the structure and properties of 3-D printed metal parts during formation. The electron backscatter diffraction image shows variations in crystallographic orientation in a nickel-based component, achieved by controlling the 3-D printing process at the microscale

We can now control local material properties, which will change the future of how we engineer metallic components,” Dehoff said. “This new manufacturing method takes us from reactive design to proactive design. It will help us make parts that are stronger, lighter and function better for more energy-efficient transportation and energy production applications such as cars and wind turbines.”
We’re using well established metallurgical phenomena, but we’ve never been able to control the processes well enough to take advantage of them at this scale and at this level of detail,” said Suresh Babu, the University of Tennessee-ORNL Governor’s Chair for Advanced Manufacturing. “As a result of our work, designers can now specify location specific crystal structure orientations in a part.”

Source: http://www.ornl.gov

Nano Light Consumes Hundred Times Less Than A LED

Scientists from Tohoku University in Japan have developed a new type of energy-efficient flat light source based on carbon nanotubes with very low power consumption of around 0.1 Watt for every hour‘s operation — about a hundred times lower than that of an LED. Electronics based on carbon, especially carbon nanotubes (CNTs), are emerging as successors to silicon for making semiconductor materials, And they may enable a new generation of brighter, low-power, low-cost lighting devices that could challenge the dominance of light-emitting diodes (LEDs) in the future and help meet society’s ever-escalating demand for greener bulbs.
nanolightPlane-lighting homogeneity image of a planar light source device through a neutral density filter
Our simple ‘diode’ panel could obtain high brightness efficiency of 60 Lumen per Watt, which holds excellent potential for a lighting device with low power consumption,” said Norihiro Shimoi, the lead researcher and an associate professor of environmental studies at the Tohoku University. “We have found that a cathode with highly crystalline single-walled carbon nanotubes and an anode with the improved phosphor screen in our diode structure obtained no flicker field emission current and good brightness homogeneity,” Shimoi said.
Source: http://www.aip.org/

Electric Car: Hydrogen Fuel Cells 40 Times Cheaper

Researchers from Umea University – Sweden – and chinese collegues show how a unique nano-alloy composed of palladium nano-islands embedded in tungsten nanoparticles creates a new type of catalysts for highly efficient oxygen reduction, the most important reaction in hydrogen fuel cells. Fuel cell systems represent a promising alternative for low carbon emission energy production. Traditional fuel cells are however limited by the need of efficient catalysts to drive the chemical reactions involved in the fuel cell. Historically, platinum and its alloys have frequently been used as anodic and cathodic catalysts in fuel cells, but the high cost of platinum, due to its low abundance, motivates researchers to find efficient catalysts based on earth-abundant elements. The explanation for the very high efficiency is the unique morphology of the alloy. It is neither a homogeneous alloy, nor a fully segregated two-phase system, but rather something in between.

hydrogen fuel cellsCaption: A schematic model of the unique morphology of the alloy. The Pd-islands (light-brown spheres) are embedded in an environment of tungsten (blue spheres). Oxygen are represented by red spheres, and hydrogen by white spheres.

In our study we report a unique novel alloy with a palladium (Pd) and tungsten (W) ratio of only one to eight, which still has similar efficiency as a pure platinum catalyst. Considering the cost, it would be 40 times lower,” says Thomas Wågberg, Senior lecturer at Department of Physics, Umeå University.
The unique formation of the material is based on a synthesis method, which can be performed in an ordinary kitchen micro-wave oven purchased at the local supermarket. If we were not using argon as protective inert gas, it would be fully possible to synthesize this advanced catalyst in my own kitchen! ,” says Thomas Wågberg.
The findings are published in the scientific journal Nature Communications.

Source: http://www.teknat.umu.se/

Electric Car Batteries Recharge in Two Minutes

Scientists from Nanyang Technological University (NTU Singapore) have developed a new battery that can be recharged up to 70 per cent in only 2 minutes. The battery will also have a longer lifespan of over 20 years.
Electric vehicles are currently inhibited by long recharge times of over 4 hours and the limited lifespan of batteries.
This next generation of lithium-ion batteries will enable electric vehicles to charge 20 times faster than the current technology. With it, electric vehicles will also be able to do away with frequent battery replacements. The new battery will be able to endure more than 10,000 charging cycles20 times more than the current 500 cycles of today’s batteries.
NTU Singapore‘s scientists replaced the traditional graphite used for the anode (negative pole) in lithium-ion batteries with a new gel material made from titanium dioxide, an abundant, cheap and safe material found in soil.
Invented by Associate Professor Chen Xiaodong from the School of Materials Science and Engineering at NTU Singapore, the science behind the formation of the new titanium dioxide gel was published in the latest issue of Advanced Materials.

2014 Renault

While the cost of lithium-ion batteries has been significantly reduced and its performance improved since Sony commercialised it in 1991, the market is fast expanding towards new applications in electric mobility and energy storage,” said Prof Yazami.
There is still room for improvement and one such key area is the power density — how much power can be stored in a certain amount of space — which directly relates to the fast charge ability. Ideally, the charge time for batteries in electric vehicles should be less than 15 minutes, which Prof Chen’s nanostructured anode has proven to do.“.
Source: http://news.asiaone.com

Cheap Hydrogen Fuel

The race is on to optimize solar energy’s performance. More efficient silicon photovoltaic panels, dye-sensitized solar cells, concentrated cells and thermodynamic solar plants all pursue the same goal: to produce a maximum amount of electrons from sunlight. Those electrons can then be converted into electricity to turn on lights and power your refrigerator.
hydrogen-electric car At the Laboratory of Photonics and Interfaces from Ecole Polytechnique Fédérale de Lausanne (EPFL) – Switzerland -, led by Michael Grätzel, where scientists invented dye solar cells that mimic photosynthesis in plants, they have also developed methods for generating fuels such as hydrogen through solar water splitting. To do this, they either use photoelectrochemical cells that directly split water into hydrogen and oxygen when exposed to sunlight, or they combine electricity-generating cells with an electrolyzer that separates the water molecules.

By using the latter technique, Grätzel’s post-doctoral student Jingshan Luo and his colleagues were able to obtain a performance spectacular: their device converts into hydrogen 12.3 percent of the energy diffused by the sun on perovskite absorbers – a compound that can be obtained in the laboratory from common materials, such as those used in conventional car batteries, eliminating the need for rare-earth metals in the production of usable hydrogen fuel. This high efficiency provides stiff competition for other techniques used to convert solar energy. But this method has several advantages over others:
Both the perovskite used in the cells and the nickel and iron catalysts making up the electrodes require resources that are abundant on Earth and that are also cheap,” explained Jingshan Luo. “However, our electrodes work just as well as the expensive platinum-based models customarily used.”
The research is being published today in the journal Science.
Source: http://actu.epfl.ch/

Extremely Bendable Electronics

As tech company LG demonstrated this summer with the unveiling of its 18-inch flexible screen, the next generation of roll-up displays is tantalizingly close. Researchers are now reporting in the journal ACS Nano a new, inexpensive and simple way to make transparent, flexible transistors — the building blocks of electronics — that could help bring roll-up smartphones with see-through displays and other bendable gadgets to consumers in just a few years.
Yang Yang and colleagues note that transistors are traditionally made in a multi-step photolithography process, which uses light to print a pattern onto a glass or wafer. Not only is this approach costly, it also involves a number of toxic substances. Finding a greener, less-expensive alternative has been a challenge. Recently, new processing techniques using metal oxide semiconductors have attracted attention, but the resulting devices are lacking in flexibility or other essential traits. Now Yang’s team developed inks that create patterns on ultrathin, transparent devices when exposed to light.
transparent transistorsThis transparent transistor, which functions even when wrapped around a thin pen, could help make flexible electronics widely accessible.
The main application of our transistors is for next-generation displays, like OLED or LCD displays,” said Yang. “Our transistors are designed for simple manufacturing. We believe this is an important step toward making flexible electronics widely accessible.
Source: http://www.acs.org/

Electric Car: New Battery Eight Times More Powerful

Researchers from the General Motors Global Research & Development Center in Warren (Michigan), have replaced the metal oxide with cheaper and lighter sulfur, to make Li-S batteries. Theorically, this new batteries pack five to eight times the energy of existing technology.
2014 Renault
One of the main problems with the sulfur approach, however, is that Li-S compounds escape from where they’re supposed to be, which causes the battery to lose charge quickly. The team set out to find a way to contain the problem.
The study appears in the ACS journal Nano Letters.
Source: http://pubs.acs.org/