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Scooped by Dr. Stefan Gruenwald!

New efficiency record for solar hydrogen production is 14 percent

New efficiency record for solar hydrogen production is 14 percent | Amazing Science |

An international team has succeeded in considerably increasing the efficiency for direct solar water splitting with a tandem solar cell whose surfaces have been selectively modified. The new record value is 14 percent and thus tops the previous record of 12.4 percent, broken now for the first time in 17 years. Researchers from Helmholtz-Zentrum Berlin, TU Ilmenau, Fraunhofer ISE and California Institute of Technology participated in the collaboration. The results are published in Nature Communications.

Solar energy is abundantly available globally, but unfortunately not constantly and not everywhere. One especially interesting solution for storing this energy is artificial photosynthesis. This is what every leaf can do, namely converting sunlight to chemical energy. That can take place with artificial systems based on semiconductors as well. These use the electrical power that sunlight creates in individual semiconductor components to split water into oxygen and hydrogen. Hydrogen possesses very high energy density, can be employed in many ways and could replace fossil fuels. In addition, no carbon dioxide harmful to the climate is released from hydrogen during combustion, instead only water. Until now, manufacturing of solar hydrogen at the industrial level has failed due to the costs, however. This is because the efficiency of artificial photosynthesis, i.e. the energy content of the hydrogen compared to that of sunlight, has simply been too low to produce hydrogen from the sun economically.

Now a team from TU Ilmenau, Helmholtz-Zentrum Berlin (HZB), the California Institute of Technology as well as the Fraunhofer ISE has considerably exceeded this record value. Lead author Matthias May, active at TU Ilmenau and the HZB Institute for Solar Fuels, processed and surveyed about one hundred samples in his excellent doctoral dissertation to achieve this. The fundamental components are tandem solar cells of what are known as III-V semiconductors. Using a now patented photo-electrochemical process, May could modify certain surfaces of these semiconductor systems in such a way that they functioned better in water splitting.

"We have electronically and chemically passivated in situ the aluminium-indium-phosphide layers in particular and thereby efficiently coupled to the catalyst layer for hydrogen generation. In this way, we were able to control the composition of the surface at sub-nanometre scales", explains May. There was enormous improvement in long-term stability as well. At the beginning, the samples only survived a few seconds before their power output collapsed. Following about a year of optimising, they remain stable for over 40 hours. Further steps toward a long-term stability goal of 1000 hours are already underway.

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Graphene Converts Heat Into Electricity

Graphene Converts Heat Into Electricity | Amazing Science |

Graphene was first isolated at the University of Manchester in 2004 by Sir Andre Geim and Sir Kostya Novoselov. In 2010, they were awarded the Nobel Prize for Physics for their discovery. Graphene’s most unique property is that it is only 1 atom thick, making it the first 2-dimensional material. Today, the university remains the home of graphene research, with over 40 industrial partners working on graphene-related projects.

Recently, its scientists, working with European Thermodynamics Ltd, created low-cost thermoelectric materials that could be used to capture heat from automobiles and convert it into electricity. That electricity can then be used to recharge the batteries in hybrid, plug-in hybrid, and electric cars to give them more range.

The team—led by Prof Ian Kinloch, Prof Robert Freer, and Yue Lin—added a small amount of graphene to strontium titanium oxide. The resulting composite was able to convert heat that would otherwise be wasted into an electric current over a broad temperature range, beginning at room temperature. Previously, thermoelectric materials only functioned at extremely high temperatures around 700 degrees Celsius.

“Our findings show that by introducing a small amount of graphene to the base material can reduce the thermal operating window to room temperature which offers a huge range of potential for applications,” says Prof Freer. “The new material will convert 3-5% of the heat into electricity. That is not much but, given that the average vehicle loses roughly 70% of the energy supplied to it by its fuel to waste heat and friction, recovering even a small percentage of this with thermoelectric technology would be worthwhile.”

The numbers get a bit confusing, but if a conventional internal combustion engine only converts 30% of its fuel into forward motion, recapturing just 3% of its wasted heat could translate into a 10% improvement in fuel economy. Car manufacturers today would be thrilled to make their cars 10% more fuel efficient as they struggle to comply with tough new regulations set to begin shortly in the US and Europe.

Patrick Gaddy's curator insight, September 14, 10:29 AM

This Graphene material could be very useful. As the article states Graphene can be in any shape, it converts 3% of wasted heat the heat produced into energy, and it harder than diamond and stronger than steel so it has many uses for it. Now it just needs more work done on it.

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New solar cell absorbs high-energy blue light at 30-fold higher concentration than conventional cells

New solar cell absorbs high-energy blue light at 30-fold higher concentration than conventional cells | Amazing Science |
By combining designer quantum dot light-emitters with spectrally matched photonic mirrors, a team of scientists with Berkeley Lab and the University of Illinois created solar cells that collect blue photons at 30 times the concentration of conventional solar cells, the highest luminescent concentration factor ever recorded. This breakthrough paves the way for the future development of low-cost solar cells that efficiently utilize the high-energy part of the solar spectrum.

"We've achieved a luminescent concentration ratio greater than 30 with an optical efficiency of 82-percent for blue photons," says Berkeley Lab director Paul Alivisatos, who is also the Samsung Distinguished Professor of Nanoscience and Nanotechnology at the University of California Berkeley, and director of the Kavli Energy Nanoscience Institute (ENSI), was the co-leader of this research. "To the best of our knowledge, this is the highest luminescent concentration factor in literature to date."

Alivisatos and Ralph Nuzzo of the University of Illinois are the corresponding authors of a paper in ACS Photonics describing this research entitled "Quantum Dot Luminescent Concentrator Cavity Exhibiting 30-fold Concentration." Noah Bronstein, a member of Alivisatos's research group, is one of three lead authors along with Yuan Yao and Lu Xu. Other co-authors are Erin O'Brien, Alexander Powers and Vivian Ferry.

The solar energy industry in the United States is soaring with the number of photovoltaic installations having grown from generating 1.2 gigawatts of electricity in 2008 to generating 20-plus gigawatts today, according to the U.S. Department of Energy (DOE). Still, nearly 70-percent of the electricity generated in this country continues to come from fossil fuels. Low-cost alternatives to today's photovoltaic solar panels are needed for the immense advantages of solar power to be fully realized. One promising alternative has been luminescent solar concentrators (LSCs).

Unlike conventional solar cells that directly absorb sunlight and convert it into electricity, an LSC absorbs the light on a plate embedded with highly efficient light-emitters called "lumophores" that then re-emit the absorbed light at longer wavelengths, a process known as the Stokes shift. This re-emitted light is directed to a micro-solar cell for conversion to electricity. Because the plate is much larger than the micro-solar cell, the solar energy hitting the cell is highly concentrated.

With a sufficient concentration factor, only small amounts of expensive III−V photovoltaic materials are needed to collect light from an inexpensive luminescent waveguide. However, the concentration factor and collection efficiency of the molecular dyes that up until now have been used as lumophores are limited by parasitic losses, including non-unity quantum yields of the lumophores, imperfect light trapping within the waveguide, and reabsorption and scattering of propagating photons.

"We replaced the molecular dyes in previous LSC systems with core/shell nanoparticles composed of cadmium selenide (CdSe) cores and cadmium sulfide (CdS) shells that increase the Stokes shift while reducing photon re-absorption," says Bronstein.

Antonio Rojas's curator insight, September 14, 10:45 AM

        I believe that what they are doing will help us out a lot in the long run. They are making more advances to the original solar cell. The advanced solar cells are becoming more useful and collect 30 times more of the suns energy. With that being said can you imagine how much more clean and efficient energy we can use? this article explains how these advances are being done and what they can do.

Patrick Gaddy's curator insight, September 14, 11:12 AM

It's like some kind of video game puzzle. Let me explain they have panels to take in sunlight then concentrate the light into a smaller solar cell to collect the energy. This'll save on the cost on materials for the solar cells themselves because they're smaller.

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Artificial Leaf Harnesses Sunlight for Efficient Fuel Production

Artificial Leaf Harnesses Sunlight for Efficient Fuel Production | Amazing Science |

Generating and storing renewable energy, such as solar or wind power, is a key barrier to a clean-energy economy. When the Joint Center for Artificial Photosynthesis (JCAP) was established at Caltech and its partnering institutions in 2010, the U.S. Department of Energy (DOE) Energy Innovation Hub had one main goal: a cost-effective method of producing fuels using only sunlight, water, and carbon dioxide, mimicking the natural process of photosynthesis in plants and storing energy in the form of chemical fuels for use on demand. Over the past five years, researchers at JCAP have made major advances toward this goal, and they now report the development of the first complete, efficient, safe, integrated solar-driven system for splitting water to create hydrogen fuels.

"This result was a stretch project milestone for the entire five years of JCAP as a whole, and not only have we achieved this goal, we also achieved it on time and on budget," says Caltech's Nate Lewis, George L. Argyros Professor and professor of chemistry, and the JCAP scientific director.

The new solar fuel generation system, or artificial leaf, is described in the August 27 online issue of the journal Energy and Environmental Science. The work was done by researchers in the laboratories of Lewis and Harry Atwater, director of JCAP and Howard Hughes Professor of Applied Physics and Materials Science.

"This accomplishment drew on the knowledge, insights and capabilities of JCAP, which illustrates what can be achieved in a Hub-scale effort by an integrated team," Atwater says. "The device reported here grew out of a multi-year, large-scale effort to define the design and materials components needed for an integrated solar fuels generator."

satish's curator insight, August 29, 1:24 AM

कृत्रिम पान किंवा प्रकाश संश्लेषण क्रियेसाठी सातत्याने संशोधन होत असून, त्यातील प्रत्येक यशाने आपण कृत्रिम अन्ननिर्मितीकडे जाणार आहोत. भविष्यामध्ये कदाचित आपल्याला खाद्याच्या निर्मितीसाठी वनस्पतीवरही अवलंबावे लागणार नाही, असे दिसते. सध्या या संशोधकांचे ध्येय केवळ इंधन निर्मिती इतकेच असले तरी त्यापुढेही पाहण्यास हरकत नाही.

संशोधकांना शुभेच्छा, त्यांच्या यशातच मानवाचे हित सामावलेले असणार आहे.

- सतीश कुलकर्णी

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Nanowires give 'solar fuel cell' efficiency a tenfold boost

Nanowires give 'solar fuel cell' efficiency a tenfold boost | Amazing Science |

Researchers make important step towards a solar cell that generates hydrogen.

Researchers have developed a very promising prototype of a new solar celll. The material gallium phosphide enables their solar cell to produce the clean fuel hydrogen gas from liquid water. Processing the gallium phosphide in the form of very small nanowires is novel and helps to boost the yield by a factor of ten. And does so using ten thousand times less precious material.

According to Bakkers, it's not simply about the yield -- where there is still a lot of scope for improvement he points out: "For the nanowires we needed ten thousand less precious GaP material than in cells with a flat surface. That makes these kinds of cells potentially a great deal cheaper," Bakkers says. "In addition, GaP is also able to extract oxygen from the water -- so you then actually have a fuel cell in which you can temporarily store your solar energy. In short, for a solar fuels future we cannot ignore gallium phosphide any longer."

GaP has good electrical properties but the drawback that it cannot easily absorb light when it is a large flat surface as used in GaP solar cells. The researchers have overcome this problem by making a grid of very small GaP nanowires, measuring five hundred nanometers (a millionth of a millimeter) long and ninety nanometers thick. This immediately boosted the yield of hydrogen by a factor of ten to 2.9 percent. A record for GaP cells, even though this is still some way off the fifteen percent achieved by silicon cells coupled to a battery.

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Water splitter produces clean-burning hydrogen fuel 24/7

Water splitter produces clean-burning hydrogen fuel 24/7 | Amazing Science |

In an engineering first, Stanford University scientists have invented a low-cost water splitter that uses a single catalyst to produce both hydrogen and oxygen gas 24 hours a day, seven days a week. The researchers believe that the device, described in anopen-access study published today (June 23) in Nature Communications, could provide a renewable source of clean-burning hydrogen fuel for transportation and industry.

“We have developed a low-voltage, single-catalyst water splitter that continuously generates hydrogen and oxygen for more than 200 hours, an exciting world-record performance,” said study co-author Yi Cui, an associate professor of materials science and engineering at Stanford and of photon science at the SLAC National Accelerator Laboratory.

Hydrogen has long been promoted as an emissions-free alternative to gasoline. But most commercial-grade hydrogen is made from natural gas — a fossil fuel that contributes to global warming. So scientists have been trying to develop a cheap and efficient way to extract pure hydrogen from water.

A conventional water-splitting device consists of two electrodes submerged in a water-based electrolyte. A low-voltage current applied to the electrodes drives a catalytic reaction that separates molecules of H2O, releasing bubbles of hydrogen on one electrode and oxygen on the other.

In these devices, each electrode is embedded with a different catalyst, typically platinum and iridium, two rare and costly metals. But in 2014, Stanford chemist Hongjie Dai developed a water splitter made of inexpensive nickel and iron that runs on an ordinary 1.5-volt battery.

In conventional water splitters, the hydrogen and oxygen catalysts often require different electrolytes with different pH — one acidic, one alkaline — to remain stable and active. “For practical water splitting, an expensive barrier is needed to separate the two electrolytes, adding to the cost of the device,” Wang explained.

“Our water splitter is unique because we only use one catalyst, nickel-iron oxide, for both electrodes,” said graduate student Haotian Wang, lead author of the study. “This bi-functional catalyst can split water continuously for more than a week with a steady input of just 1.5 volts of electricity. That’s an unprecedented water-splitting efficiency of 82 percent at room temperature.”

Wang and his colleagues discovered that nickel-iron oxide, which is cheap and easy to produce, is actually more stable than some commercial catalysts made of expensive precious metals. The key to making a single catalyst possible was to use lithium ions to chemically break the metal oxide catalyst into smaller and smaller pieces. That “increases its surface area and exposes lots of ultra-small, interconnected grain boundaries that become active sites for the water-splitting catalytic reaction,” Cui said. “This process creates tiny particles that are strongly connected, so the catalyst has very good electrical conductivity and stability.”

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Here Is the World's First Engine Driven by Nothing But Evaporation - Hygroscopy-driven Artificial Muscles

Here Is the World's First Engine Driven by Nothing But Evaporation - Hygroscopy-driven Artificial Muscles | Amazing Science |

Bioengineers invent a way to harvest energy from water evaporating at room temperature. It's an engine with living parts.

It might not look like much, but this plastic box is a fully functioning engine—and one that does something no other engine has ever done before. Pulling energy seemingly out of thin air, it harvests power from the ambient evaporation of room-temperature water. No kidding.

A team of bioengineers led by Ozgur Sahin at Columbia University have just created the world's first evaporation-driven engine, which they report today in the journalNature Communications. Using nothing more than a puddle of resting water, the engine, which measures less than four inches on each side, can power LED lights and even drive a miniature car. Better yet, Sahin says, the engine costs less than $5 to build.

"This is a very, very impressive breakthrough," says Peter Fratzl, a biomaterial researcher at the Max-Planck Institute of Colloids and Interfaces in Potsdam, Germany who was not involved in the research. "The engine is essentially harvesting useful amounts of energy from the infinitely small and naturally occurring gradients [in temperature] near the surface of water. These tiny temperature gradients exist everywhere, even in some of the most remote places on Earth."

To understand how the engine works, it helps to understand unique material behind it. The key to Sahin's astonishing new invention is a new material that Sahin calls HYDRAs (short for hygroscopy-driven artificial muscles). HYDRAs are essentially thin, muscle-like plastic bands that contract and expand with tiny changes in humidity. A pinky finger-length HYDRA band can cycle through contraction and expansion more than a million times with only a slight, and almost negligible, degradation of the material. "And HYDRAs change shape in really quite a dramatic way: they can almost quadruple in length," Sahin says.

Nicole Masureik's curator insight, June 17, 2:58 AM

Wow! Imagine a world powered by HYDRAs, rather than fossil fuels!

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Scientists use shape-fixing nanoreactor to make a better fuel cell catalyst

Scientists use shape-fixing nanoreactor to make a better fuel cell catalyst | Amazing Science |
Proton-exchange membrane fuel cells (PEMFCs) are lightweight fuel cells being developed for applications in vehicles and portable electronics. One of the biggest challenges facing their development is the need for expensive platinum-based catalysts. In an effort to lower the cost, scientists are looking for ways to either reduce the amount of platinum required or completely replace the platinum with a less expensive material. But so far, alternative materials have not performed nearly as well as platinum, mainly because they have fewer and less accessible "active sites"—locations where the catalyzed reactions can occur.

To address this challenge, scientists in a new study have developed a way to synthesize materials with a large number of active sites that also ensures that the active sites are accessible to all of the species (electrons, protons, oxygen, and water molecules, etc.) involved in the reactions. They've done this by synthesizing highly porous carbon nanomaterials, in which the pores act as open channels to transport various species to their particular active sites within the carbon framework.

The resulting catalyst, when incorporated into a PEMFC, has a peak power (600 mW/cm2) that is among the best of the non-platinum, non-precious-metal catalysts developed to date. In addition, the researchers explain that the method stands out because it produces the catalysts at a higher yield than any other previous method, in which most products are lost at high temperatures.

The researchers, led by Zidong Wei, Professor of Chemistry at Chongqing University in China, have published their work on the new PEMFC catalyst in a recent issue of the Journal of the American Chemical SocietyThe researchers describe the new high-yield method as "shape fixing" because it allows for the construction ofcarbon nanomaterials with a similar structure and morphology as their polymer precursors. The process of shape-fixing involves pouring a supersaturated sodium chloride (NaCl) solution onto a 3D polyaniline (PANI) carbon-based polymer in a beaker, which results in the water evaporating and NaCl recrystallizing around the PANI until the PANI is fully covered by crystals, almost appearing as if it is buried in a block of ice.

Because the NaCl fully seals the PANI, the researchers explain that the NaCl can be thought of as a nanoreactor. Inside this nanoreactor, the PANI is heated in the processes of pyrolysis and gasification, while various raw materials are added. In the end, the gasification of the various materials in the enclosed space causes the formation of many pores, and the carbonized PANI retains its original 3D shape due to previously being shape-fixed by the NaCl crystal. Further, as the researchers explain, the active sites created in this method are especially highly active.

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Solar could meet California energy demand three to five times over around existing infrastructure

Solar could meet California energy demand three to five times over around existing infrastructure | Amazing Science |

Carnegie Science researchers have found that the amount of energy that could be generated from solar equipment constructed on and around existing infrastructure in California would exceed the state’s demand by up to five times.

“Integrating solar facilities into the urban and suburban environment causes the least amount of land-cover change and the lowest environmental impact,” according to Carnegie’s Rebecca R. Hernandez (now at University of California Berkley).

The team found that just over 8 percent of all of the terrestrial surfaces in California have been developed by humans, from cities and buildings to park spaces. Residential and commercial rooftops present plenty of opportunity for power generation through small- and utility-scale solar power installations, the team said. Other compatible opportunities are available in open urban spaces such as parks.

California has about 6.7 million acres (27, 286 square kilometers) of land that is compatible for photovoltaic solar construction and about 1.6 million acres (6,274 square kilometers) compatible for concentrating solar power. There is also an additional 13.8 million acres (55,733 square kilometers) that is potentially compatible for photovoltaic solar energy development with minimal environmental impact and 6.7 million acres (27,215 square kilometers) also potentially compatible for concentrating solar power development.

“Because of the value of locating solar power-generating operations near roads and existing transmission lines, our tool identifies potentially compatible sites that are not remote, showing that installations do not necessarily have to be located in deserts,” Hernandez said.

This study, published by Nature Climate Change, included two kinds of solar technologies: photovoltaics, which use semiconductors and are similar to the solar panels found in consumer electronics, and concentrating solar power, which uses enormous curved mirrors to focus the sun’s rays.

A mix of both options would be possible, the researchers suggest. They found that small- and utility-scale solar power could generate up to 15,000 terawatt-hours of energy per year using photovoltaic technology and 6,000 terawatt-hours of energy per year using concentrating solar power technology.

“As California works to meet requirements that 33 percent of retail electricity be provided by renewable sources by 2020 and that greenhouse-gas emissions be 80 percent below 1990 levels by 2050, our research can help policymakers, developers, and energy stakeholders make informed decisions,” said Chris Field, director of Carnegie’s Department of Global Ecology. “Furthermore, our findings have implications for other states and countries with similarly precious environmental resources and infrastructural constraints.”

Lauren Quincy's curator insight, March 20, 12:05 AM

Unit 4: Political Organization of Space 


This article is about California working on policies to create solar facilities integrated into urban and suburban environments. Doing this would have little environmental footprint and could create as much as 5 times more energy needed for the state. This transition to solar energy could help cut emissions by 80% by 2050. Studies include two kinds of solar technologies. Photovoltaics, which use semiconductors and are similar to the solar panels found in consumer electronics, and concentrating solar power, which uses enormous curved mirrors to focus the sun’s rays. Using these, California can use solar energy to provide environmentally friendly energy. 

This relates to unit 4 because it deals with political policies and their environmental footprint. The government is working toward creating a solution to help reduce green house gasses and lesses the environmental footprint. They are working to employ many solar panels in urban and suburban areas near roads and existing transmission lines. 

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Ultra high-efficiency concentrating solar cells move to the rooftop

Ultra high-efficiency concentrating solar cells move to the rooftop | Amazing Science |

Ultra-high-efficiency multi-junction solar cells similar to those used in space or electric utilities may now be possible on your rooftop thanks to a new microscale solar-concentration technology called concentrating photovoltaic (CPV)developed by an international team of researchers.

The new CPV systems use inexpensive optics to concentrate sunlight,” said Noel C. Giebink, assistant professor of electrical engineering, Penn State. “Current CPV systems are the size of billboards and have to be pointed very accurately to track the sun throughout the day. You can’t put a system like this on your roof.”

Fortunately, the falling cost of typical silicon solar cells — from about 20 percent for silicon to more than 40 percent with the new CPV — is making them a smaller and smaller fraction of the overall cost of solar electricity (which includes permitting, wiring, installation and maintenance).

To enable CPV on rooftops, the researchers combined miniaturized gallium-arsenide photovoltaic cells, 3D-printed plastic lens arrays, and a moveable focusing mechanism. That combination reduces the size, weight and cost of the CPV system, allowing it to be installed on the south-facing side of a building’s roof. They reported their results Thursday (Feb. 5) in Nature Communications.

“We partnered with colleagues at the University of Illinois because they are experts at making small, very efficient multi-junction solar cells,” said Giebink. “These cells are less than 1 square millimeter, made in large, parallel batches, and then an array of them is transferred onto a thin sheet of glass or plastic.” To focus sunlight on the array of cells, the researchers embedded them between a pair of 3D-printed plastic lenslet arrays. Each lenslet in the top array acts like a small magnifying glass and is matched to a lenslet in the bottom array that functions like a concave mirror. With each tiny solar cell located in the focus of this duo, sunlight is intensified more than 200 times. To track the Sun over the course of a day, the middle solar cell sheet slides laterally in between the two lenslet arrays.

Previous attempts at such translation-based tracking have only worked for about two hours a day because the focal point moves out of the plane of the solar cells, leading to loss of light and a drop in efficiency. By sandwiching the cells between the lenslet arrays, the researchers solved this problem and enabled efficient solar focusing for a full eight hour day with only about 1 centimeter of total movement needed for tracking.

To lubricate the sliding cell array and also improve transmission through the lenslet sandwich, they used an optical oil, which allows for small motors using a minimal amount of force for mechanical tracking. “The vision is that such a microtracking CPV panel could be placed on a roof in the same space as a traditional solar panel and generate a lot more power,” said Giebink. “The simplicity of this solution is really what gives it practical value.”

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Scientists find hydrogen production in an extremophile bacterium (Halanaerobium hydrogeninformans)

Scientists find hydrogen production in an extremophile bacterium (Halanaerobium hydrogeninformans) | Amazing Science |

Dr. Melanie Mormile, professor of biological sciences at Missouri S&T, and her team discovered the bacterium "Halanaerobium hydrogeninformans" in Soap Lake, Washington. It can "produce hydrogen under saline and alkaline conditions in amounts that rival genetically modified organisms," Mormile says.

"Usually, I tend to study the overall microbial ecology of extreme environments, but this particular bacterium has caught my attention," Mormile says. "I intend to study this isolate in greater detail."

Mormile, an expert in the microbial ecology of extreme environments, wasn't searching for a bacterium that could produce hydrogen. Instead, she first became interested in bacteria that could help clean up the environment, especially looking at the extremophiles found in Soap Lake.

An extremophile is a microorganism that lives in conditions of extreme temperature, acidity, alkalinity or chemical concentration. Living in such a hostile environment, "Halanaerobium hydrogeninformans" has metabolic capabilities under conditions that occur at some contaminated waste sites.

With "Halanaerobium hydrogeninformans," she expected to find an iron-reducing bacterium and describe a new species. What she found was a new species of bacterium that can produce hydrogen and 1, 3-propanediol under high pH and salinity conditions that might turn out to be valuable industrially. An organic compound, 1, 3-propenediol can be formulated into industrial products including composites, adhesives, laminates and coatings. It's also a solvent and can be used as antifreeze.

The infrastructure isn't in place now for hydrogen to replace gasoline as a fuel for planes, trains and automobiles. But if hydrogen becomes an alternative to gasoline, "Halanaerobium hydrogeniformans," mass-produced on an industrial scale, might be one solution – although it won't be a solution anytime soon.

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Space-Based Solar Power May Arrive Sooner Than You Think

Space-Based Solar Power May Arrive Sooner Than You Think | Amazing Science |

The idea of capturing solar power in space for use as energy on Earth has been around since the beginning of the space age. In the last few years, however, scientists around the globe -- and several researchers at the Energy Department’s own Lawrence Livermore National Laboratory (LLNL) -- have shown how recent technological developments could make this concept a reality.

On earth, solar power is greatly reduced by night, cloud cover, atmosphere and seasonality. Some 30 percent of all incoming solar radiation never makes it to ground level. In space the sun is always shining, the tilt of the Earth doesn't prevent the collection of power and there’s no atmosphere to reduce the intensity of the sun’s rays. This makes putting solar panels into space a tempting possibility. Additionally, SBSP can be used to get reliable and clean energy to people in remote communities around the world, without relying on the traditional grid to a large local power plant.

Self-assembling satellites are launched into space, along with reflectors and a microwave or laser power transmitter. Reflectors or inflatable mirrors spread over a vast swath of space, directing solar radiation onto solar panels. These panels convert solar power into either a microwave or a laser, and beam uninterrupted power down to Earth. On Earth, power-receiving stations collect the beam and add it to the electric grid. The two most commonly discussed designs for SBSP are a large, deeper space microwave transmitting satellite and a smaller, nearer laser transmitting satellite.

Microwave transmitting satellites orbit Earth in geostationary orbit (GEO), about 35,000 km above Earth’s surface. Designs for microwave transmitting satellites are massive, with solar reflectors spanning up to 3 km and weighing over 80,000 metric tons. They would be capable of generating multiple gigawatts of power, enough to power a major U.S. city. The long wavelength of the microwave requires a long antenna, and allows power to be beamed through the Earth’s atmosphere, rain or shine, at safe, low intensity levels hardly stronger than the midday sun. Birds and planes wouldn’t notice much of anything flying across their paths.

The estimated cost of launching, assembling and operating a microwave-equipped GEO satellite is in the tens of billions of dollars. It would likely require as many as 40 launches for all necessary materials to reach space. On Earth, the rectenna used for collecting the microwave beam would be anywhere between 3 and 10 km in diameter, a huge area of land, and a challenge to purchase and develop.

Laser transmitting satellites, as described by our friends at LLNL, orbit in low Earth orbit (LEO) at about 400 km above the Earth’s surface. Weighing in in at less than 10 metric tons, this satellite is a fraction of the weight of its microwave counterpart. This design is cheaper too; some predict that a laser-equipped SBSP satellite would cost nearly $500 million to launch and operate. It would be possible to launch the entire self-assembling satellite in a single rocket, drastically reducing the cost and time to production. Also, by using a laser transmitter, the beam will only be about 2 meters in diameter, instead of several km, a drastic and important reduction.

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How to store solar energy more cost-effectively for use at night

How to store solar energy more cost-effectively for use at night | Amazing Science |

There’s currently no cost-effective, large-scale way to store solar energy, but Stanford researchers have developed a solution: using electrolysis to turn tanks of water and hydrogen into batteries. During the day, electricity from solar cells could be used to break apart water into hydrogen and oxygen. Recombining these gases would generate electricity for use at night.

There’s one major problem. Electrolysis uses electricity to crack the chemical bonds that hold H2O together. Cracking the chemical bonds of water produces a hydrogen ion — a proton with no electron to balance it out. A good H2 catalyst gives the proton a place to stick until it can pick up an electron to form a hydrogen atom on the catalyst surface and then pair up with a neighboring hydrogen atom to bubble off as H2.

The trick is finding a catalyst with the right stickiness. “If the binding is too weak, the ions don’t stick,” said chemical engineering Professor Thomas Jaramillo. “If it’s too strong, they never get released.” Platinum is perfect, but pricey. Last year the Stanford engineers discovered that a version of molybdenum sulfide called molybdenum phosphosulfide, a catalyst widely used in petrochemical processing, had some of the right properties, with an efficiency approaching that of platinum, to serve as a cheap but efficient alternative to platinum, as described in the German scientific journal Angewandte Chemie.

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Hybrid solar cells convert both light and heat from sun's rays into electricity

Hybrid solar cells convert both light and heat from sun's rays into electricity | Amazing Science |

Solar cells today are getting better at converting sunlight to electricity, but commercial panels still harvest only part of the radiation they're exposed to. Scientists are working to change this using various methods. One approach is to hybridize solar cells with different materials to capture more of the sun's energy.

Eunkyoung Kim and colleagues turned to a clear, conductive polymer known as PEDOT to try to accomplish this. The researchers layered a dye-sensitized solar cell on top of a PEDOT film, which heats up in response to light. Below that, they added a pyroelectric thin film and a thermoelectric device, both of which convert heat into electricity. The efficiency of all components working together was more than 20 percent higher than the solar cell alone. With that boost, the system could operate an LED lamp and an electrochromic display.

Via Mariaschnee
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Microalgae Biofuels Market Rapidly Grows

Microalgae Biofuels Market Rapidly Grows | Amazing Science |

Algae, which causes a lot of damage to the marine ecosystem by creating water blooms and red tides, is now turning into the next-generation raw material of eco-friendly biofuels, including biodiesel and bioethanol.

Until now, biofuels have been produced from first-generation grass feed stock, such as corn and sugar cane, or second-generation plant feed stock, including corn stalk and rice husks. However, using grass feed stock aggravates shortages of food among low-income groups by raising the price of grain, while plant feed stock has limitations like low yields. As a third-generation raw material that will overcome such weak points, marine algae and microalgae are in the spotlight from the global biofuels industry.

In particular, they absorb carbon dioxide in the process of growth. So, when marine algae and microalgae are provided carbon dioxide emitted from thermal power plants and breweries, they can reduce carbon dioxide emissions and produce biofuels at the same time. According to a survey, 180 tons of carbon dioxide are decreased when producing 100 tons of microalgae.

Sohn Jong-koo, senior researcher at the Industry Information Analysis Center at KISTI, said, “Currently, the U.S. accounts for 50 percent of the algae biofuel market, while Europe accounts for 30 percent. Korea, Japan, China, Australia and Israel are now going after them.” Sohn expects that the related market will be created in earnest, beginning this year, as commercial plants will be constructed in earnest. In fact, market research firm Pike Research has forecasted that the algae biofuel market this year will be estimated at US$1.6 billion (1.88 trillion won), and it will rapidly grow by 812 percent in the next five years to reach US$13 billion (15.3 trillion won) in 2020. It means that 61 million gallons, or 230 million liters, of algae biofuels will be sold around the world five years after that.

In a bid to tap into such a huge market, South Korean government-funded research institutes and private firms are advancing technology based on government-level support. The country is aiming to construct 500,000 hectares of marine algae farms by 2020 and produce 227 million liters of bioethanol annually, taking over 20 percent of domestic gasoline consumption.

Via Marko Dolinar
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Transparent lithium-ion battery that recharges via the sun demonstrated

Transparent lithium-ion battery that recharges via the sun demonstrated | Amazing Science |
A team of researchers with Kogakuin University has demonstrated a lithium ion battery which is not only nearly transparent, but can also be recharged with direct sunlight alone. The battery was demonstrated at Innovation Japan 2015, where the leader of the team, and president of the university explained the goals of their battery research and the benefits consumers might eventually see from it.

It was just four years ago that a team of researchers at Stanford unveiled a nearly transparent lithium-ion battery that was both see-through and bendable. The team in Japan has been working with the new technology since then, two years ago unveiling a nearly transparent battery of their own which was charged with a separate solar panel. Now, the team has upgraded that battery by allowing it to recharge itself when exposed to sunlight.

To make the new battery, the team tweaked the materials that were already in use—lithium iron phosphate for the positive electrode and lithium titanate and lithium hexafluorophosphate for the negative electrode—all ingredients that are already generally used to make lithium-ion batteries. When the battery is exposed to sunlight, it becomes slightly tinted (down to approximately 30 percent transmittance), lowering the amount of light that can pass through. The trick in getting them to be nearly transparent is in making them really thin—the electrodes are just 80nm and 90nm. After discharge, the team reports that light transmittance rises to approximately 60 percent. They also report output from the battery of 3.6V.

The team believes their transparent solar charged batteries could one day be used as "smart" windows for homes or offices, allowing for not only automatic tinting, but as energy capture and storage devices for use in a variety of ways. Taking the concept further, it is possible the idea could be extended at some point to consumer electronics, with displays or even entire casings made of the material to help keep phones, tablets and other gear operating when used outdoors or under other types of lighting. But first the new technology will have to be vetted to make sure it works as promised (it has been tested at 20 charge/discharges) and then to see if it can stand up to the rigors of daily use.

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Making hydrogen fuel from water and visible light at 100 times higher efficiency

Making hydrogen fuel from water and visible light at 100 times higher efficiency | Amazing Science |

A big step closer to hydrogen as a practical fuel to power vehicles and electrical devices.

Researchers at Michigan Technological University have found a way to convert light to hydrogen fuel more efficiently — a big step closer to mimicking photosynthesisCurrent methods for creating hydrogen fuel are based on using electrodes made from titanium dioxide (TiO2), which acts as a catalyst to stimulate the light–>water–>hydrogen chemical reaction. This works great with ultraviolet (UV) light, but UV comprises only about 4% of the total solar energy, making the overall process highly inefficient.*

The ideal would be to use visible light, since it constitutes about 45 percent of solar energy. Now two Michigan Tech scientists — Yun Hang Hu, the Charles and Carroll McArthur professor of Materials Science and Engineer, and his PhD student, Bing Han — have developed a way to do exactly that.

They report in Journal of Physical Chemistry that by absorbing the entire visible light spectrum, they have increased the yield and energy efficiency of creating hydrogen fuel by up to two magnitudes (100 times) greater than previously reported.

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New nanogenerator harvests power from rolling tires

New nanogenerator harvests power from rolling tires | Amazing Science |
A group of University of Wisconsin-Madison engineers and a collaborator from China have developed a nanogenerator that harvests energy from a car's rolling tire friction.

An innovative method of reusing energy, the nanogenerator ultimately could provide automobile manufacturers a new way to squeeze greater efficiency out of their vehicles.

The researchers reported their development, which is the first of its kind, in a paper published May 6, 2015, in the journal Nano Energy.

Xudong Wang, the Harvey D. Spangler fellow and an associate professor of materials science and engineering at UW-Madison, and his PhD student Yanchao Mao have been working on this device for about a year.

The nanogenerator relies on the triboelectric effect to harness energy from the changing electric potential between the pavement and a vehicle's wheels. The triboelectric effect is the electric charge that results from the contact or rubbing together of two dissimilar objects. Wang says the nanogenerator provides an excellent way to take advantage of energy that is usually lost due to friction.

"The friction between the tire and the ground consumes about 10 percent of a vehicle's fuel," he says. "That energy is wasted. So if we can convert that energy, it could give us very good improvement in fuel efficiency." The nanogenerator relies on an electrode integrated into a segment of the tire. When this part of the tire surface comes into contact with the ground, the friction between those two surfaces ultimately produces an electrical charge-a type of contact electrification known as the triboelectric effect.

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Chemists devise technology that could transform solar energy storage from microseconds to weeks

Chemists devise technology that could transform solar energy storage from microseconds to weeks | Amazing Science |

A new technology developed by chemists at UCLA is capable of storing solar energy for up to several weeks. 

The materials in most of today’s residential rooftop solar panels can store energy from the sun for only a few microseconds at a time. A new technology developed by chemists at UCLA is capable of storing solar energy for up to several weeks — an advance that could change the way scientists think about designing solar cells.

The findings are published June 19 in the journal Science. The new design is inspired by the way that plants generate energy through photosynthesis.

“Biology does a very good job of creating energy from sunlight,” said Sarah Tolbert, a UCLA professor of chemistry and one of the senior authors of the research. “Plants do this through photosynthesis with extremely high efficiency.”

“In photosynthesis, plants that are exposed to sunlight use carefully organized nanoscale structures within their cells to rapidly separate charges — pulling electrons away from the positively charged molecule that is left behind, and keeping positive and negative charges separated,” Tolbert said. “That separation is the key to making the process so efficient.”

To capture energy from sunlight, conventional rooftop solar cells use silicon, a fairly expensive material.  There is currently a big push to make lower-cost solar cells using plastics, rather than silicon, but today’s plastic solar cells are relatively inefficient, in large part because the separated positive and negative electric charges often recombine before they can become electrical energy.

“Modern plastic solar cells don’t have well-defined structures like plants do because we never knew how to make them before,” Tolbert said. “But this new system pulls charges apart and keeps them separated for days, or even weeks. Once you make the right structure, you can vastly improve the retention of energy.”

The two components that make the UCLA-developed system work are a polymer donor and a nano-scale fullerene acceptor. The polymer donor absorbs sunlight and passes electrons to the fullerene acceptor; the process generates electrical energy.

The plastic materials, called organic photovoltaics, are typically organized like a plate of cooked pasta — a disorganized mass of long, skinny polymer “spaghetti” with random fullerene “meatballs.” But this arrangement makes it difficult to get current out of the cell because the electrons sometimes hop back to the polymer spaghetti and are lost.

The UCLA technology arranges the elements more neatly — like small bundles of uncooked spaghetti with precisely placed meatballs. Some fullerene meatballs are designed to sit inside the spaghetti bundles, but others are forced to stay on the outside.  The fullerenes inside the structure take electrons from the polymers and toss them to the outside fullerene, which can effectively keep the electrons away from the polymer for weeks.

Ra's curator insight, June 23, 5:27 PM

"A new technology developed by chemists at UCLA is capable of storing solar energy for up to several weeks."

changes to solar panel construction that could do away with the need for bulky battery storage or any connection to the grid. Rural camp site looking brighter, although maybe somewhere in the future. 

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Engineers develop state-by-state plan to convert US to 100% clean, renewable energy by 2050

Engineers develop state-by-state plan to convert US to 100% clean, renewable energy by 2050 | Amazing Science |
One potential way to combat ongoing climate change, eliminate air pollution mortality, create jobs and stabilize energy prices involves converting the world's entire energy infrastructure to run on clean, renewable energy.

This is a daunting challenge. But now, in a new study, Mark Z. Jacobson, a professor of civil and environmental engineering at Stanford, and colleagues, including U.C. Berkeley researcher Mark Delucchi, are the first to outline how each of the 50 states can achieve such a transition by 2050. The 50 individual state plans call for aggressive changes to both infrastructure and the ways we currently consume energy, but indicate that the conversion is technically and economically possible through the wide-scale implementation of existing technologies.

"The main barriers are social, political and getting industries to change. One way to overcome the barriers is to inform people about what is possible," said Jacobson, who is also a senior fellow at the Stanford Woods Institute for the Environment and at the Precourt Institute for Energy. "By showing that it's technologically and economically possible, this study could reduce the barriers to a large scale transformation."

The study is published in the online edition of Energy and Environmental Sciences. An interactive map summarizing the plans for each state is available at

Jacobson and his colleagues started by taking a close look at the current energy demands of each state, and how those demands would change under business-as-usual conditions by the year 2050. To create a full picture of energy use in each state, they examined energy usage in four sectors: residential, commercial, industrial and transportation.

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Audi Has Made Diesel From Water And Carbon Dioxide

Audi Has Made Diesel From Water And Carbon Dioxide | Amazing Science |

It’s the holy grail in energy production: produce a fuel that is both carbon neutral and can be poured directly into our current cars without the need to retrofit. There are scores of companies out there trying to do just that using vegetable oil, algae, and even the microbes found in panda poop to turn bamboo into fuel.

This week, German car manufacturer Audi has declared that they have been able to create an "e-diesel," or diesel containing ethanol, by using renewable energy to produce a liquid fuel from nothing more than water and carbon dioxide. After a commissioning phase of just four months, the plant in Dresden operated by clean tech company Sunfire has managed to produce its first batch of what they’re calling “blue crude.” The product liquid is composed of long-chain hydrocarbon compounds, similar to fossil fuels, but free from sulfur and aromatics and therefore burns soot-free.

The first step in the process involves harnessing renewable energy through solar, wind or hydropower. This energy is then used to heat water to temperatures in excess of 800˚C (1472˚F). The steam is then broken down into oxygen and hydrogen through high temperature electrolysis, a process where an electric current is passed through a solution.

The hydrogen is then removed and mixed with carbon monoxide under high heat and pressure, creating a hydrocarbon product they’re calling "blue crude." Sunfire claim that the synthetic fuel is not only more environmentally friendly than fossil fuel, but that the efficiency of the overall process—from renewable power to liquid hydrocarbon—is very high at around 70%. The e-diesel can then be either mixed with regular diesel, or used as a fuel in its own right.

But all may not be as it seems. The process used by Audi is actually called the Fischer-Tropsch process and has been known by scientists since the 1920s. It was even used by the Germans to turn coal into diesel during the Second World War when fuel supplies ran short. The process is currently used by many different companies all around the world, especially in countries where reserves of oil are low but reserves of other fossils fuels, such as gas and coal, are high.

And it would seem that Audi aren’t the first to think about using biogas facilities to produce carbon neutral biofuels either. Another German company called Choren has already made an attempt at producing biofuel using biogas and the Fischer-Tropsch process. Backed by Shell and Volkswagen, the company had all the support and funding it needed, but in 2011 it filed for bankruptcy due to impracticalities in the process.

Audi readily admits that none of the processes they use are new, but claim it’s how they’re going about it that is. They say that increasing the temperature at which the water is split increases the efficiency of the process and that the waste heat can then be recovered. Whilst their announcement might not be heralding a new fossil fuel-free era, the tech of turning green power into synthetic fuel could have applications as a battery to store excess energy produced by renewables.

Daniel Lindahl's curator insight, May 25, 1:47 PM

Audi has successfully made a clean, carbon neutral form of diesel fuel known as "e-diesel". This will drastically change cars and fuel research in the future. Developments like these show the growth and change of industry as a whole. 

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Scientists using sunlight and artificially make liquid fuel

Scientists using sunlight and artificially make liquid fuel | Amazing Science |

The process could one day produce an energy source that is carbon neutral and avoids the pitfalls of biofuels.

Daniel Nocera became an instant celebrity in renewable energy circles in 2011 when he invented the artificial leaf. More an idea than an actual leaf, the Harvard professor came up with a way to harness sunlight with silicon to split water into oxygen and hydrogen. From there, it was theorized, it was just a step further to create hydrogen fuel cells. It seemed too good to be true. Finally, someone had found a way to use the power of the sun to produce a clean fuel source. But there was a slight problem. The infrastructure for a hydrogen-fueled economy didn't exist then and, to this day, still is nowhere close to becoming a reality.

So, Nocera went back to the drawing board. Taking his artificial leaf idea, he teamed up with several other researchers at Harvard including Jeffery Way and Pamela Silver. They took the hydrogen from the photovoltaic cells of the artificial leaf and fed it to the soil bacterium Ralstonia eutropha. The microbe combined the hydrogen with carbon dioxide from another source and, for the first time, produced liquid fuel.

"This is sort of the next step moving beyond hydrogen to make a fuel that is integratable with our current infrastructure," Nocera, a co-author on a study that appeared in the journal Proceedings of the National Academy of Sciences.  "I can't convince an entire society to change over their infrastructure to use hydrogen," he said. "Instead of fighting it, this is sort of going with the flow to so speak."

But while thrilled with his team's discovery, Nocera admitted they still face a challenge of improving the efficiency of the process so that fuel could be produced commercially. Currently, they are only able to convert 1 percent of the sunlight into liquid fuel, which falls far short of the 10 percent efficiency needed to establish a viable, sustainable solar fuel industry.

Nocera is part of a band of scientists trying to crack the nut that is solar fuels. If successful, they would produce a fuel that gives the United States energy independence, helps combat global warming by finding a replacement for fossil fuels and avoids the concerns of biofuels, which often compete with food for land.

Among those investing heavily in solar fuel technology is the Department of Energy, which is spending $1.22 million over five years on the Joint Center for Artificial Photosynthesis. Since 2010, the center has been the nation's largest research program dedicated to the development of an artificial solar-fuel generation technology. But it was another DOE program that helped inspire the latest breakthrough. Called the electrofuels program at the DOE's Advanced Research Projects Agency, it is tasked with using microorganisms to create liquid fuel for transportation. Out of the program came the microbe used in the latest research to produce liquid fuel.

"The idea was, could you take a bug like Ralstonia eutropha and mess around with its guts, do a bunch of genetic engineering so that bug will take hydrogen, carbon dioxide and make liquid fuel," said Eric J. Toone, who founded the electrofuels program but is now the director of the Duke Innovation and Entrepreneurship Initiative.

Ken Matsumoto's curator insight, March 26, 7:20 AM

David Nocera has teamed up with several other researchers at Harvard to convert sunlight into liquid fuel. They have currently succeeded in converting 1 percent of the sunlight but need 10 times the amount to establish a sustainable solar fuel industry. 

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Making Bioethanol: Is a U.S. Biorefinery Industry Emerging?

Making Bioethanol: Is a U.S. Biorefinery Industry Emerging? | Amazing Science |

For decades, Brazil and the United States were the major countries producing biofuels.In Brazil, sugarcane was the raw material and ethanol producers simply fermented the extracted sugars. The spent cane (bagasse) was fed into solid fuel boilers to produce steam and power, and the excess was sold as bedding or became waste. In the United States, corn was the raw material; the starch was converted to sugar and fermented. Dried distillers grain was a by-product and was sold as animal feed. The cornhusks and stover were usually left in the fields to maintain soil fertility and structure. Most U.S. corn ethanol producers used natural gas to supply process heat. Sugarcane and corn for both processesis renewable.

Corn ethanol has been criticized for inefficiency and for not being sustainable. The industry is improving land use by increasing yield, gaining 30 to 50 percent yield through using spent crops. Energy required per gallon has decreased from 37,000 BTU per gallon in 1994 to 23,862 BTU per gallon in 2012. Similar gains have been made in reducing water consumption. As industries mature, they typically become more efficient. In the United States, corn ethanol may not have been the best gasoline replacement, but it has brought significant benefits. In particular, it became a profitable, commercial business segment with steady employment that provided financial benefit to farmers, helped lower the price of gasoline by about a dollar per gallon, deferred the importation of about 450 million barrels of oil in 2013, and helped the U.S. balance of trade by about $45 billion annually.

The 85 million gallon annual cellulosic ethanol capacity is dominated by the agriculture community, which is making significant commercial progress through working with farmers, agronomists and harvesting equipment suppliers to achieve low-cost, sustainable feedstocks.

A variety of technical approaches have been developed, and more are emerging to improve the economics of operations:

POET-DSM Advanced Biofuels, which held a grand opening in September 2014 in Emmetsburg, Iowa, will produce 20 million annual gallons (growing to 25 million) of cellulosic ethanol from corn stover. The plant is located adjacent to a POET 55 million annual gallon corn ethanol plant. The stover feedstock is gathered after corn harvest. Seventy-five percent of the corn crop residue is left in the field, which studies have shown is sufficient to maintain soil fertility. The smaller size for the cellulosic ethanol plant was selected in part to be able to gather biomass from a nominal 45-mile radius. The process for the corn stover after harvest involves pretreatment, enzymatic hydrolysis to sugars, fermentation to ethanol and, finally, distillation. The effluent stream from the cellulosic plant is sent to an anaerobic digester to produce biogas that is used in both plants. The solid stream of lignin is burned in a solid fuel boiler to produce steam for both plants.

In Hugoton, Kansas, Abengoa will produce 25 million annual gallons of cellulosic ethanol and 18 megawatts (MW) of power from wheat straw and agricultural waste. The process is similar to that of POET-DSM. Residuals are sent to a solid fuel boiler to produce process heat and power. At the time of writing, DuPont was slated to start up a 29 million annual gallon cellulosic ethanol plant from corn stover in Nevada, Iowa, in late 2014. The process will be similar to the two described above.

INEOS Bio, based in Vero Beach, Fla., has eliminated forest waste as a feedstock and is supplementing citrus waste with sorted municipal solid waste (SMSW); they will continue to make 8 million annual gallons of cellulosic ethanol and generate 6 MW of power. The process includes pretreatment, gasification, syngas cleanup, anaerobic fermentation to ethanol and distillation. Steam recovered from the gasification/cleanup stage is passed through a turbine to generate power, and the extracted steam from the turbine is used for process heat.

Quad County Corn Processors is producing 2 million gallons of cellulosic ethanol per year using corn kernel cellulose (a corn fiber waste product) as feedstock. The corn kernel cellulose is a byproduct of the firm’s 35 million gallon per year corn ethanol plant. Quad County invented and patented Cellerate technology and recently granted Syngenta an exclusive license to market the process to other ethanol plants in the United States and Canada. Cellerate technology has the ability to generate 1 billion gallons of additional ethanol by adding the bolt-on technology to the existing dry grind ethanol plants without using any more corn.

In Alpena, Mich., American Process, Inc. (API) is producing about 1 million annual gallons of cellulosic ethanol per year from the hemicellulose in the effluent obtained from an adjacent hardboard mill. The mill washes its fiber to remove some hemicellulose to prevent the hardboard sticking to the plates during hot pressing. Previously, these hemicellulose materials wound up in the mill’s effluent stream. BDC maintains metrics on these and other plants and can estimate capital cost, operating cost, time to construct, federal and state incentives and details about technology and commercial potential.

Documented progress is also occurring outside the United States as well as in emerging facilities within the U.S.:

Beta Renewables established a 12 million annual gallon cellulosic ethanol facility in Italy, licensed a second plant in Brazil (Gran Bio) and is licensing its third and fourth plants in North Carolina and the Slovak Republic.

GranBio in Brazil is producing 21.6 million annual gallons of cellulosic ethanol from bagasse using the Beta Renewables technology.

Enerkem, in Alberta, Canada, is producing 10 million annual gallons of bio-methanol from SMSW.

Fiberight, in Iowa, is restarting 6 million annual gallons of cellulosic ethanol from SMSW and paper mill sludge.

Dong Energy in Denmark has a demonstration plant with a capacity of 0.8 tons of cellulosic ethanol and 1.5 tons of bio-pellets per hour. If the plant were to run full time this would amount to 1.8 million gallons of cellulosic ethanol and 13,000 tonnes of biopellets per year.

Husky Energy in Alberta, Canada, is very interesting because it captures and sells or uses 250 tons of CO2 from its corn ethanol fermenters.

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Energy-Harvesting Piezoelectric Flags

Energy-Harvesting Piezoelectric Flags | Amazing Science |

The movement of a flag made of piezoelectric elements could be used to convert the wind’s mechanical energy into electrical power. In a steady wind flow, instabilities arising from the flag-wind interaction can lead to self-sustained flapping, which generates current in a coupled output circuit, as shown by a number of recent studies. However, the design of an optimal circuit remains a challenge: The circuit can induce a feedback coupling to the piezoelectric material, which, under some conditions, hinders flapping and lowers device efficiency. Yifan Xia, from École Polytechnique, France, and colleagues have now calculated that with an optimized resonant circuit, stable flapping motion, robust to velocity fluctuations, can be achieved at lower flow velocities than in previous studies. The scheme could open the way to efficient piezoelectric technologies that can harvest energy from a wide range of fluids (wind, tides, rivers, etc.)

The authors modeled a simple plane flag covered on both surfaces with piezoelectric patches and connected to a resonant circuit containing inductive and resistive elements. They found that when the flapping frequency was close to the natural frequency of the circuit, the two frequencies locked-in and the whole system resonated. By proper choice of the circuit’s frequency, the amplitude of the flapping and the energy output could be maximized. The frequency lock-in had two other advantages. First, it made flapping and energy harvest more robust: Small fluid velocity fluctuations, which could have shifted the flapping frequency, making it unstable, had little effect. Second, flapping could be induced at lower fluid velocities, at which the flag otherwise would not have flapped, extending the wind-velocity range suitable for energy harvesting.

This research is published in Physical Review Applied.

Laurent RUEL's curator insight, February 25, 5:25 AM

extra power for free for all static consuming units in telecom, ...

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Stanford engineers invent high-tech mirror to beam heat away from buildings into space

Stanford engineers invent high-tech mirror to beam heat away from buildings into space | Amazing Science |

Stanford engineers have invented a revolutionary coating material that can help cool buildings, even on sunny days, by radiating heat away from the buildings and sending it directly into space. A team led by electrical engineering ProfessorShanhui Fan and research associate Aaswath Raman reported this energy-saving breakthrough in the journal Nature.

The heart of the invention is an ultrathin, multilayered material that deals with light, both invisible and visible, in a new way. Invisible light in the form of infrared radiation is one of the ways that all objects and living things throw off heat. When we stand in front of a closed oven without touching it, the heat we feel is infrared light. This invisible, heat-bearing light is what the Stanford invention shunts away from buildings and sends into space.

Of course, sunshine also warms buildings. The new material, in addition dealing with infrared light, is also a stunningly efficient mirror that reflects virtually all of the incoming sunlight that strikes it. The result is what the Stanford team calls photonic radiative cooling – a one-two punch that offloads infrared heat from within a building while also reflecting the sunlight that would otherwise warm it up. The result is cooler buildings that require less air conditioning.

"This is very novel and an extraordinarily simple idea," said Eli Yablonovitch, a professor of engineering at the University of California, Berkeley, and a pioneer of photonics who directs the Center for Energy Efficient Electronics Science. "As a result of professor Fan's work, we can now [use radiative cooling], not only at night but counter-intuitively in the daytime as well."

The researchers say they designed the material to be cost-effective for large-scale deployment on building rooftops. Though still a young technology, they believe it could one day reduce demand for electricity. As much as 15 percent of the energy used in buildings in the United States is spent powering air conditioning systems.

In practice the researchers think the coating might be sprayed on a more solid material to make it suitable for withstanding the elements.

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