Plasmonic device converts light into electricity

By Lisa Zyga

Surface plasmons on the top electrode in the MIM device can increase the current from the top electrode so that it is greater than the current from the bottom electrode, generating a positive net current. Image credit: Wang and Melosh. ©2011 American Chemical Society

While the most common device for converting light into electricity may be photovoltaic (PV) solar cells, a variety of other devices can perform the same light-to-electricity conversion, such as solar-thermal collectors and rectennas. In a new study, engineers have designed a new device that can convert light of infrared (IR) and visible wavelengths into direct current by using surface plasmon excitations in a simple metal-insulator-metal (MIM) device.

The researchers, Fuming Wang and Nicholas A. Melosh of Stanford University, have published their study on the new device in a recent issue of Nano Letters. “The greatest significance thus far is to show an alternative method to rectennas and PV devices for IR and visible light conversion,” Melosh told PhysOrg.com. “The conversion efficiencies aren't amazingly high compared to a PV in visible, so it’s not going to replace PVs, but it could be used for energy scavenging later on.” The new device’s MIM architecture is similar to that of a rectenna. However, whereas rectennas operate with long-wavelength light such as microwaves and radio waves, the new device operates with a broad spectrum of infrared to visible wavelengths. When the MIM device is illuminated, incoming photons are absorbed by the top and bottom metal electrodes. Upon absorption, each photon excites an electron in the metal into a higher energy state so that it becomes a “hot electron.” About half of the hot electrons travel toward the metal-insulator interface, where they may be collected by the other electrode. However, photon absorption in the upper and lower electrodes generates currents with opposite signs, so a net DC current is achieved only if the absorption is larger at one electrode than the other.

Electron transmission in MIM devices (a) with and (b) without surface plasmon excitations. (c) The measured photocurrent in a device with surface plasmons (black line) is higher than in a device without them (red line). Image credit: Wang and Melosh. ©2011 American Chemical Society

This ability to maximize current from one electrode while minimizing it from the other is one of the biggest challenges for MIM devices. To do this, researchers can change the thicknesses of the electrodes. However, there is a tradeoff, since in a thicker electrode, more photons are absorbed but fewer electrons reach the interface due to increased scattering. Wang and Melosh’s solution is to use a prism to excite surface plamons (SPs) on the metal surface of the electrodes when under illumination. The SPs, which are small electron oscillations, can create a higher concentration of hot electrons in one electrode by efficiently coupling to light. The SP coupling efficiency depends on several factors, such as the thickness of the electrode, the type of metal used, and the wavelength of incoming light.

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Plasmonic device converts light into electricity
More information: Fuming Wang and Nicholas A. Melosh. “Plasmonic Energy Collection through Hot Carrier Extraction.” Nano Letters, DOI: 10.1021/nl203196z

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5 crazy inventions from the mind of Nikola Tesla

Earthquake machines! Death rays! Those far-fetched gadgets are part of a plan to build a museum dedicated to one of history's most famous mad scientists

Early 20th century inventor Nikola Tesla was ahead of his time with concepts that ranged from x-rays to robotics. Photo: Herbert Barraud/Getty Images

Nikola Tesla signature (Photo credit: Wikipedia)

Matthew Inman, proprietor of web comic The Oatmeal, is on a mission to build a crowd-funded museum dedicated to inventor Nikola Tesla, who Inman refers to as "the greatest geek who ever lived." Inman's goal was to raise $850,000 (which would be matched dollar-for-dollar by a New York state grant) in 45 days. But surprisingly, a little more than a week into it, the online campaign has gathered more than $1.1 million in donations. Many of the inventor's fans think Tesla was more brilliant than his more famous contemporaries, including Alexander Graham Bell and Thomas Edison. Even though Tesla isn't exactly a household name, his unsung accomplishments and wild imagination have turned him into something of a folk hero. Here, a rundown of five of Tesla's craziest inventions:

Wireless transmission of power and energy demonstration during his high frequency and potential lecture of 1891 (Photo credit: Wikipedia)

1. Wireless energy transfer
About 120 years ago at the 1893 World Fair in Chicago, Tesla demonstrated that you could wirelessly transmit electricity by firing up a series of phosphorous light bulbs in a process he called electrodynamic induction. He dreamed that such technology would allow us to one day shoot power over long distances in the atmosphere, supplying distant destinations with the energy needed to live comfortably. Now over a century later, companies such as Intel and Sony are interested in applying the non-radiative energy transfer to things such as cell phones to allow you to charge your battery without messy power cables.

2. X-raysTesla's research in the field of electromagnetism helped give radiologists everywhere the ability to peer into a person's anatomy without cutting them open — a concept that, in the late 1800s, sounded far-fetched. Although German physicist Willhelm Röntgen is widely credited with the discovery of X-rays in 1895, Tesla's own experiments with the technology eight years prior highlighted some of the inherent dangers of using radiation on human flesh.

3. Death ray
In the 1930s Tesla reportedly invented a particle beam weapon that some, ironically, called a "peace ray," says Lauren Davis at io9. "The device was, in theory, capable of generating an intense targeted beam of energy" that could be used to dispose of enemy warplanes, foreign armies, "or anything else you'd rather didn't exist." The so-called "death ray" was never constructed, however, even though Tesla shopped the device around to various military divisions. The plans for the laser were never found after Tesla's death.

4. Robotics
Tesla imagined that, in the future, a race of robots "would be able to perform labor safely and effectively," says io9's Davis. In 1898, he demonstrated a radio-controlled boat he'd invented, which many credit as "being the birth of robotics." He envisioned a world filled with "intelligent cars, robotic human companions, [various] sensors, and autonomous systems."

5. Earthquake machine
"In 1898, Tesla claimed he had built and deployed a small oscillating device that, when attached to his office and operating, nearly shook down the building and everything around it," says Shea Gunther at Revmodo. The device weighed just a few pounds, but Tesla was able to tune the timing of the oscillator at such a frequency that each little vibration added just a little more energy to the wave of flex in the building. "Given enough little pushes, even the largest structure could be shaken apart." Realizing the potential terrors such a device could create, "Tesla said he took a hammer to the oscillator to disable it, instructing his employees to claim ignorance to the cause of the tremors if asked."

Source, Maximum PC, RSNA.org, An Engineer's Aspect, io9, Activist Post, Revmodo

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Increasing processor efficiency by 'shutting off the lights'

To promote energy-efficient multitasking, Harvard graduate student Wonyoung Kim has developed and demonstrated a new device with the potential to reduce the power usage of modern processing chips.

Image courtesy of Wonyoung Kim

The multicore voltage regulator responds almost instantaneously to changes in power demand from each core of the processor. As a result, the power supply matches the demand more closely, conserving energy.

There was a time when a laptop could weigh 10 pounds and still sell, a time when a cell phone was larger than a pocket, and a time when an iPod played only music.
Today’s consumers expect mobile devices that are both smaller and more powerful. All the bells and whistles, however, suck up energy — and a phone that lasts only four hours because it’s also a GPS device is only so useful.
To promote energy-efficient multitasking, Harvard graduate student Wonyoung Kim has developed and demonstrated a new device with the potential to reduce the power usage of modern processing chips.
The advance could allow the creation of “smarter” smartphones, slimmer laptops, and more energy-friendly data centers.
Kim’s on-chip, multicore voltage regulator (MCVR) addresses what amounts to a mismatch between power supply and demand.
“If you’re listening to music on your MP3 player, you don’t need to send power to the image and graphics processors at the same time,” Kim says. “If you’re just looking at photos, you don’t need to power the audio processor or the HD video processor.
“It’s like shutting off the lights when you leave the room.”

 Continue reading here...

Also on Physorg here...

NIST Demonstrates First Quantum 'Entanglement' of Ions Using Microwaves

Laura Ost @ NIST.GOV

Physicists at the National Institute of Standards and Technology (NIST) have, for the first time, linked the quantum properties of two separated ions (electrically charged atoms) by manipulating them with microwaves instead of the usual laser beams. The feat raises the possibility of replacing today's complex, room-sized quantum computing "laser parks" with miniaturized, commercial microwave technology similar to that used in smart phones.

Gold ion trap on aluminum nitride backing. In NIST microwave quantum computing experiments, two ions hover above the middle of the square gold trap, which measures 7.4 millimeters on a side. Scientists manipulate and entangle the ions using microwaves fed into wires on the trap from the three thick electrodes at the lower right. Credit: Y. Colombe/NIST View hi-resolution bottom image

Microwaves have been used in past experiments to manipulate single ions, but the NIST group is the first to position microwaves sources close enough to the ions—just 30 micrometers away—and create the conditions enabling entanglement, a quantum phenomenon expected to be crucial for transporting information and correcting errors in quantum computers.

Described in the August 11, 2011, issue of Nature,* the experiments integrate wiring for microwave sources directly on a chip-sized ion trap and use a desktop-scale table of lasers, mirrors and lenses that is only about one-tenth of the size previously required. Low-power ultraviolet lasers still are needed to cool the ions and observe experimental results but might eventually be made as small as those in portable DVD players. Compared to complex, expensive laser sources, microwave components could be expanded and upgraded more easily to build practical systems of thousands of ions for quantum computing and simulations.

"It's conceivable a modest-sized quantum computer could eventually look like a smart phone combined with a laser pointer-like device, while sophisticated machines might have an overall footprint comparable to a regular desktop PC," says NIST physicist Dietrich Leibfried, a co-author of the new paper.

Quantum computers would harness the unusual rules of quantum physics to solve certain problems—such as breaking today's most widely used data encryption codes—that are currently intractable even with supercomputers. A nearer-term goal is to design quantum simulations of important scientific problems, to explore quantum mysteries such as high-temperature superconductivity, the disappearance of electrical resistance in certain materials when sufficiently chilled.

Ions are a leading candidate for use as quantum bits (qubits) to hold information in a quantum computer. Although other promising candidates for qubits—notably superconducting circuits, or "artificial atoms"—are manipulated on chips with microwaves, ion qubits are at a more advanced stage experimentally in that more ions can be controlled with better accuracy and less loss of information.

The use of microwaves reduces errors introduced by instabilities in laser beam pointing and power as well as laser-induced spontaneous emissions by the ions. However, microwave operations need to be improved to enable practical quantum computations or simulations. The NIST researchers achieved entanglement 76 percent of the time, well above the minimum threshold of 50 percent defining the onset of quantum properties but not yet competitive with the best laser-controlled operations at 99.3 percent.

The research was supported by the Intelligence Advanced Research Projects Activity, Office of Naval Research, Defense Advanced Research Projects Agency, National Security Agency and Sandia National Laboratories.

For more details, see the NIST  news announcement "NIST Physicists 'Entangle' Two Atoms Using Microwaves for the First Time" at www.nist.gov/pml/div688/microwave-quantum-081011.cfm.

 

New combination of nanoparticles and graphene results in a more durable catalytic material for fuel cells

Mary Beckman, PNNL [Source]

Bracing catalyst in material makes fuel cell component work better and last longer

A nanoparticle of indium tin oxide (green and red) braces platinum nanoparticles (blue) on the surface of graphene (black honeycomb) to make a hardier, more chemically active fuel cell material. A new combination of nanoparticles and graphene results in a more durable catalytic material for fuel cells, according to work published today online at the Journal of the American Chemical Society. The catalytic material is not only hardier but more chemically active as well. The researchers are confident the results will help improve fuel cell design.

"Fuel cells are an important area of energy technology, but cost and durability are big challenges," said chemist Jun Liu. "The unique structure of this material provides much needed stability, good electrical conductivity and other desired properties."

Liu and his colleagues at the Department of Energy's Pacific Northwest National Laboratory, Princeton University in Princeton, N.J., and Washington State University in Pullman, Wash., combined graphene, a one-atom-thick honeycomb of carbon with handy electrical and structural properties, with metal oxide nanoparticles to stabilize a fuel cell catalyst and make it better available to do its job.

"This material has great potential to make fuel cells cheaper and last longer," said catalytic chemist Yong Wang, who has a joint appointment with PNNL and WSU. "The work may also provide lessons for improving the performance of other carbon-based catalysts for a broad range of industrial applications."

Muscle Metal Oxide

Fuel cells work by chemically breaking down oxygen and hydrogen gases to create an electrical current, producing water and heat in the process. The centerpiece of the fuel cell is the chemical catalyst — usually a metal such as platinum — sitting on a support that is often made of carbon. A good supporting material spreads the platinum evenly over its surface to maximize the surface area with which it can attack gas molecules. It is also electrically conductive.

Fuel cell developers most commonly use black carbon — think pencil lead — but platinum atoms tend to clump on such carbon. In addition, water can degrade the carbon away. Another support option is metal oxides — think rust — but what metal oxides make up for in stability and catalyst dispersion, they lose in conductivity and ease of synthesis. Other researchers have begun to explore metal oxides in conjunction with carbon materials to get the best of both worlds.

As a carbon support, Liu and his colleagues thought graphene intriguing. The honeycomb lattice of graphene is porous, electrically conductive and affords a lot of room for platinum atoms to work. First, the team crystallized nanoparticles of the metal oxide known as indium tin oxide — or ITO — directly onto specially treated graphene. Then they added platinum nanoparticles to the graphene-ITO and tested the materials.

Platinumweight

The team viewed the materials under high-resolution microscopes at EMSL, DOE's Environmental Molecular Sciences Laboratory on the PNNL campus. The images showed that without ITO, platinum atoms clumped up on the graphene surface. But with ITO, the platinum spread out nicely. Those images also showed catalytic platinum wedged between the nanoparticles and the graphene surface, with the nanoparticles partially sitting on the platinum like a paperweight.

To see how stable this arrangement was, the team performed theoretical calculations of molecular interactions between the graphene, platinum and ITO. This number-crunching on EMSL's Chinook supercomputer showed that the threesome was more stable than the metal oxide alone on graphene or the catalyst alone on graphene.

But stability makes no difference if the catalyst doesn't work. In tests for how well the materials break down oxygen as they would in a fuel cell, the triple-threat packed about 40% more of a wallop than the catalyst alone on graphene or the catalyst alone on other carbon-based supports such as activated carbon.

Last, the team tested how well the new material stands up to repeated usage by artificially aging it. After aging, the tripartite material proved to be three times as durable as the lone catalyst on graphene and twice as durable as on commonly used activated carbon. Corrosion tests revealed that the triple threat was more resistant than the other materials tested as well.

The team is now incorporating the platinum-ITO-graphene material into experimental fuel cells to determine how well it works under real world conditions and how long it lasts.

---

Reference: Rong Kou, Yuyan Shao, Donghai Mei, Zimin Nie, Donghai Wang, Chongmin Wang, Vilayanur V Viswanathan, Sehkyu Park, Ilhan A. Aksay, Yuehe Lin, Yong Wang, Jun Liu, Stabilization of Electrocatalytic Metal Nanoparticles at Metal-Metal Oxide-Graphene Triple Junction Points, February 8, 2011, J. Am. Chem. Soc., DOI 10.1021/ja107719 (http://pubs.acs.org/doi/full/10.1021/ja107719u.

This work was supported by the U.S. Department of Energy Office of Energy Efficiency and Renewable Energy.

High-performance capacitor could lead to better rechargeable batteries

By Lisa Zyga @ physorg.com 

Abstract

Zeolite-templated carbon is a promising candidate as an electrode material for constructing an electric double layer capacitor with both high-power and high-energy densities, due to its three-dimensionally arrayed and mutually connected 1.2-nm nanopores. This carbon exhibits both very high gravimetric (140−190 F g⁻¹) and volumetric (75−83 F cm⁻³) capacitances in an organic electrolyte solution. Moreover, such a high capacitance can be well retained even at a very high current up to 20 A g⁻¹. This extraordinary high performance is attributed to the unique pore structure.

The unique 3D array of nanopores in zeolite-templated carbon enables it to be used as an electrode for high-performance supercapacitors that have a high capacitance and quick charge time. Image credit: Hiroyuki Itoi, et al. ©2011 American Chemical Society.

In order to develop next-generation electric vehicles, solar energy systems, and other clean energy technologies, researchers need an efficient way to store the energy. One of the key energy storage devices for these applications and others is a supercapacitor, also called an electric double-layer capacitor. In a recent study, scientists have investigated the possibility of using a material called zeolite-templated carbon for the electrode in this type of capacitor, and found that the material’s unique pore structure greatly improves the capacitor's overall performance.

To store energy, the electric double-layer capacitor is charged by ions that migrate from a bulk solution to an electrode, where they are adsorbed. Before reaching the electrode’s surface, the ions have to travel through narrow nanopores as quickly and efficiently as possible. Basically, the quicker the ions can travel down these paths, the quicker the capacitor can be charged, resulting in a high rate performance. Also, the greater the adsorbed ion density in the electrode, the greater the charge that the capacitor can store, resulting in a high volumetric capacitance.

Recently, scientists have been testing materials with pores of various sizes and structures to try to achieve both quick ion transport and high adsorption ion density. But the two requirements are somewhat contradictory, since ions can travel more quickly through larger nanopores, but large nanopores make the electrode density low and thus decrease the adsorbed ion density.

The zeolite-templated carbon consists of nanopores that are 1.2 nm in diameter (smaller than most electrode materials) and that have a very ordered structure (whereas other pores can be disordered and random). The nanopores’ small size makes the adsorbed ion density high, while the ordered structure – described as a diamond-like framework – allows the ions to quickly pass through the nanopores. In a previous study, the researchers showed that zeolite-templated carbon with nanopores smaller than 1.2 nm cannot enable fast ion transport, suggesting that this size may provide the optimal balance between high rate performance and high volumetric capacitance.

In tests, the zeolite-templated carbon’s properties exceeded those of other materials, demonstrating its potential to be used as an electrode for high-performance electric double-layer capacitors.

More information: Hiroyuki Itoi, et al. “Three-Dimensionally Arrayed and Mutually Connected 1.2-nm Nanopores for High-Performance Electric Double Layer Capacitor.” Journal of the American Chemical Society. DOI:10.1021/ja108315p

 

Automakers Show Interest in an Unusual Engine Design

The Scuderi engine could substantially improve fuel consumption by storing compressed air.

 

BY KEVIN BULLIS

$50 million engine: It took Scuderi Group most of the $65 million it’s raised so far to develop just one engine, the prototype shown here. It’s a split-cycle two-cylinder engine, in which one cylinder compresses air and the other combusts a fuel-air mixture. 

Credit: Scuderi

Scuderi's Split-Cycle Engine Scuderi Group

An engine development company called the Scuderi Group recently announced progress in its effort to build an engine that can reduce fuel consumption by 25 to 36 percent compared to a conventional design. Such an improvement would be roughly equal to a 50 percent increase in fuel economy.

Sal Scuderi, president of the Scuderi Group, which has raised $65 million since it was founded in 2002, says that nine major automotive companies have signed nondisclosure agreements that allow them access to detailed data about the engine. Scuderi says he is hopeful that at least one of the automakers will sign a licensing deal before the year is over. Historically, major automakers have been reluctant to license engine technology because they prefer to develop the engines themselves as the core technology of their products. But as pressure mounts to meet new fuel-economy regulations, automakers have become more interested in looking at outside technology.

A conventional engine uses a four stroke cycle: air is pulled into the chamber, the air is compressed, fuel is added and a spark ignites the mixture, and finally the combustion gases are forced out of the cylinder. In the Scuderi engine, known as a split-cycle engine, these functions are divided between two adjacent cylinders. One cylinder draws in air and compresses it. The compressed air moves through a tube into a second cylinder, where fuel is added and combustion occurs.

Splitting these functions gives engineers flexibility in how they design and control the engine. In the case of the Scuderi engine, there are two main changes from what happens in a conventional internal-combustion engine. The first is a change to when combustion occurs as the piston moves up and down in the cylinder. The second is the addition of a compressed-air storage tank.

 

Continue reading here.

 

 

 

Irwin Jacobs: Qualcomm founder talks about the future of wireless technologies

JASON PONTIN @ technologyreview.com conducted an interesting Q/A session with Qualcomm founder Irwin Jacobs. Mr. Jacobs offered some inside details on the business side of things and provided guidance for future applications as well.

Qualcomm provided Google with the Snapdragon chip, to launch a phone that didn't require contracts with carriers. The business model didn't work. Why not? What other models might reduce the heavy weight the carriers exert upon innovation?

Google didn't press it very hard because they were then competing with other manufacturers who were making Android phones. And so between not being marketed actively and having more limited distribution and support, that model did not work. But there are certainly situations where you can buy phones retail and then sign up with an operator for the service. We'll see how that develops. There are also other models such as the one that Kindle started, and others have followed, where when you order a book using your Kindle, the information goes out over a cellular network, the book comes back over a cellular network, but you don't pay separately for it—it's just buried in the price of the book. We'll see a number of different business models, driven by competition, driven by the various applications.

What can the wireless industry do to keep up with and manage the unprecedented demands being placed on the network by the growth of mobile video?

The interest of subscribers in video became apparent in South Korea when we first launched some of the 3G services. Video on phones is just going to continue to increase. I don't think users are going to broadcast so much as want video on demand. And that does load the network down quite a bit. That's the reason we developed our MediaFLO technology [a service from Qualcomm that lets mobile carriers stream videos on cell phones]: we wanted a separate frequency band to provide a forward link that carries the videos to the phone. I suspect that additional forward-link-capacity spectrum will be made available and used to support video. The other way one gets spectrum is by having additional base stations. What we'll see is the network evolving to have more and more access points. Some may be in your home. But the spectrum's limited, so we'll have to do things such as reuse the same spectrum.

The mobile market is by no means now limited just to phones. How will Qualcomm change as tablets and other devices become increasingly common?

The key issue with these new devices will be that they'll need chips that use very little energy and provide a lot of computing power. We recognized this early on, and we set up a whole group to research the problem. That's where Snapdragon came from. Those chips were initially only in phones but are now moving up into other devices. This is an important area for Qualcomm, because I believe that tablets will probably become the major computing devices for most people.

Augmented reality has been a significant investment for Qualcomm. Why do you think that augmented reality will be such an important function on our mobile devices?

There are lots of interesting new capabilities. Say I'm in a foreign country: there's a street sign I can't read, so I hold up my phone, and it translates the sign for me. We're beginning to see other examples show up. You might do product comparisons in a shop. You could locate friends who are willing to be located when you approach an area. Since my memory is not as good as it once was, particularly for faces, one I like very much is the possibility of a phone's camera seeing a face and whispering in my ear who that person is.

Continue Reading here.

How Mobile Phones Jump-Start Developing Economies

BY ANTONIO REGALADO @ technologyreview.com

 

Ubiquitous handsets introduce mobile payments to those who lack bank accounts.

 

Virtual wallet: A store in Quito, Ecuador, is one of dozens in the country testing Mony, a way for merchants and suppliers to exchange money by text message. Most Ecuadorians have cell phones but lack bank accounts and must spend time traveling to pay bills in cash. 

Credit: Mony/YellowPepper

 

As one of the fastest-spreading technologies in history, the mobile phone has been transformative for the billions of people in the developing world who never had a landline or an Internet connection. One of the most unexpected benefits is its ability to deliver banking services.

Veronica Suarez, like some 2.5 billion other adults on the planet, has no bank account of her own. Suarez and her husband run a small grocery store in Quito, Ecuador, a city of about 1.4 million people on a plateau ringed with dormant volcanoes. In the past, she would often spend half a day traveling to pay bills in cash. But since June, she has been testing a mobile banking service called Mony, which is run by the Panama-based startup YellowPepper Holding. Now she can simply type out text messages that zap payments to the phones of the delivery men who bring cases of Coca-Cola and boxes of vegetable oil to her shop. That could enable her to save travel time, reduce the risk of getting robbed, and run her business more efficiently.

Continue reading here.

 

 

A Way to Make the Smart Grid Smarter

Kevin Bullis @ technologyreview.com states that new solid-state power-management devices will charge cars fast and make the power grid more flexible and efficient.

Smart Transformer: A prototype of a smart solid-state transformer from the Electric Power Research Institute. It’s smaller and more versatile than today’s transformers. The module on the left converts high-voltage alternating current from the grid to direct current. On the right is an inverter that converts that power to the 120-volt AC that comes out of standard wall outlets. To the right of the outlets are two more power interfaces, one for 240-volt AC power and one for 400-volt DC. 
Credit: EPRI

New semiconductor-based devices for managing power on the grid could make the "smart grid" even smarter. They would allow electric vehicles to be charged fast and let utilities incorporate large amounts of solar and wind power without blackouts or power surges. These devices are being developed by a number of groups, including those that recently received funding from the new Advanced Research Projects Agency for Energy (ARPA-E) and the National Science Foundation.

As utilities start to roll out the smart grid, they are focused on gathering information, such as up-to-the-minute measurements of electricity use from smart meters installed at homes and businesses. But as the smart grid progresses, they'll be adding devices, such as smart solid-state transformers, that will strengthen their control over how power flows through their lines, says Alex Huang, director of a National Research Foundation research center that's developing such devices. "If smart meters are the brains of the smart grid," he says, "devices such as solid-state transformers are the muscle." These devices could help change the grid from a system in which power flows just one way—from the power station to consumers—to one in which homeowners and businesses commonly produce power as well.

Continue reading here.

 

IBM: Graphene as it is won't replace silicon in CPUs

Ben Hardwidge @ bit-tech.net

A single graphene sheet measures just one atom-thick, potentially paving the way tiny transistors.

IBM has revealed that graphene can't yet fully replace silicon inside CPUs, as a graphene transistor can't actually be completely switched off.

In an interview for a forthcoming Custom PC feature about chip-building materials, Yu-Ming Lin from IBM Research - Nanometer Scale Science and Technology told us that 'graphene as it is will not replace the role of silicon in the digital computing regime.'

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via ScribeFire

Shooting for the Sun

Logan Ward | theatlantic.com

From his childhood in segregated Mobile, Alabama, to his run-ins with a nay-saying scientific establishment, the engineer Lonnie Johnson has never paid much heed to those who told him what he could and couldn’t accomplish. Best known for creating the state-of-the-art Super Soaker squirt gun, Johnson believes he now holds the key to affordable solar power.

 

 

Ben Baker/Redux

 

 

In March 2003, the independent inventor Lonnie Johnson faced a roomful of high-level military scientists at the Office of Naval Research in Arlington, Virginia. Johnson had traveled there from his home in Atlanta, seeking research funding for an advanced heat engine he calls the Johnson Thermoelectric Energy Converter, or JTEC (pronounced “jay-tek”). At the time, the JTEC was only a set of mathematical equations and the beginnings of a prototype, but Johnson had made the tantalizing claim that his device would be able to turn solar heat into electricity with twice the efficiency of a photovoltaic cell, and the Office of Naval Research wanted to hear more.

 

Continue reading here.