Great things from small things

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Tesla Home 050815 _1x519_0  Tesla launches a stationary battery aimed at companies with variable electricity rates and homes with solar panels.

Seeking to expand its business beyond electric vehicles, Tesla Motors will sell stationary batteries for residential, commercial, and utility use under a new brand, Tesla Energy.

Tesla is launching the home battery business partly because it’s already making vehicle batteries—and as a result it can benefit from the economies of scale that come from making both. Another reason is that the market for storage is expected to grow in concert with the use of solar power. Tesla needs both electric vehicles and solar power to boom if it hopes to fulfill the projected output from a vast $5 billion battery “gigafactory” it’s building in Nevada.

“The obvious problem with solar power is that the sun does not shine at night,” Tesla CEO Elon Musk said at the unveiling of the new batteries at the company’s design studio in Hawthorne, California, yesterday. “We need to store the energy that is generated during the day so you can use it at night.”

A number of solar companies now offer batteries to accompany their solar panels (see “Solar Power, and Somewhere to Store It”). Although just a tenth of a percent of U.S. homes now get power from rooftop solar panels combined with energy storage, such systems could account for 3 percent of homes by 2018, according to Greentech Media Research.

Tesla’s residential battery, called Powerwall, will be available in several months and will come in two sizes, a seven-kilowatt-hour battery system that costs $3,000 and a slightly larger 10-kilowatt-hour system for $3,500. The larger battery would keep an average-sized home running for a day. It is unclear what the cost of installation would be.

Tesla expects that many sales will come from commercial customers who pay a variable rate of electricity over the course of a day based on demand. Such customers already see significant reductions in their energy bills by drawing on stored electricity during periods of peak energy demand.

In the near term, the market for home energy storage will depend on how states regulate homeowners’ ability to buy and sell electricity. Net metering, currently available in 43 states, allows residential customers to sell excess generation back to their utility company at retail rates. The policies are being challenged by utility companies that say it undermines their ability to recoup grid infrastructure costs. But as long as net metering continues, consumers will have little need to buy an energy storage system because they can sell the excess solar power they generate rather than store it, says Jay Stein, an analyst with energy consulting company E Source. “I don’t see any financial payoff for them to buy batteries,” he says.

Most utilities that offer net metering, however, also allow residential customers to buy and sell electricity at rates that vary throughout the day based on demand. Battery storage would allow such people to maximize the value of the electricity they sell back to the utility.

“There are some arbitrage values emerging,” says Karl Rábago, executive director of the Pace Energy and Climate Center in White Plains, New York. “If I could export selectively, using a storage device, I might beget higher value for my generation.”

Home energy storage will make more sense in the years to come. Residential and commercial solar-plus-storage systems will offer a clear cost advantage over electricity from the grid throughout the United States by 2030, according to a recent report by the Rocky Mountain Institute, an energy research and consulting group.

Tesla’s Nevada gigafactory, which it’s building with Panasonic, will have an annual production capacity of 35 gigawatt-hours by 2020, more than all the lithium-ion batteries produced globally in 2013.tesla-motors-gigafactory-statistics-from-feb-2014-presentation_100457895_l

Such a large investment in what is still a niche market is risky, but Tesla claims that the new factory will cut battery costs by 30 percent when it begins operations, as early as 2016. Tesla’s biggest challenge will likely be filling enough orders for the output. By 2020, the plant will be able to produce enough batteries for half a million electric vehicles per year. Last year, Tesla sold around 20,000 cars.


California Water 0426 AAbtvCj      The Plan To Fix Our Aging Water Distribution System

The Problem

California homes, farms and businesses depend on water that flows from the Sierra Nevada Mountains through the state’s main water distribution system to regions across the state, including the Bay Area, Central Valley, Central Coast and Southern California. But key portions of the system are outdated and crumbling, putting the security and reliability of our local water supplies at risk. Experts warn that the system could collapse in an earthquake, and is susceptible to salt water intrusion during major droughts or natural disasters.

The Solution

The plan to fix California’s water system, known as the California Water Fix, will address the severe vulnerability in our water infrastructure and secure local water supplies. Outdated, dirt levees would be replaced with a modern water pipeline built to withstand Earthquakes and other natural disasters. Natural water flows would be restored to support the surrounding environs. The plan is critical for many California communities and our state’s economy. Learn more by scrolling down, and join our broad coalition.

Read About the Plan Here:

Californians for Water Security


Canada Disrupt Tech extPreparing for Canada’s disruption storm | Deloitte Canada advances in technology are about to disrupt Canada’s business landscape. Robots, 3D printing, artificial intelligence, crowds, clouds and the Internet of Things will profoundly change our … (“Oh Canada ~ Eh!?”)

Read About Here:

Preparing for Canada’s Disruptive Storm

Silicon Photonics id39403 Researchers at the University of Rochester have shown that defects on an atomically thin semiconductor can produce light-emitting quantum dots. The quantum dots serve as a source of single photons and could be useful for the integration of quantum photonics with solid-state electronics — a combination known as integrated photonics.

Scientists have become interested in integrated solid-state devices for quantum information processing uses. Quantum dots in atomically thin semiconductors could not only provide a framework to explore the fundamental physics of how they interact, but also enable nanophotonics applications, the researchers say.

Quantum dots are often referred to as artificial atoms. They are artificially engineered or naturally occurring defects in solids that are being studied for a wide range of applications. Nick Vamivakas, assistant professor of optics at the University of Rochester and senior author on the paper, adds that atomically thin, 2D materials, such as graphene, have also generated interest among scientists who want to explore their potential for optoelectronics. However, until now, optically active quantum dots have not been observed in 2D materials.

In a paper published in Nature Nanotechnology this week, the Rochester researchers show how tungsten diselenide (WSe2) can be fashioned into an atomically thin semiconductor that serves as a platform for solid-state quantum dots. Perhaps most importantly the defects that create the dots do not inhibit the electrical or optical performance of the semiconductor and they can be controlled by applying electric and magnetic fields.

Vamivakas explains that the brightness of the quantum dot emission can be controlled by applying the voltage. He adds that the next step is to use voltage to “tune the color” of the emitted photons, which can make it possible to integrate these quantum dots with nanophotonic devices.

A key advantage is how much easier it is to create quantum dots in atomically thin tungsten diselenide compared to producing quantum dots in more traditional materials like indium arsenide.

“We start with a black crystal and then we peel layers of it off until we have an extremely thin later left, an atomically thin sheet of tungsten diselenide,” said Vamivakas.1-nano devices howtomakemob

The researchers take two of these atomically thin sheets and lay one over the other one. At the point where they overlap, a quantum dot is created. The overlap creates a defect in the otherwise smooth 2D sheet of semiconductor material. The extremely thin semiconductors are much easier to integrate with other electronics.

The quantum dots in tungsten diselenide also possess an intrinsic quantum degree of freedom — the electron spin. This is a desirable property as the spin can both act as a store of quantum information as well as provide a probe of the local quantum dot environment.

COMING ~ JUNE 2015 ~ WATCH OUR NEW VIDEO ~ Genesis Nanotechnology ~ “Great Things from Small Things”

“What makes tungsten diselenide extremely versatile is that the color of the single photons emitted by the quantum dots is correlated with the quantum dot spin,” said first author Chitraleema Chakraborty. Chakraborty added that the ease with which the spins and photons interact with one another should make these systems ideal for quantum information applications as well as nanoscale metrology.

Story Source:

The above story is based on materials provided by University of Rochester. Note: Materials may be edited for content and length.

Difference engine

Graphene’s lightbulb moment

Can the “wonder material” live up to all the hype?

PHYSICISTS Andre Geim and Kostya Novoselev have been rightly feted for their isolation, in 2003, of graphene—sheets of pure carbon a single atom thick—whose existence had been pondered for decades, but which theory suggested was too unstable to survive. The two Soviet-born researchers won the Nobel physics prize in 2010 for their groundbreaking work, carried out at Manchester University, which involved peeling layers of graphene from blocks of graphite. Both men, now British citizens, were knighted in 2012 for their contribution to science. Their work has won generous support from the British government and the European Union—in particular, the construction, at a cost of £61m ($92m), of the National Graphene Institute, which was opened by George Osborne, Chancellor of the Exchequer, in March.

The researchers now have another distinction to their credit: their discovery is about to become a commercial product. A graphene-based lightbulb, said to be longer-lasting, more efficient and cheaper to make than today’s domestic LED lamps, will go on sale in a few months’ time. Though graphene flakes have already been incorporated into tennis racquets, skis and conductive ink, the new lightbulb is claimed by its manufacturer—Graphene Lighting Plc, a spin-out from the National Graphene Institute and Manchester University—to be the first commercially viable consumer product based on the material.

That may be splitting hairs. Even so, going from discovery to commercialisation in little more than a decade is quick. Many entrepreneurial companies find turning an invention into a successful innovation can take 20 years or more.

Graphene is composed of a single layer of carbon atoms arranged in the form of a hexagonal lattice. This means there is a world of difference between it and a three-dimensional crystalline structure like graphite. The electrons associated with carbon atoms in graphite can interact with other carbon atoms in the layers above and below them. In a sheet, this electron-coupling effect disappears, and the electrons are free to behave in entirely different ways.

The most striking consequence of this is that those electrons are thus able to move great distances at close to the speed of light, resulting in a material that has exceptionally low resistance. Because graphene can transport electricity 200 times faster than silicon, it seems a good candidate to replace that element as the semiconductor material used in computer chips.

Hype aside, graphene has not been called a “wonder material” for nothing. Apart from its remarkable electrical properties (and also, thermal and acoustical properties), it is the thinnest and lightest substance known, as well as being the strongest (more than 100 times stronger than high-strength steel). As if all that were not enough, graphene is also extremely flexible and almost totally transparent, absorbing only a minuscule amount of the light falling on it.

As such, potential applications of graphene appear myriad. Some of the more obvious ones include rapid-charging lithium-ion batteries, better solar cells, compact supercapacitors, printable electronics, foldable LED touchscreens, tunable sensors, ultrafast molecular sieves, improved DNA sequencers, corrosion-resistant coatings, a replacement for Kevlar, terahertz wave generators for extremely fast wireless communication, and, of course, more efficient lightbulbs. The list of proposals for future graphene products goes on and on, as researchers cozy up to potential sponsors.

There is little, save lack of money and consumer interest, to stop a good number of these suggestions reaching the market in the not-too-distant future. But the one graphene application that could turn the whole of electronics on its head—a replacement for silicon-based semiconductors—remains tantalisingly over the horizon.

Big computer, wireless and electronics firms—including such research powerhouses as IBM, Intel and Samsung—have been racing to create a field-effect transistor that uses graphene instead of silicon. They have a big incentive to do so. After 50 years of success, Moore’s Law (that the processing power of semiconductor devices doubles every 18 months or so) appears to be coming to an end, at least as far as silicon is concerned. Another material is needed to take its place.

Despite the billions poured into finding an alternative, attempts to make graphene work as a semiconductor have been disappointing. The problem is that the material has no “band gap”—the property that makes a solid an insulator (large band gap), a conductor (tiny or no band gap) or something in between—ie, a semiconductor (small band gap). Having no band gap at all is why graphene is such an excellent conductor. Making it into a semiconductor is tricky.

That is not all. A transistor works by flipping between two states—one insulating and the other conductive—in the presence of an electric field. These two states (off and on) represent the digital zeros and ones of computerspeak. By its nature, a graphene gate (switch) is on all the time. Getting it to turn off, let alone flip on and off billions of times a second, is the stumbling block.

There have been various attempts to open a band gap in graphene. One approach has been to dope it with compounds like silicon carbide or boron nitride that have matching crystalline lattice structures. Unfortunately, creating a band gap big enough to turn graphene into a usable semiconductor destroys the very properties—especially the high electron mobility—that made the material so attractive in the first place.

Older and wiser, researchers have turned to building hybrid chips that are fabricated, layer by layer, using conventional silicon epitaxy for everything except the final graphene transistor channels on the top of the device. These delicate structures are added at the end, so as not to get damaged during fabrication. So far, only analogue chips have been built this way. Even IBM has failed to create a band gap in graphene that would result in a digital device capable of challenging silicon’s preeminence. Transistors made entirely from graphene appear to be decades away.

So, where does that leave graphene’s prospects? While a replacement for silicon may be a long shot, many applications that do not rely on a band gap have a better chance of success. That said, not all graphene proposals being hyped at present can expect to survive the inevitable shake-out.

Had Gartner, an information-technology consultancy in Connecticut, included graphene-based processes as a stand-alone entry in its latest Emerging Technologies Hype Cycle, such processes would be over two-thirds the way up the slope to its “peak of inflated expectations”,which comes before the tip-over into the “trough of disillusionment” (see “Divining reality from hype”, August 27th 2014). Experience suggests that only those innovations which show genuine commercial value manage to crawl out of the trough and up the subsequent slope of enlightenment towards the plateau of productivity and market acceptance. Venture capitalists reckon no more than one in seven, at this stage of development, manages such a feat. It is too early to say whether graphene lightbulbs will be among them.

Readers with long memories may have noticed how the trajectory graphene is following resembles the one blazed by carbon fibre back in the 1960s. Then, as now, the new material was seen as a wonder product that would have numerous applications. Then, as now also, the British government felt it had a sacred duty to protect and promote what it perceived to be a home-grown invention—with the promise of jobs and exports.

If truth be told, the first hank of pyrolysed nylon (a carbon-fibre precursor) was snaffled from a Japanese textile factory and flown back to Britain in a diplomatic bag. At the time, British officials involved considered the super-strength material ideal for making gas centrifuges for enriching uranium. But samples that landed up at the Royal Aircraft Establishment in Farnborough led to the first carbon-fibre composite (Hyfil) being made available to select industrial partners, including the aeroengine manufacturer Rolls-Royce.

Of the many applications touted for carbon fibre, its promise to revolutionise air travel captured the most attention. With stronger, lighter fan blades, made from Hyfil instead of aluminium alloy or titanium, in a fan-jet’s first compressor stage, Rolls-Royce’s latest aircraft engine at the time, the RB211, would have had a significant weight-saving advantage—and thus better fuel economy—over rivals from General Electric and Pratt & Whitney.

The outcome was rather different. While turbine blades made from Hyfil had all the tensile strength, and more, to withstand the centrifugal forces of a big fan engine at full power, their shear strength left much to be desired. The story of how compressor blades shattered when a frozen chicken was fired at them to simulate bird impact contributed to carbon fibre’s fall from grace.

Meanwhile, the cost and delay involved in replacing the RB211’s Hyfil blades with titanium ones plunged Rolls-Royce into bankruptcy. Britain’s proudest engineering firm then had to be rescued at taxpayer expense. So much for governments picking winners. Hopefully, graphene is spared a similar fate.

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