New World Record Set for Solar Cells: 44% Efficiency

The National Renewable Energy Laboratory (NREL), and their industry partner Solar Junction, have just set the bar even higher in the race for ultra-high-effiency photovoltaic (PV) cells by achieving another world record of 44% efficiency.

The newest cells build on previous successes with multi-junction PV cells (which use layered semiconductors, with each layer optimized to capture different wavelengths of light) and combine them with low-cost concentrating lenses to multiply the intensity of the sun's energy hitting the cells.

Last year, NREL and Solar Junction set a record in efficiency with their SJ3 cells, which are designed for use in utility-scale concentrated solar photovoltaic projects. The SJ3 was verified as being able to convert 43.5% (at 415 suns - a measurement of the intensity of the sun's energy when multiplied) of the energy in sunlight into electricity, but this latest iteration set a new high of 44% efficiency (at 947 suns).

The breakthrough garnered NREL yet another R&D 100 award from R&D Magazine, their third so far, and according to them, it, along with other advances, could "pave the way for a 50%-efficient solar cell in the not-distant future".

Advances such as these are great showcases for the possibilities of public/private partnerships, as Daniel Friedman, manager of the NREL III-V Multijunction Photovoltaics Group states:

"This is really a classic example of NREL developing something and then industry picking it up and running with it and making it a great commercial success. We started with some very basic materials research. We took it to the point where it made sense for industry to take over and take it to the marketplace.

We conceived the cell, demonstrated the individual parts, and let the world know about it. But Solar Junction put all the parts together with record-breaking results, made it work with MBE, and commercialized it at a time when no one else seemed to be interested in or able to do it." - Friedman

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Air Pollution is Responsible for 3 Million Premature Deaths a Year

Flickr/CC BY 2.0

Air quality has certainly improved in the U.S. over the last few decades—thanks to the Clean Air Act—but it's still one of the top health concerns around the world. A new report compiled by global health professionals pegs the toll of outdoor air pollution at a staggering 3.2 million premature deaths a year.

Particulate pollution like soot does the most damage, especially in the booming smog-choked cities across Asia. The report, published in the Lancet, finds that outdoor air pollution is the No. 4 health risk there, right behind smoking. Here in the U.S., it's still a major threat too, despite our progress since the sooty seventies. The report asserts that air pollution is the 8th greatest danger to premature birth worldwide.

The NRDC explains how it is that air pollution is so deadly:

It is the very finest soot – so small that it lodges deep within the lungs and from there enters the bloodstream – that contributes to most of the public health toll of air pollution including mortality. Diesel soot, which is also a carcinogen, is a major problem because it is concentrated in cities along transportation corridors impacting densely populated areas. It is thought to contribute to half the premature deaths from air pollution in urban centers. For example one in six people in the U.S. live near a diesel pollution hot spot like a rail yard, port terminal or freeway.

Point is, there are still hundreds of millions—if not billions—of people around the world who suffer the ill effects of particulate pollution. It's not just premature deaths, either; it's asthma, respiratory illness, cancer, and so on. Transitioning to cleaner energy sources and cleaner, lower-emissions vehicles will begin alleviate that suffering.

And we should be probably be actively working towards a world where three million people don't have to die early every year because they live too near a truck route or a power plant.

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What Have We Got in Common With a Gorilla? Insight Into Human Evolution from Gorilla Genome Sequence

Researchers have just completed the genome sequence for the gorilla -- the last genus of the living great apes to have its genome decoded. While confirming that our closest relative is the chimpanzee, the team show that much of the human genome more closely resembles the gorilla than it does the chimpanzee genome.

This is the first time scientists have been able to compare the genomes of all four living great apes: humans, chimpanzees, gorillas and orang-utans. This study provides a unique perspective on our own origins and is an important resource for research into human evolution and biology, as well as for gorilla biology and conservation.

"The gorilla genome is important because it sheds light on the time when our ancestors diverged from our closest evolutionary cousins. It also lets us explore the similarities and differences between our genes and those of gorilla, the largest living primate," says Aylwyn Scally, first author from the Wellcome Trust Sanger Institute. "Using DNA from Kamilah, a female western lowland gorilla, we assembled a gorilla genome sequence and compared it with the genomes of the other great apes. We also sampled DNA sequences from other gorillas in order to explore genetic differences between gorilla species."

The team searched more than 11,000 genes in human, chimpanzee and gorilla for genetic changes important in evolution. Humans and chimpanzees are genetically closest to each other over most of the genome, but the team found many places where this is not the case. 15% of the human genome is closer to the gorilla genome than it is to chimpanzee, and 15% of the chimpanzee genome is closer to the gorilla than human.

"Our most significant findings reveal not only differences between the species reflecting millions of years of evolutionary divergence, but also similarities in parallel changes over time since their common ancestor," says Dr Chris Tyler-Smith, senior author from the Wellcome Trust Sanger Institute. "We found that gorillas share many parallel genetic changes with humans including the evolution of our hearing. Scientists had suggested that the rapid evolution of human hearing genes was linked to the evolution of language. Our results cast doubt on this, as hearing genes have evolved in gorillas at a similar rate to those in humans."

This research also illuminates the timing of splits between species. Although we commonly think of species diverging at a single point in time, this does not always reflect reality: species can separate over an extended period of time.

The team found that divergence of gorillas from humans and chimpanzees occurred around ten million years ago. The split between eastern and western gorillas was much more recent, in the last million years or so, and was gradual, although they are now genetically distinct. This split is comparable in some ways to the split between chimpanzees and bonobos, or modern humans and Neanderthals.

"Our research completes the genetic picture for overall comparisons of the great apes," says Dr Richard Durbin, senior author from the Wellcome Trust Sanger Institute, "After decades of debate, our genetic interpretations are now consistent with the fossil record and provide a way for palaeontologists and geneticists to work within the same framework.

"Our data are the last genetic piece we can gather for this puzzle: there are no other living great ape genera to study."

Gorillas survive today in just a few isolated and endangered populations in the equatorial forests of central Africa. They are severely threatened and their numbers are diminishing. This research not only informs us about human evolution, but highlights the importance of protecting and conserving the full diversity of these remarkable species.

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HP Labs Using Laser-Powered Chips for Faster, Energy-Efficient Computing

Nothing is faster than the speed of light(except the Neutrinos). So you might think that is why HP Labs wants to use photonics (light) instead of electrons to set new computing speed limits. But you would be wrong.

HP Labs' laser-based chip project, codenamed Corona, would use light instead of electricity to communicate information between chip cores and also from the chips to memory in order to save space and to save energy.

Laser beam

A Short History of Data on the Wire

If you are old enough (or curious enough), you may have tested your soldering skills assembling electronic bits and pieces into primitive number crunchers consisting of transistors that are, literally, wired together. All those electronic parts and wires were replaced by the integrated circuits, aka microchips, which remain the basis of the modern computer.

An integrated circuit consists, typically, of a silicon wafer that carries thousands, or even millions, of electronic components (resistors, capacitors, and transistors) that are "wired" together by electrodeposited metals. The miniaturization and compression of these components are the subject of "Moore's Law", which observes that the number of components in an integrated circuit doubles every 18 months.

There are two major obstacles foreseeable with the continuing growth in computer processing speeds based on the current technology:

1. Miniaturization approaches non-negotiable physical barriers, and
2. Energy consumption increases wildly as data processing rates speed up.

Data transmission by laser addresses both issues.

Rainbows at Nano-scale

Communicating data by light already occurs on a wide-spread basis, via fiber optics. Scaling laser light generation and integrating it onto microchips lies at the heart of the HP Corona project.

MIT has demonstrated the technology to generate laser light using materials that are compatible with microchip manufacturing processes, meaning that tiny lasers could be built directly into integrated circuits. Once generated, the laser light beams along a nano-scale waveguide many times thinner than a single fiber optic cable.

The trick that really saves space copies a technique called Dense Wavelength Division Multiplexing (DWDM), which is currently used in telecommunications: light of different wavelengths can multiply the information sent over a single "light wire". HP Labs has demonstrated that up to 64 wavelengths can be managed in 64 "ring resonators", a circle along the path of waveguide, in less that one millimeter. Using electrical impulses at 10GHz to "tune" the ring resonators results in 10Gb/s of data transmission times 64 wavelengths for 640 Gigabits of data per second running along a single "wire".

Lightening the Energy Demand

Projecting from the energy consumption of current super-computers, an exascale computer (performing 10¹⁸ or a million trillion operations/second) would require its own Hoover Dam worth of power. Most of that power is consumed not in performing operations, but in communicating between parallel processors to schedule tasks and balance loads or in sending data to memory.

Laser-based data transmission reduces heat loads compared to electricity, and the greater bandwidths for communication significantly reduce the power requirements. According to Wired: "Using electronics for a 10-terabytes-per second channel between a CPU and external memory would require 160 watts of power. But HP Labs researchers calculate that using integrated photonics lowers that to 6.4 watts."

Even before exascale computing appears on every desktop, the energy savings could be significant.

Coming Soon to a Desktop Near You

Photonic data transfer between components within an integrated chip needs a decade more research, but data transfer between cores or from cores to memory could come to fruition soon. HP targets bringing a 3-D chip with high-bandwidth photonic communications between 256 processor cores to the market by 2017.

HP's Corona project races against other giants -- such as Intel (Runnemede), MIT (Angstrom), NVIDIA (Echelon), and Sandia National Labs (X-calibur) -- in the search to make high performance computing ubiquitous.

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Apple Advances Toward the iWallet: Is This Good or Bad?

Apple has received a major Granted Patent for a system that will allow it to link users' iTunes accounts to mobile purchases, reported Forbes. To put it extremely simply, this is Apple's war on cold hard cash: the iWallet. But what does the potential end of paper and metal currency mean for the planet, and just how much better or worse off would be off using iPhones and iPads instead?

The Upsides

A dollar bill has 3 grams of embodied greenhouse gases in it. (A dollar coin has 15 grams, but lasts longer and is recyclable, among other advantages.)

Taking the physical money out of the equation makes that carbon footprint go away. If Apple (and Google, which has a similar experiment going) can head off security questions, it could make carrying around cash at night a whole lot safer. Of course, you can still get mugged for your iPhone.

Also, shopping with your smartphone can make you a more sustainably-minded and informed consumer.

The Downsides

It's not all good. First of all, this is more of what Apple does best: promote and enable consumerism, which provokes existential questions about the green movement, not to mention our economy and society. But that's another discussion.

Assuming that we would buy as much with cash as with an iWallet, e-money comes with its own carbon footprint. However many good green things you can do with them, smartphones and tablets take an enormous toll on the planet through their production. Not to mention the ethical firestorm Apple just rode out over its factories in China.

So?

Apple and Google aren't the only ones attempting to "cash in" on this wave of the future: Square and Intuit already process payments via smartphone. If they all fail, more attempts will likely be made anyway. Like books, money is moving more and more out of our hands and onto our screens.

Ultimately, tacking consumerism, and not its 21st century incarnation, must be the way to go. Kill the snake by cutting off its head.

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United Arab Emirates Speeds Up Ban On Disposable Plastics

The United Arab Emirates has moved forward a ban on all disposable plastic products, except those made from oxo-biodegradable plastics, from 2013 to the end of this year.

Though oxo-biodegradable plastics cannot be composted as some biodegradable plastics can, if left in the open they will decompose within 2-18 months. In a landfill decomposition occurs much more slowly however, though still far more quickly than ordinary plastics.

The ban, enacted by the Ministry of Environment and Water, was precipitated over concerns about plastic waste in the desert and the sea, and the effect of that on wildlife.

Covered in the ban are all packaging and disposable plastic products such as shopping bags, packaging for food, magazines, garbage bags, shrink and pallet wrap, cling film, as well as other plastic designed to be used over short periods and discarded. (Packaging Gateway)

The regulation also includes a standard for registration of companies manufacturing and importing biodegradable plastics. The Intelligent SMEquotes Eng. Mohammed Saleh Al Badri of the Emirates Authority for Standardization and Metrology:

ESMA officials will visit each factory and see that the manufacturing process complies with our specification. So, basically, the raw materials, additives, and manufacturing process, will be pre-approved by us. The companies will have regular monitoring, and we will collect finished samples, as well as the ones still being made for testing. Unannounced visits will be made to ensure consistency. At this point, we don’t have a testing centre, so all samples are sent abroad, but we are encouraging labs to take up this facility within the country. This regulatory measure will ensure that all the plastic bags used in the country will be degradable to harmless substances that will not affect the environment.

East Africa Pushes For Plastic Ban
All of this comes as the East African Community legislative assembly—an intergovernmental organization for Burundi, Kenya, Rwanda, Tanzania, and Uganda—has passed 'The East African Community Plastics Control Bill'.

If all heads of state of the member countries sign it, the bill would provide the legal framework for the outright banning of the manufacturing, sale, import and use of polyethylene material.

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ALL DESIGN TEWind Chime Charges Up With The Breeze For Outdoor Lighting

What if the pleasantness of a wind chime did double duty as an energy generator that powered an LED light? A team of designers including Chen Yan Zhuang, Zhou Li, Peng Qixuan, Liu Huan-jung, Ke Qi Ling and Zhong Zhida came up with the idea that shifts a wind chime into a energy-gathering device for evening lighting. Yanko Design writes, "The only difference is that the wind movement causes the lamp to harness energy to power the lamp rather than sound the soothing 'clinks'."

I think I'd like it better if it included the clinks. This is vaporware to the nth degree, but if we're in design la-la-land, I'd like to put in a request that the pleasant clinks still be included. Not only does the wind chime generate electricity for the LED light, but the wind-catching board is also a touch board for the user to write down "hopes." If we can do that then we can certainly keep it clinky.

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