Declining Energy Quality Could Be Root Cause of Current Recession, Expert Suggests

Many economists have pointed to a bursting real estate bubble as the initial trigger for the current recession, which in turn caused global investments in U.S. real estate to turn sour and drag down the global economy. King suggests the real estate bubble burst because individuals were forced to pay a higher and higher percentage of their income for energy -- including electricity, gasoline and heating oil -- leaving less money for their home mortgages.

In economic terms, the quality of the nation's energy supply is referred to as Energy Return on Energy Investment (EROI). For example, if an oil company uses a 10th of a barrel of oil to drill, pump, transport and refine one barrel of oil, the EROI for the refined fuel is 10.

"Many economists don't think of energy as being a limiting factor to economic growth," says King, a research associate in the university's Center for International Energy and Environmental Policy."They think continual improvements in technology and efficiency have completely decoupled the two factors. My research is part of a growing body of evidence that says that's just not true. Energy still plays a big role."

In a paper published this November in the journalEnvironmental Research Letters, King introduced a new way to measure energy quality, the Energy Intensity Ratio (EIR), that is easier to calculate, highly correlated to EROI and in some ways more powerful than EROI. EIR measures how much profit is obtained by energy consumers relative to energy producers. The higher the EIR, the more economic value consumers (including businesses, governments and people) get from their energy.

When King plots EIR for various fuels every year since World War II, the graphs indicate two large declines, one before the recessions of the mid-1970s and early 1980s and the other during the 2000s, leading up to the current economic recession. There have been other recessions in the U.S. since World War II, but the longest and deepest were preceded by sustained declines in EIR for all fossil fuels.

EIR is proportional to EROI, meaning they rise and fall together, but the basic data behind the EIR calculations come out annually as opposed to every five years for EROI. EIR also gives insight into different parts of the supply chain such as at the refinery or at the gas pump, which are harder to study with EROI.

King's analysis suggests if EIR falls below a certain threshold, the economy stops growing. For example, in 1972, EIR for gasoline was 5.9 and in 2008 it was 5.5. During times of robust economic growth, such as the 1990s, EIR for gasoline was well over eight. Compare that to some estimates of EROI and EIR for corn ethanol of around one, and it's clear why corn ethanol has been widely criticized as a low quality energy source.

To get the U.S. economy growing again, King says Americans will have to produce and use energy more efficiently. That's essentially what the U.S. did after the last energy crisis by raising fuel efficiency standards for cars, increasing use of natural gas for electric power generation and developing new technologies such as Enhanced Oil Recovery to coax more oil out of the ground.

"If we aren't fundamentally changing the way we produce or consume energy now, don't expect the economy to grow as much as the past two decades," he says.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.

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Imaging With Neutrons: Magnetic Domains Shown for the First Time in 3-D

Up until now, it has only been possible to image magnetic domains in 2 dimensions. Now, for the first time, scientists at Helmholtz-Zentrum Berlin have managed to create 3-dimensional images of these domains deep within magnetic materials.

Every magnetic material is divided into such magnetic domains. Scientists call them"Weiss domains" after physicist Pierre-Ernest Weiss, who predicted their existence theoretically more than a hundred years ago. In 1907, he recognized that the magnetic moments of atoms within a bounded domain are equally aligned.

All pursuit of this theory has so far been limited to two-dimensional images and material surfaces. Accordingly, researchers have only ever been able to see a domain in cross section. Together with colleagues from the German Federal Institute for Materials Research and Testing and the Swiss Paul-Scherrer-Institute, Dr. Ingo Manke and his group at the Institute of Applied Material Research at HZB have developed a method by which they can image the full spatial structure of magnetic domains -- even deep within materials. To do this, special iron-silicon crystals were produced at the Leibniz Institute for Solid State and Materials Research Dresden, for which the research group of Rudolf Schäfer had already developed model representations. Their actual existence has now been proven for the first time. With it, the researchers have solved a decade-old problem in imaging. 

Most magnetic materials consist of a complex network of magnetic domains. The researchers' newly developed method exploits the areas where the domains meet -- the so-called domain walls. Within a domain, all magnetic moments are the same, but the magnetic alignment is different from one domain to another. So, at each domain wall, the direction of the magnetic field changes. The researchers exploit these changes for their radiographic method in which they use not light, but neutrons.

Magnetic fields deflect the neutrons slightly from their flight path, just as water diverts light. An object under water cannot be directly perceived because of this phenomenon; the object appears distorted and in a different location. Similarly, the neutrons pass through domain walls along their path through the magnetic material. At these walls, they are diverted into different directions.

This diversion, however, is only a very weak effect. It is typically invisible in a neutron radiogram, since it is overshadowed by non-diverted rays. The researchers therefore employ several diffraction gratings in order to separate the diverted rays. During a measurement, they rotate the sample and shoot rays through it from all directions. From the separated rays, they can calculate all domain shapes and generate an image of the domain network in its entirety.

Magnetic domains are important for understanding material properties and the natural laws of physics. They also play an important role in everyday life: most notably in storage media such as hard disks, for example, or battery chargers for laptops or electric vehicles. If the domain properties are carefully chosen to minimize electricity loss at the domain walls, the storage medium becomes more efficient.

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Enhancing the Efficiency of Wind Turbines

New ideas for enhancing the efficiency of wind turbines are being presented this week at the American Physical Society Division of Fluid Dynamics meeting in Long Beach, CA.

One issue confronting the efficiency of wind energy is the wind itself -- specifically, its changeability. The aerodynamic performance of a wind turbine is best under steady wind flow, and the efficiency of the blades degrades when exposed to conditions such as wind gusts, turbulent flow, upstream turbine wakes, and wind shear.

Now a new type of air-flow technology may soon increase the efficiency of large wind turbines under many different wind conditions.

Syracuse University researchers Guannan Wang, Basman El Hadidi, Jakub Walczak, Mark Glauser and Hiroshi Higuchi are testing new intelligent-systems-based active flow control methods with support from the U.S. Department of Energy through the University of Minnesota Wind Energy Consortium. The approach estimates the flow conditions over the blade surfaces from surface measurements and then feeds this information to an intelligent controller to implement real-time actuation on the blades to control the airflow and increase the overall efficiency of the wind turbine system. The work may also reduce excessive noise and vibration due to flow separation.

Initial simulation results suggest that flow control applied on the outboard side of the blade beyond the half radius could significantly enlarge the overall operational range of the wind turbine with the same rated power output or considerably increase the rated output power for the same level of operational range. The team is also investigating a characteristic airfoil in a new anechoic wind tunnel facility at Syracuse University to determine the airfoil lift and drag characteristics with appropriate flow control while exposed to large-scale flow unsteadiness. In addition, the effects of flow control on the noise spectrum of the wind turbine will be also assessed and measured in the anechoic chamber.

Another problem with wind energy is drag, the resistance felt by the turbine blades as they beat the air. Scientists at the University of Minnesota have been looking at the drag-reduction effect of placing tiny grooves on turbine blades. The grooves are in the form of triangular riblets scored into a coating on the blade surface. They are so shallow (between 40 and 225 microns) that they can't be seen by the human eye -- leaving the blades looking perfectly smooth.

Using wind-tunnel tests of 2.5 megawatt turbine airfoil surfaces (becoming one of the popular industry standards) and computer simulations, they are looking at the efficacies of various groove geometries and angles of attack (how the blades are positioned relative to the air stream).

Riblets like these have been used before, in the sails on sailboats taking part in the last America's Cup regatta and on the Airbus airliner, where they produced a drag reduction of about 6 percent. The design of wind turbine blades was, at first, closely analogous to that of airplane wings. But owing to different engineering concerns, such as turbine blades having a much thicker cross section close to the hub and wind turbines having to cope with peculiar turbulence near the ground, drag reduction won't be quite the same for wind turbines.

University of Minnesota researchers Roger Arndt, Leonardo P. Chamorro and Fotis Sotiropoulos believe that riblets will increase wind turbine efficiency by about 3 percent.

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Electrowetting Breakthrough May Lead to Disposable E-Readers Fast Enough for Video

In the research, Steckl and UC doctoral student Duk Young Kim demonstrated that paper could be used as a flexible host material for an electrowetting device. Electrowetting (EW) involves applying an electric field to colored droplets within a display in order to reveal content such as type, photographs and video. Steckl's discovery that paper could be used as the host material has far-reaching implications considering other popular e-readers on the market such as the Kindle and iPad rely on complex circuitry printed over a rigid glass substrate.

"One of the main goals of e-paper is to replicate the look and feel of actual ink on paper," the researchers stated in the ACS article."We have, therefore, investigated the use of paper as the perfect substrate for EW devices to accomplish e-paper on paper."

Importantly, they found that the performance of the electrowetting device on paper is equivalent to that of glass, which is the gold standard in the field.

"It is pretty exciting," said Steckl."With the right paper, the right process and the right device fabrication technique, you can get results that are as good as you would get on glass, and our results are good enough for a video-style e-reader."

Steckl imagines a future device that is rollable, feels like paper yet delivers books, news and even high-resolution color video in bright-light conditions.

"Nothing looks better than paper for reading," said Steckl, an Ohio Eminent Scholar."We hope to have something that would actually look like paper but behave like a computer monitor in terms of its ability to store information. We would have something that is very cheap, very fast, full-color and at the end of the day or the end of the week, you could pitch it into the trash."

Disposing of a paper-based e-reader, Steckl points out, is also far simpler in terms of the environmental impact.

"In general, this is an elegant method for reducing device complexity and cost, resulting in one-time-use devices that can be totally disposed after use," the researchers pointed out.

Steckl's goal is attract commercial interest in the technology for next-stage development, which he expects will take three to five years to get to market.

The work was supported, in part, by a grant from the National Science Foundation and was conducted at the Nanoelectronics Laboratory at the University of Cincinnati College of Engineering and Applied Science.

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Short, on-Chip Light Pulses Will Enable Ultrafast Data Transfer Within Computers

Details appeared online in the journalNature Communicationson November 16.

This miniaturized short pulse generator eliminates a roadblock on the way to optical interconnects for use in PCs, data centers, imaging applications and beyond. These optical interconnects, which will aggregate slower data channels with pulse compression, will have far higher data rates and generate less heat than the copper wires they will replace. Such aggregation devices will be critical for future optical connections within and between high speed digital electronic processors in future digital information systems.

"Our pulse compressor is implemented on a chip, so we can easily integrate it with computer processors," said Dawn Tan, the Ph.D. candidate in the Department of Electrical and Computer Engineering at UC San Diego Jacobs School of Engineering who led development of the pulse compressor.

"Next generation computer networks and computer architectures will likely replace copper interconnects with their optical counterparts, and these have to be complementary metal oxide semiconductor (CMOS) compatible. This is why we created our pulse compressor on silicon," said Tan, an electrical engineering graduate student researcher at UC San Diego, and part of the National Science Foundation funded Center for Integrated Access Networks.

The pulse compressor will also provide a cost effective method to derive short pulses for a variety of imaging technologies such as time resolved spectroscopy -- which can be used to study lasers and electron behavior, and optical coherence tomography -- which can capture biological tissues in three dimensions.

In addition to increasing data transfer rates, switching from copper wires to optical interconnects will reduce power consumption caused by heat dissipation, switching and transmission of electrical signals.

"At UC San Diego, we recognized the enabling power of nanophotonics for integration of information systems close to 20 years ago when we first started to use nano-scale lithographic tools to create new optical functionalities of materials and devices -- and most importantly, to enable their integration with electronics on a chip. This Nature Communications paper demonstrates such integration of a few optical signal processing device functionalities on a CMOS compatible silicon-on-insulator material platform," said Yeshaiahu Fainman, a professor in the Department of Electrical and Computer Engineering in the UC San Diego Jacobs School of Engineering. Fainman acknowledged DARPA support in developing silicon photonics technologies which helped to enable this work, through programs such as Silicon-based Photonic Analog Signal Processing Engines with Reconfigurability (Si-PhASER) and Ultraperformance Nanophotonic Intrachip Communications (UNIC).

Pulse Compression for On-Chip Optical Interconnects

The compressed pulses are seven times shorter than the original -- the largest compression demonstrated to date on a chip.

Until now, pulse compression featuring such high compression factors was only possible using bulk optics or fiber-based systems, both of which are bulky and not practical for optical interconnects for computers and other electronics.

The combination of high compression and miniaturization are possible due to a nanoscale, light-guiding tool called an"integrated dispersive element" developed and designed primarily by electrical engineering Ph.D. candidate Dawn Tan.

The new dispersive element offers a much needed component to the on-chip nanophotonics tool kit.

The pulse compressor works in two steps. In step one, the spectrum of incoming laser light is broadened. For example, if green laser light were the input, the output would be red, green and blue laser light. In step two, the new integrated dispersive element developed by the electrical engineers manipulates the light so each spectrum in the pulse is travelling at the same speed. This speed synchronization is where pulse compression occurs.

Imagine the laser light as a series of cars. Looking down from above, the cars are initially in a long caravan. This is analogous to a long pulse of laser light. After stage one of pulse compression, the cars are no longer in a single line and they are moving at different speeds. Next, the cars move through the new dispersive grating where some cars are sped up and others are slowed down until each car is moving at the same speed. Viewed from above, the cars are all lined up and pass the finish line at the same moment.

This example illustrates how the on-chip pulse compressor transforms a long pulse of light into a spectrally broader and temporally shorter pulse of light. This temporally compressed pulse will enable multiplexing of data to achieve much higher data speeds.

"In communications, there is this technique called optical time division multiplexing or OTDM, where different signals are interleaved in time to produce a single data stream with higher data rates, on the order of terabytes per second. We've created a compression component that is essential for OTDM," said Tan.

The UC San Diego electrical engineers say they are the first to report a pulse compressor on a CMOS-compatible integrated platform that is strong enough for OTDM.

"In the future, this work will enable integrating multiple 'slow' bandwidth channels with pulse compression into a single ultra-high-bandwidth OTDM channel on a chip. Such aggregation devices will be critical for future inter- and intra-high speed digital electronic processors interconnections for numerous applications such as data centers, field-programmable gate arrays, high performance computing and more," said Fainman, holder of the Cymer Inc. Endowed Chair in Advanced Optical Technologies at the UC San Diego Jacobs School of Engineering and Deputy Director of the NSF-funded Center for Integrated Access Networks.

This work was supported by the Defense Advanced Research Projects Agency, the National Science Foundation (NSF) through Electrical, Communications and Cyber Systems (ECCS) grants, the NSF Center for Integrated Access Networks ERC, the Cymer Corporation and the U.S. Army Research Office.

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Methane-Powered Laptops? Materials Scientists Unveil Tiny, Low-Temperature Methane Fuel Cells

With advances in nanostructured devices, lower operating temperatures, and the use of an abundant fuel source and cheaper materials, a group of researchers led by Shriram Ramanathan at the Harvard School of Engineering and Applied Sciences (SEAS) are increasingly optimistic about the commercial viability of the technology.

Ramanathan, an expert and innovator in the development of solid-oxide fuel cells (SOFCs), says they may, in fact, soon become the go-to technology for those on the go.

Electrochemical fuel cells have long been viewed as a potential eco-friendly alternative to fossil fuels -- especially as most SOFCs leave behind little more than water as waste.

The obstacles to using SOFCs to charge laptops and phones or drive the next generation of cars and trucks have remained reliability, temperature, and cost.

Fuel cells operate by converting chemical energy (from hydrogen or a hydrocarbon fuel such as methane) into an electric current. Oxygen ions travel from the cathode through the electrolyte toward the anode, where they oxidize the fuel to produce a current of electrons back toward the cathode.

That may seem simple enough in principle, but until now, SOFCs have been more suited for the laboratory rather than the office or garage. In two studies appearing in theJournal of Power Sourcesthis month, Ramanathan's team reported several critical advances in SOFC technology that may quicken their pace to market.

In the first paper, Ramanathan's group demonstrated stable and functional all-ceramic thin-film SOFCs that do not contain any platinum.

In thin-film SOFCs, the electrolyte is reduced to a hundredth or even a thousandth of its usual scale, using densely packed layers of special ceramic films, each just nanometers in thickness. These micro-SOFCs usually incorporate platinum electrodes, but they can be expensive and unreliable.

"If you use porous metal electrodes," explains Ramanathan,"they tend to be inherently unstable over long periods of time. They start to agglomerate and create open circuits in the fuel cells."

Ramanathan's platinum-free micro-SOFC eliminates this problem, resulting in a win-win: lower cost and higher reliability.

In a second paper published this month, the team demonstrated a methane-fueled micro-SOFC operating at less than 500° Celsius, a feat that is relatively rare in the field.

Traditional SOFCs have been operating at about 800-1000°C, but such high temperatures are only practical for stationary power generation. In short, using them to power up a smartphone mid-commute is not feasible.

In recent years, materials scientists have been working to reduce the required operating temperature to about 300-500°C, a range Ramanathan calls the"sweet spot."

Moreover, when fuel cells operate at lower temperatures, material reliability is less critical -- allowing, for example, the use of less expensive ceramics and metallic interconnects -- and the start-up time can be shorter.

"Low temperature is a holy grail in this field," says Ramanathan."If you can realize high-performance solid-oxide fuel cells that operate in the 300-500°C range, you can use them in transportation vehicles and portable electronics, and with different types of fuels."

The use of methane, an abundant and cheap natural gas, in the team's SOFC was also of note. Until recently, hydrogen has been the primary fuel for SOFCs. Pure hydrogen, however, requires a greater amount of processing.

"It's expensive to make pure hydrogen," says Ramanathan,"and that severely limits the range of applications."

As methane begins to take over as the fuel of choice, the advances in temperature, reliability, and affordability should continue to reinforce each other.

"Future research at SEAS will explore new types of catalysts for methane SOFCs, with the goal of identifying affordable, earth-abundant materials that can help lower the operating temperature even further," adds Ramanathan.

Fuel cell research at SEAS is funded by the same NSF grant that enabled the"Robobees" project led by Robert J. Wood, Assistant Professor of Electrical Engineering. Wood and Ramanathan hope that micro-SOFCs will provide the tiny power source necessary to get the flying robots off the ground.

Ramanathan's co-authors on the papers were Bo Kuai Lai, a Research Associate at SEAS, and Ph.D. candidate Kian Kerman '14.

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New Breed of Space Vehicle: Researchers Developing Conceptual Design for a Mars 'Hopper'

Their research findings have been published this month by theProceedings of the Royal Society A.

Robots exploring Mars can carry scientific instruments that measure the physical and chemical characteristics of the Martian surface and subsurface, analyse the environment and look for evidence of past or present life. Wheeled rovers have made extraordinary discoveries despite only exploring a small fraction of the planet.

The research has an international flavour. The University of Leicester has been working with a number of collaborators including Astrium Ltd in the UK and Center for Space Nuclear Research, Idaho, USA. The focus in the UK has been the development of a large-scale (400 kg) Mars Hopper concept that can fly in 1km 'hops'. This is an exciting concept that should be considered further as a complement to rover and orbital missions.

The Hopper can collect fuel between hops by compressing gas from the Martian atmosphere and can fly quickly between sites, powered by a long-life radioisotope power source. It could therefore study hundreds of locations over a lifetime of several years.

The Leicester research focused on the rocket motor, looking at its size and materials.

Dr Richard Ambrosi, at the Leicester Space Research Centre, commented:

"The improved mobility and range of a hopping vehicle will tell us more about the evolution of Mars and of the Solar System and may answer questions as to whether there was life in the past, whether Mars was wetter in the past and if so where that water went."

Dr Nigel Bannister added:"The Hopper is different from other rovers because of its power source. In one mode the heat source generates electric power to drive a compressor to gather the carbon dioxide propellant from the Martian atmosphere. The heat source then stores thermal energy and injects it into the propellant, which is accelerated out of a rocket nozzle to provide thrust."

Dr Hugo Williams said:"At Leicester we have concentrated on the motor and design features which translate into the performance of the vehicle.

"Our findings have resulted in a hop range of 1km, for a relatively large vehicle with a large suite of scientific instruments on board. We also looked at the geometry and the best materials for the motor core.

"Our interest in the materials aspect is particularly relevant because we are also engaged in collaborative research with our colleagues in Materials Engineering here at Leicester, and Queen Mary University of London to explore how material properties of materials for use in the space nuclear systems of the future can be enhanced through novel processing and manufacturing techniques."

A Royal Society interview with Dr Richard Ambrosi, Dr Hugo Williams and Dr Nigel Bannister is available online at:http://rspa.royalsocietypublishing.org/content/early/2010/11/11/rspa.2010.0438/suppl/DC2

A video illustrating the concept of the Mars vehicle is available on YouTube at:http://www.youtube.com/watch?v=grffBimdwUg

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