Are Electric Vehicles Poised for Their ‘Model T’ Moment?

When automobiles first debuted in the United States, they faced a classic “chicken and egg” problem. On one hand, autos were custom-made luxury items, affordable only to a niche market of affluent individuals. 

On the other hand, there was little incentive for most people to buy automobiles in the first place, as the system of roads in America was woefully underdeveloped.

Henry Ford managed to solve the “chicken and egg” problem with the Model T, the first product of its kind to reach the mass market. But today, there’s also another auto industry visionary facing a similar challenge in the 21st century: Elon Musk and his company, Tesla.

SIMILAR TRACKS

Ford’s assembly line and uncomplicated design allowed for cheaper pricing, which helped Ford sales to take off. With many new Model Ts hitting the road, the United States government was able to generate enough revenue from gasoline taxes to enable the sustainable development of roads in the United States.

More roads meant a renewed desire for more Model Ts to populate those roads, and so on. This was the start of a trend that sees 253 million cars on American roads a century later.

COST AND INFRASTRUCTURE: DUELING PRIORITIES

Fast-forward to today, and vehicle buyers have concerns not unlike those of early automobile adopters at the turn of the 20th century. Aside from the price of purchasing a new vehicle, most prospective buyers of electric vehicles cite charging availability and maximum travelling range as their biggest challenges.

Fortunately, EV prices are already falling due to advancements in the production of one of their key components: the lithium-ion battery packs that power them.

At one point, battery packs made up one-third of the costs for a new vehicle, but battery costs have dropped precipitously since 2010. That said, automakers like Tesla will need to continue to make progress here if they hope to match the growth and saturation of their forebears at the turn of the 20th century.

CHARGING AHEAD OF DEMAND
A study by the National Science Foundation’s INSPIRE Project found that the current amount of money disbursed as tax credits to new electric vehicle buyers (currently up to $7,500 per vehicle) would have been sufficient to build 60,000 new charging points nationwide.

The growth of charging station infrastructure is already astonishing. New public outlets have been added at a 65.3% CAGR between 2011 and 2016, and further growth will open even more roads to long-distance EV travel and network effects.

According to the math of the study, new charge stations would have a bigger effect on the EV market than the tax credits, and could have increased EV sales by five times the amount.

In short, charging stations will be to Tesla what roads were to Ford: the means by which they can reach lofty new heights of market dominance. Infrastructure development may be the “push” that electric vehicles need to get them over the early adoption barrier and into the mainstream. Combined with falling costs and improved efficiency, electric vehicles could create a Ford-like transformation within the automotive industry in a very short time.

** Article by C. Matel of the Visual Capitalist 

Turning Seawater into Drinking Water ~ Graphene Sieves May Hold the Key

A graphene membrane. Credit: The University of Manchester

 

“By 2025 the UN expects that 14% of the world’s population will encounter water scarcity.”

Graphene-oxide membranes have attracted considerable attention as promising candidates for new filtration technologies. Now the much sought-after development of making membranes capable of sieving common salts has been achieved.

New research demonstrates the real-world potential of providing clean drinking water for millions of people who struggle to access adequate clean water sources.

The new findings from a group of scientists at The University of Manchester were published today in the journal Nature Nanotechnology. Previously graphene-oxide membranes have shown exciting potential for gas separation and water filtration.

Graphene-oxide membranes developed at the National Graphene Institute have already demonstrated the potential of filtering out small nanoparticles, organic molecules, and even large salts. Until now, however, they couldn’t be used for sieving common salts used in desalination technologies, which require even smaller sieves.

Previous research at The University of Manchester found that if immersed in water, graphene-oxide membranes become slightly swollen and smaller salts flow through the membrane along with water, but larger ions or molecules are blocked.

The Manchester-based group have now further developed these graphene membranes and found a strategy to avoid the swelling of the membrane when exposed to water. The pore size in the membrane can be precisely controlled which can sieve common salts out of salty water and make it safe to drink.

As the effects of climate change continue to reduce modern city’s water supplies, wealthy modern countries are also investing in desalination technologies. Following the severe floods in California major wealthy cities are also looking increasingly to alternative water solutions.

World Economic Forum: Can Graphene Make the World’s Water Clean?

 

 

 

 

When the common salts are dissolved in water, they always form a ‘shell’ of water molecules around the salts molecules. This allows the tiny capillaries of the graphene-oxide membranes to block the salt from flowing along with the water. Water molecules are able to pass through the membrane barrier and flow anomalously fast which is ideal for application of these membranes for desalination.

Professor Rahul Nair, at The University of Manchester said: “Realisation of scalable membranes with uniform pore size down to atomic scale is a significant step forward and will open new possibilities for improving the efficiency of desalination technology.

“This is the first clear-cut experiment in this regime. We also demonstrate that there are realistic possibilities to scale up the described approach and mass produce graphene-based membranes with required sieve sizes.”

Mr. Jijo Abraham and Dr. Vasu Siddeswara Kalangi were the joint-lead authors on the research paper: “The developed membranes are not only useful for desalination, but the atomic scale tunability of the pore size also opens new opportunity to fabricate membranes with on-demand filtration capable of filtering out ions according to their sizes.” said Mr. Abraham.

By 2025 the UN expects that 14% of the world’s population will encounter water scarcity. This technology has the potential to revolutionize water filtration across the world, in particular in countries which cannot afford large scale desalination plants.

It is hoped that graphene-oxide membrane systems can be built on smaller scales making this technology accessible to countries which do not have the financial infrastructure to fund large plants without compromising the yield of fresh water produced.

Explore further: Researchers develop hybrid nuclear desalination technique with improved efficiency

More information: Tunable sieving of ions using graphene oxide membranes, Nature Nanotechnology, nature.com/articles/doi:10.1038/nnano.2017.21

Journal reference: Nature Nanotechnology

Provided by: University of Manchester

Can Quantum Dots Revolutionize Solar Power?

The sun will hopefully be the energy source of the future, but currently, solar power provides less than 1% of global energy. The reason isn’t due to a conspiracy among fossil fuel companies, as some media outlets apparently believe, but because of multiple inherent problems with solar technology. In a nutshell, there is a tradeoff between efficiency and cost.

For example, the current world-record for efficiency (i.e., the ability to convert light into electricity) is 44.7%, held by a multi-junction solar cell used in concentrated photovoltaics. However, for various reasons, such systems are still expensive. Cheaper solar cells, such as the ones you can mount on your roof, are more reasonably priced but have efficiences only around 10 to 20%. Thus, the “holy grail” is to design a solar cell with high efficiency and low cost.

One possible avenue is a design referred to as a dye-sensitized solar cell (DSSC). (Here is a video explaining how DSSCs work.) In a DSSC, dye molecules attached to titanium dioxide absorb photons and release electrons, creating an electric current.

Now, researchers from South Korea have added mobile quantum QTM -0.64% dots to the mix. Quantum dots (QDs) are nanoparticles that have a unique feature: They are able to generate more than one electron for every photon that is absorbed, a phenomenon known as “multiple exciton generation.” QD-DSSCs, therefore, have a higher efficiency than regular DSSCs. (See figure.)

As shown above, DSSCs containing red quantum dots (R-QD) were the best at increasing both light absorption and external quantum efficiency (a measure of how many electrons are generated per photon absorbed).

The authors told RealClearScience in an e-mail that the maximum efficiency of their system is 8.83%, which is obviously lower than most existing solar cell technologies. However, DSSCs are relatively cheap to produce, and with further research, they believe that they can crank up the efficiency way past 33.7% (the Shockley-Queisser limit, which is a theoretical limit on the efficiency of single junction solar cells).

Techies and investors should keep an eye on this emerging technology.

This article originally appeared on RealClearScience.

Source: Gede Widia Pratama Adhyaksa, Ga In Lee, Se-Woong Baek, Jung-Yong Lee & Jeung Ku Kang. “Broadband energy transfer to sensitizing dyes by mobile quantum dot mediators in solar cells.” Scientific Reports 3, Article number: 2711. Published 19-September-2013. doi:10.1038/srep02711

Regulating Electron ‘Spin’ Key to Making Organic Solar Cells Competitive

Aug. 7, 2013 — Organic solar cells, a new class of solar cell that mimics the natural process of plant photosynthesis, could revolutionise renewable energy — but currently lack the efficiency to compete with the more costly commercial silicon cells.

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At the moment, organic solar cells can achieve as much as 12 per cent efficiency in turning light into electricity, compared with 20 to 25 per cent for silicon-based cells.

This is the laser set-up used to to make the actual measurements reported in the paper. (Credit: Dr. Akshay Rao)

Now, researchers have discovered that manipulating the ‘spin’ of electrons in these solar cells dramatically improves their performance, providing a vital breakthrough in the pursuit of cheap, high performing solar power technologies.

The study, by researchers from the Universities of Cambridge and Washington, is published today in the journal Nature, and comes just days after scientists called on governments around the world to focus on solar energy with the same drive that put a man on the moon, calling for a “new Apollo mission to harness the sun’s power.”

Organic solar cells replicate photosynthesis using large, carbon-based molecules to harvest sunlight instead of the inorganic semiconductors used in commercial, silicon-based solar cells. These organic cells can be very thin, light and highly flexible, as well as printed from inks similar to newspapers — allowing for much faster and cheaper production processes than current solar cells.

But consistency has been a major issue. Scientists have, until now, struggled to understand why some of the molecules worked unexpectedly well, while others perform indifferently.

Researchers from Cambridge’s Cavendish Laboratory developed sensitive laser-based techniques to track the motion and interaction of electrons in these cells. To their surprise, the team found that the performance differences between materials could be attributed to the quantum property of ‘spin’.

‘Spin’ is a property of particles related to their angular momentum, with electrons coming in two flavours, ‘spin-up’ or ‘spin-down’. Electrons in solar cells can be lost through a process called ‘recombination’, where electrons lose their energy — or “excitation” state — and fall back into an empty state known as the “hole.”

Researchers found that by arranging the electrons ‘spin’ in a specific way, they can block the energy collapse from ‘recombination’ and increase current from the cell.

“This discovery is very exciting, as we can now harness spin physics to improve solar cells, something we had previously not thought possible. We should see new materials and solar cells that make use of this very soon” said Dr. Akshay Rao, a Research Fellow at the Cavendish Laboratory and Corpus Christi College, Cambridge, who lead the study with colleagues Philip Chow and Dr. Simon Gélinas.

The Cambridge team believe that design concepts coming out of this work could help to close the gap between organic and silicon solar cells, bringing the large-scale deployment of solar cells closer to reality. In addition, some of these design concepts could also be applied to Organic Light Emitting diodes, a new and rapidly growing display technology, allowing for more efficient displays in cell phones and TVs

Sun Plus Nanotechnology: Can Solar Energy Get Bigger by Thinking Small?

Patrick J. Kiger

For National Geographic News

Published April 28, 2013

“Advances in nanotechnology will lead to higher efficiencies and lower costs, and these can and likely will be significant,” explains Matt Beard, a senior scientist for the U.S. Department of Energy‘s National Renewable Energy Laboratory (NREL). “In fact, nanotechnology is already having dramatic effects on the science of solar cells.”

 

Nearly 60 years after researchers first demonstrated a way to convert sunlight into energy, science is still grappling with a critical limitation of the solar photovoltaic cell.

It just isn’t that efficient at turning the tremendous power of the sun into electricity.

And even though commercial solar cells today have double to four times the 6 percent efficiency of the one first unveiled in 1954 by Bell Laboratories in New Jersey, that hasn’t been sufficient to push fossil fuel from its preeminent place in the world energy mix.

But now, alternative energy researchers think that something really small—nanotechnology, the engineering of structures a fraction of the width of a human hair—could give a gigantic boost to solar energy. (Related Quiz: “What You Don’t Know About Solar Power“)

“Advances in nanotechnology will lead to higher efficiencies and lower costs, and these can and likely will be significant,” explains Matt Beard, a senior scientist for the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL). “In fact, nanotechnology is already having dramatic effects on the science of solar cells.”

Of course, the super-expensive solar arrays used in NASA’s space program are far more efficient than those installed on rooftops. (Related: “Beam It Down: A Drive to Launch Space-Based Solar“) And in the laboratory, scientists have achieved record-breaking efficiencies of more than 40 percent. But such contests are a testament to the gap between solar potential and the mass market cells of today.

 

The light glinting off the surface of this solar photovoltaic cell signifies lost efficiency. Scientists are looking to nanotechnology to boost solar power, including by reducing the amount of sunlight that silicon wastes through reflection.

The power output of the Sun that reaches the Earth could provide as much as 10,000 times more energy than the combined output of all the commercial power plants on the planet, according to the National Academy of Engineering. The problem is how to harvest that energy.

Today’s commercial solar cells, usually fashioned from silicon, are still relatively expensive to produce (even though prices have come down), and they generally manage to capture only 10 to 20 percent of the sunlight that strikes them. This contributes to the high cost of solar-generated electricity compared to power generated by conventional fossil-fuel-burning plants. By one comparative measure, the U.S. Energy Information Administration estimated the levelized cost of new solar PV as of 2012 was about 56 percent higher than the cost of generation from a conventional coal plant.

Nanotechnology may provide an answer to the efficiency problem, by tinkering with solar power cells at a fundamental level to boost their ability to convert sunlight into power, and by freeing the industry to use less expensive materials. If so, it would fulfill the predictions of some of nanotechnology’s pioneers, like the late Nobel physicist Richard Smalley, who saw potential in nanoscale engineering to address the world’s energy problems. (See related: “Nano’s Big Future“) Scientists caution that there’s still a lot of work ahead to overcome technical challenges and make these inventions ready for prime time. For example, more research is needed on the environmental, health, and safety aspects of nano-materials, said the National Academy of Sciences in a 2012 report that looked broadly at nanotechnology, not at solar applications in particular. (Related Pictures: “Seven Ingredients for Better Car Batteries.”)

But Luke Henley, a University of Illinois at Chicago chemistry professor who received a 2012 National Science Foundation grant to develop a solar-related nanotechnology project, predicts there will be major advances over the next five to 10 years. “It’s potentially a game changer,” he says. Here are five intriguing recent nanotechnology innovations that could help to boost solar power.

Billions of Tiny Holes

To reduce the amount of sunlight that is reflected away from silicon solar cells and wasted, manufacturers usually add one or more layers of antireflective material, which significantly boosts the cost. But late last year, NREL scientists announced a breakthrough in the use of nanotechnology to reduce the amount of light that silicon cells reflect. It involves using a liquid process to put billions of nano-sized holes in each square inch of a solar cell’s surface. Since the holes are smaller than the light wavelengths hitting them, the light is absorbed rather than reflected. The new material, which is called “black silicon,” is nearly 20 percent more efficient than existing silicon cell designs. (Related photos: “Spanish Solar Energy“)

The “Nano Sandwich”

Organic solar cells, made from elements such as carbon, nitrogen, and oxygen that are found in living things, would be cheaper and easier to make than current silicon-based solar cells. The tradeoff, until now, is that they haven’t been as efficient. But a team of Princeton University researchers, led by electrical engineer Stephen Chou, has been able to nearly triple the efficiency of solar cells by devising a nanostructured “sandwich” of metal and plastic. In technical lingo, their invention is called a plasmodic cavity with subwavelength hole array, or PlaSCH. It consists of a thin strip of plastic sandwiched between a top layer made from an incredibly fine metal mesh and a bottom layer of the metal film used in conventional solar cells.

All aspects of the solar cell’s structure—from its thickness to the spacing of the mesh and diameter of the holes—are smaller than the wavelength of the light that it collects. As a result, the device absorbs most of the light in that frequency rather than reflecting it. “It’s like a black hole for light,” Chou explained in a Princeton press release in December. “It traps it.” Another plus: researchers say the PlaSCH cells can be manufactured cost-effectively in sheets, using a process developed by Chou years ago that embosses the nanostructures over a large area, similar to the way newspapers are printed.

Mimicking Evolution

One of the big difficulties in coming up with more energy-efficient solar cells is the limitations of the researchers’ own imaginations. But in a January 2013 article published in Scientific Reports, Northwestern University mechanical engineering professor Wei Chen and graduate student Cheng Sun introduced a method that might be superior to human brainstorming. Using a mathematical search algorithm based on natural biological evolution, they took dozens of design elements and then “mated” them over a series of 20 generations, in a process that mimicked the evolutionary principles of crossover and genetic mutation.

“Our approach is based upon the biologically evolutionary process of survival of the fittest,” Chen explained in an article on Northwestern University’s website.

The result: An evolution-inspired organic solar cell—that is, one that uses carbon-based materials rather than silicon crystals–in which light first enters a 100-nanometer-thick scattering layer with an unorthodox geometric pattern. The researchers say this should enable it to absorb light more efficiently. The U.S. Department of Energy’s Argonne National Laboratory will fabricate an actual working version of the new cell for testing.

Tiny Antennae

We’re used to thinking of solar energy as something that we collect with panels. But even the latest-generation silicon panels can take in light from only a relatively narrow range of frequencies, amounting to about 20 percent of the available energy in the sun’s rays. The panels then require separate equipment to convert the stored energy to useable electricity. But researchers at the University of Connecticut and Penn State  are working on an entirely new approach, using tiny, nanoscale antenna arrays, which would take in a wider range of frequencies and collect about 70 percent of the available energy in sunlight. Additionally, the antenna arrays themselves could convert that energy to direct current, without need for additional gear.

Scientists have been thinking about using tiny antennae for a while, but until recently, they lacked the technology make them work, since such a setup would require electrodes that were just one or two nanometers apart—about 1/30,000 the width of a human hair. Fortunately, University of Connecticut engineering professor Brian Willis has developed a fabrication technique called selective area atomic-layer deposition, which makes it possible to coat the electrodes with layers of individual copper atoms, until they are separated by just 1.5 nanometers. “This new technology could get us over the hump and make solar energy cost-competitive with fossil fuels,” Willis explained in February. “This is brand new technology, a whole new train of thought.”

Solar-Collecting Paint

No matter what sort of solar energy-collecting technology you employ, there’s still the problem of building a bunch of the devices and hooking them up in places with sun exposure. But University of Southern California chemistry professor Richard L. Brutchey and postdoctoral researcher David H. Webber have devised a technology that could turn a building into a solar collector.

They’ve created a stable, electricity-conducting liquid filled with solar-collecting nanocrystals, which can be painted or printed like an ink onto surfaces such as window glass or plastic roof panels. The nanocrystals, made of cadmium selenide instead of silicon, are about four nanometers in size—about 250 billion of them could fit on the head of a pin—so they are capable of floating in a liquid solution.  (Related Pictures: “A New Hub for Solar Tech Blooms in Japan“)

Brutchey’s and Webber’s secret to getting the technology to work? Finding an organic molecule that could attach to the nanocrystals and stabilize them and prevent them from sticking together, without hindering their ability to conduct electricity.

The researchers aim to work on nanocrystals built from materials other than cadmium, a toxic metal. “While the commercialization of this technology is still years away, we see a clear path forward toward integrating this into the next generation of solar cell technologies,” Brutchey says. (Related video: “Toxic Land Generates Solar Power“)

Quantum Dots for Next Generation Photovoltaics

25 November 2012 Octavi E. Semonin, Joseph M. Luther, and Matthew C. Beard

Beard et al. discuss the current status of research efforts towards utilizing the unique properties of colloidal quantum dots for solar photon conversion.

Colloidal quantum-confined semiconductor nanostructures are an emerging class of functional material that are being developed for novel solar energy conversion strategies. One of the largest losses in a bulk or thin film solar cell occurs within a few picoseconds after the photon is absorbed, as photons with energy larger than the semiconductor bandgap produce chargecarriers with excess kinetic energy, which is then dissipated via phonon emission. Semiconductor nanostructures, where at least one dimension is small enough to produce quantum confinement effects, provide new pathways for controlling energy flow and therefore have the potential to increase the efficiency of the primary photoconversion step. In this review, we provide the current status of research efforts towards utilizing the unique properties of colloidal quantum dots (nanocrystals confined in three dimensions) in prototype solar cells and demonstrate that these unique systems have the potential to bypass the Shockley-Queisser single-junction limit for solar photon conversion.

Nanomaterials form a flexible material platform that has great promise for providing new ways to approach solar energy conversion. The synthesis, investigation, and utilization of these novel nanostructures lie at the interface between chemistry, physics, materials science, and engineering. The chemistry community is providing simple and safe solution phase syntheses that yield monodisperse, passivated nanocrystals (NCs) of high optoelectronic quality with a growing degree of control over composition, shape, and structure.

These novel structures provide physicists and materials scientists with new avenues towards controlling energy flow. One of the largest scientific challenges regarding solar energy conversion is increasing the efficiency of the primary photoconversion process. In recent years we have studied the process of multiple exciton generation (MEG), where a photon bearing at least twice the energy of the bandgap can produce two or more electron-hole pairs and thereby bypass some wasteful heat production. 1,2

Third generation photovoltaics and multiple exciton generation

Traditional solar cells only harvest a fixed amount of energy from any given solar photon. However, the solar spectrum consists of photons with energies spanning 0.4 eV to 4.0 eV (see Fig. 1). The band-gap of the semiconductor determines how much solar energy can be converted to electrical power: photons with energy less than the bandgap are not absorbed, while photons with energy greater than the bandgap lose excess energy unnecessarily via emission of phonons (thermalization). Fig. 1 shows that the available free energy from an ideal present day single junction cell is about 33 %, while another 33 % is lost to thermalization and the remaining third is divided up between photons not absorbed and unavoidable thermodynamic losses. Those losses are associated with extracting photoexcited electrons at the contacts prior to radiative recombination.

Future directions and challenges

Surpassing the SQ limit for single junction solar cells is both a scientific and technological challenge and the use of semiconductor NCs to enhance the primary photoconversion process is a promising avenue towards such a goal. The MEG result is remarkable not only as a conclusive demonstration of MEG, but also as a demonstration that the ‘extra’ carriers can be collected in a suitable quantum dot solar cell. Thus, one of the tenets of the SQ limit, that high-energy photons only produce one electron-hole pair in a semiconductor, can be bypassed. However, the present day MEG solar cell only benefits by about 4 % in its photocurrent from collection of multiple excited carriers per photon. The challenge now is to further improve the MEG efficiency, as well as to continue to improve the fundamental QD film and device architecture. One avenue of future research is to explore MEG in a variety of shapes, compositions, and structures. Quantum wires or rods (QRs) with two-dimensional confinement, and quantum platelets (QPs) with one-dimensional confinement both are relatively unexplored, and QRs have already given some promising results that show further enhancement of MEG.

Other approaches to high-efficiency devices, most notably multijunction solar cells, are very promising avenues as well. However, in order for any of these approaches to be effective, a fundamentally well-controlled material is essential. As Kramer and Sargent propose, carrier mobility, trap density, and trap level position are useful metrics to use in this vein. We would also add that the carrier lifetime (which is intrinsically related to trap density) is an accessible and important parameter to monitor in this endeavor.

The diffusion length, determined from the product of lifetime and mobility, will determine how thick efficient cells can be made before recombination dominates. This length, presently around 100 nm, must be extended to the length scales of optical and NIR absorption lengths (about one micron).

Acknowledgements

We are thankful for the support of the division of Chemical, Geoscience and Biosciences, within the office of Basic Energy Sciences, office of Science, US Department of Energy for the work on the photophysics and chemistry of quantum dots. Our work on quantum dot solar cells was supported as part of the Center for Advanced Solar Photophysics an Energy Frontier Research Center within the office of Basic Energy Sciences, Office of Sciences, US DOE. Funding was provided to NREL under contract number DE-AC36-086038308 with DOE.

*** This report has been edited for length. If you wish to read the full report, go here:

http://edition.pagesuite-professional.co.uk/Launch.aspx?EID=a1ed4eca-e2e3-4beb-a7e3-13d584504db8&pnum=46

 

Building design and the potential of third-generation solar cells

Ingo B Hagemann

Note To Readers: The potential of this technology IOHO gives a whole new definition to the term “Smart Building”. “Great moments are born from Great Opportunity.” (H.Brooks: 1980 “Miracle”)

Ingo B Hagemann, architect and building-integrated photovoltaic (BIPV) consultant, discusses opportunities and challenges for organic solar cells and other third-generation photovoltaic (third-gen PV) technologies in the building and construction industry.

Until now, PVs have been developed and perceived simply as systems for generating electricity, with the performance of cells being defined purely in terms of power output.

However, this is changing. In the future solar electricity production will become a by-product of multifunctional building components with integrated PV capability. Beside solar power output, the technology will be judged on other criteria, such as design and structural integration flexibility.

Organic PVs (OPVs) and dye-sensitised solar cells (DSSCs), which are collectively referred to as third-generation PV technologies (third-gen), have the potential to contribute significantly to this development. As third-gen PV technology advances in terms of performance and other factors, architecturally attractive uses of PVs in the building fabric will become more commonplace.

Unlike bulky and rigid traditional, silicon-based solar cells, third-gen PVs can be made lightweight, flexible and translucent. They can be produced in different colours and patterned, resulting in additional smart design opportunities for the integration of the PV into the building shell.

The new design features of third-gen PV correspond well with current trends in architectural design, such as an intensive use of colours, the use of (multimedia) screens and patterns for building façade designs. The technology also supports the rediscovery of the moulding of complex curving forms, which is a result and expression of contemporary architectural practice in which digital technologies are radically changing the way how buildings are conceived, designed and produced.

Printing, coating, vacuum processing and other simple, low-temperature and low-cost production processes are being developed to fabricate third-gen PVs, which will make them less costly to manufacture.

The benefits and advantages of third-gen PV for building and construction applications can be separated in to five main areas:

Good power performance under dim or variable lighting conditions

The power output of third-gen PV technologies is not so dependent on the access of direct solar radiation, compared with silicon, suggesting high performance under low light conditions such as fog, partially shaded building surface areas or indoors. This makes third-gen PV an ideal candidate for cloudy or smoggy environments such as major built up cities, where low light conditions are commonplace; in equatorial areas, where lots of clouding is caused by the Intertropical Convergence Zone (ITCZ); or in high latitudes, where overcast skies are typical. In addition, third-gen PVs can be developed for certain types of indoor applications, like powering emergency lights or motion detectors.

Power performance without cooling

Power performance without cooling means third-gen PVs can be used as an integral part of ‘sandwich’ building elements, which do not usually provide the option of back-ventilation for the integrated PV.

Sandwich elements allow for a wide variety of material combinations. Several variations are used in the building industry. Examples are structural insulated panels (SIPs), precast insulated roof systems – used often in home construction – or floor-to floor façade elements used for the bracing of curtain wall façade systems.

Together with modern construction processes using assembly line automation, prefab sandwich elements meet today’s requirements of fast installation processes and heat insulation, while allowing for high standards of accuracy.

 

Design flexibility due to low-cost materials and easy-to-handle processing technologies

The global construction industry is diverse and the types of building products and materials it uses vary considerably. Construction methods and traditions, building products and building codes differ from country to country, even region to region. Unlike standard PV modules, it is not possible to design building products – with or without integrated PV – likely to serve a market on a global scale. However as third-gen PVs could be made using more straightforward, low-temperature production methods such as roll-to-toll on flexible substrates, the financial and technological effort needed to make these cells is much lower, compared with established first- and second-gen crystal and thin-film PV cells.

Therefore third-gen PV has the potential to open up the market for building-integrated PV products that serve the needs of regional building markets.

Transparency and durability

Glass is one of the most popular and durable building materials today, allowing for buildings to be designed with large window openings to exploit natural light. Glass can be engineered to meet the increasing façade performance expectations of the building envelope, with regards to heat insulation (U-value), noise, sun protection and weather protection and durability.

Rapid developments in the field of new coatings for glass, new material combinations with glass and associated new engineering, production and construction methods ensure it will continue to be a key component in building construction. In addition glass has a relatively small impact on the environment.

Essentially, minerals are used to produce a benign product. Theoretically, glass is infinitely recyclable with no loss of quality. These features make it a first-class, ecological building product for today and tomorrow.

Flexible and lightweight

Third-gen PV made from flexible and transparent substrates and encapsulation materials can provide a product with a combination of performance characteristics that do not yet exist on the building market. So-called plastic OPV cells can be lightweight, translucent and available in different colours, such as Konarka’s Power Plastic. OPvs offer integration opportunities for all kinds of building structures where a lightweight form factor is of structural importance, such as canopies and awnings, light roof construction of factory buildings and sports stadiums.

A field of special interest for the application of this type of third-gen PV is tension membrane or pneumatic cushions structures, which have increased in importance in modern architecture. They exploit daylight, while at the same time sheltering large façade areas. At night, PV structures could be illuminated by LED lights and designed to catch the attention of the public like other multimedia façades.

These low resource-demanding structures satisfy aspects of modern and sustainable architecture and third-gen PV solar electricity production adds functionality without interfering in design elements and properties. Well-known examples of these structures – without PV – are the Allianz Arena in Munich, the façade of the Burj Al Arab in Dubai, or the Olympic Swim Stadium in Beijing, China.

Challenges

Despite these advantages, third-gen PV efficiencies lack in comparison to conventional PV. But it can be expected that further technology improvements will increase over the next few years. Low production costs will help to neutralise low efficiency issues, since there are applications for BIPV where cost is the prime concern – such as the coating of large quantities of glass or the covering of large building surface areas with one type of material only.

A bigger challenge is improving the relatively short lifetimes of third-gen PVs. Due to established cycles for the renovation of building exteriors as well as liability issues – which architects, consulting engineers and construction companies must adhere to – the lifetime of BIPV product components must achieve 20-30 years.

In conclusion, the anticipated novel design opportunities and technical performance characteristics associated with third-gen PVs make them especially attractive for architectural applications. However, it also needs to be made clear that any meaningful integration of these technologies in the building fabric will only arise from holistic planning and design approaches, which link the necessary power-engineering demands to the numerous existing and increasing requirements for building enclosures, architectural design and urban planning.

The properties desirable for a solar cell as part of an integrated structural product must be specified and consistently developed. The development of such BIPV products needs application-oriented research, to ensure products are meet practical requirements in a building.

The first- and seconnd-generation PV industry is still focused on bulk production, to benefit from mass production. But to meet the demands of an upcoming BIPV market, the low cost and flexibility of third-gen PV production provides a unique opportunity for the PV industry to make a transition to flexible production processes. Such a step would allow the PV industry to offer a structural and design flexibility for their BIPV products, which will provide architects the opportunity to create individual and alternating BIPV designs solutions

Installed price of solar photovoltaic systems in the U.S. continues to decline at a rapid pace

(Nanowerk News) The installed price of solar  photovoltaic (PV) power systems in the United States fell substantially in 2011  and through the first half of 2012, according to the latest edition of Tracking the Sun (“Tracking the Sun V: An Historical Summary of the Installed Price  of Photovoltaics in the United States from 1998 to 201”; pdf), an annual PV  cost-tracking report produced by the Department of Energy’s Lawrence Berkeley  National Laboratory (Berkeley Lab).
The  median installed price of residential and commercial PV systems completed in  2011 fell by roughly 11 to 14 percent from the year before, depending on system  size, and, in California, prices fell by an additional 3 to 7 percent within the  first six months of 2012. These recent installed price reductions are  attributable, in large part, to dramatic reductions in PV module prices, which  have been falling precipitously since 2008.

The  report indicates that non-module costs—such as installation labor, marketing,  overhead, inverters, and the balance of systems—have also fallen significantly  over time.  “The drop in non-module costs is especially important,” notes report  co-author Ryan Wiser of Berkeley Lab’s Environmental Energy Technologies  Division, “as these costs can be most readily influenced by local, state, and  national policies aimed at accelerating deployment and removing market  barriers.” According to the report, average non-module costs for residential and  commercial systems declined by roughly 30 percent from 1998 to 2011, but have  not declined as rapidly as module prices in recent years. As a result,  non-module costs now represent a sizable fraction of the installed price of PV  systems, and continued deep reduction in the price of PV will require concerted  emphasis on lowering the portion of non-module costs associated with so-called “business process” or “soft” costs.

The report indicates that the median installed price of PV  systems installed in 2011 was $6.10 per watt for residential and small  commercial systems smaller than 10 kilowatts (kW) in size and was $4.90/W for  larger commercial systems of 100 kW or more in size.  Utility-sector PV systems  larger than 2,000 kW in size averaged $3.40/W in 2011.  Report co-author Galen  Barbose, also of Berkeley Lab, stresses the importance of keeping these numbers  in context, noting that “these data provide a reliable benchmark for systems  installed in the recent past, but prices have continued to decline over time,  and PV systems being sold today are being offered at lower prices.”

Based on these data and on installed price data from other major  international PV markets, the authors suggest that PV prices in the United  States may be driven lower through large-scale deployment programs, but that  other factors are also important in achieving installed price reductions.

The market for solar PV systems in the United States has grown  rapidly over the past decade, as national, state and local governments offered  various incentives to expand the solar market and accelerate cost reductions.   This fifth edition in Berkeley Lab’s Tracking the Sun report series  describes historical trends in the installed price of PV in the United States,  and examines more than 150,000 residential, commercial, and utility-sector PV  systems installed between 1998 and 2011 across 27 states, representing roughly  76 percent of all grid-connected PV capacity installed in the United States.  Naïm Darghouth, also with Berkeley Lab, explains that “the study is intended to  provide policy makers and industry observers with a reliable and detailed set of  historical benchmarks for tracking and understanding past trends in the  installed price of PV.”

Prices Differ by Region and by Size and Type of  SystemThe study also highlights the significant variability in PV  system pricing, some of which is associated with differences in installed prices  by region and by system size and installation type. Comparing across U.S.  states, for example, the median installed price of PV systems less than 10 kW in  size that were completed in 2011 and ranged from $4.90/W to $7.60/W, depending  on the state.

It also shows that PV installed prices exhibit significant  economies of scale. Among systems installed in 2011, the median price for  systems smaller than 2 kW was $7.70/W, while the median price for large  commercial systems greater than 1,000 kW in size was $4.50/W.  Utility-scale  systems installed in 2011 registered even lower prices, with most systems larger  than 10,000 kW ranging from $2.80/W to $3.50/W.s

The report also finds that the installed price of residential PV  systems on new homes has generally been significantly lower than the price of  similarly sized systems installed as retrofits to existing homes, that building  integrated PV systems have generally been higher priced than rack-mounted  systems, and that systems installed on tax-exempt customer sites have generally  been priced higher than those installed at residential and for-profit commercial  customer sites.

Price Declines for PV System Owners in 2011 Were Offset  by Falling IncentivesState agencies and utilities in many regions offer rebates or  other forms of cash incentives for residential and commercial PV systems.   According to the report, the median pre-tax value of such cash incentives ranged  from $0.90/W to $1.20/W for systems installed in 2011, depending on system size.   These incentives have declined significantly over time, falling by roughly 80  percent over the past decade, and by 21 percent to 43 percent from just 2010 to  2011.  Rather than a direct cash incentive, some states with renewables  portfolio standards provide financial incentives for solar PV by creating a  market for solar renewable energy certificates (SRECs), and SREC prices have  also fallen dramatically in recent years.  These declines in cash incentives and  SREC prices have, to a significant degree, offset recent installed price  reductions, dampening any overall improvement in the customer economics of solar  PV.

In conjunction with this report, LBNL and the National Renewable  Energy Laboratory (NREL) have also issued a jointly authored summary report that  provides a high-level overview of historical, recent, and projected near-term PV  pricing trends in the United States.  That report summarizes findings on  historical price trends from LBNL’s Tracking the Sun V, along with several  ongoing NREL research activities to benchmark recent and current PV prices and  to track industry projections for near-term PV pricing trends.  The summary  report documents further installed price reductions for systems installed and  quoted in 2012.

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University of British Columbia Files Patent on Unique Battery Type Solar/Light Conversion Cell

SOURCE: University of British Columbia

November 02, 2012 11:30 ET

VANCOUVER, BC–(Marketwire – Nov 2, 2012) – The University of British Columbia (UBC)announces the international patent filing for a Battery type Solar/Light conversion cell. This unique generator and storage approach allows both solar power generation and storage within a single cell. Based on photosynthesis, it can be implemented using abundant and readily replenished and renewable biomaterials.

This invention aims to allow industry to install solar photovoltaic (PV) systems with a built in energy storage component. This type of system addresses the natural intermittency of Solar (PV) systems due to the movement of clouds over modules and the need for night time power, and it provides a built-in solution for reducing the total demand on the electrical grid. This unit is anticipated to provide a simple effective method for energy arbitrage by storing direct and indirect Solar/Light energy for later use should the peak energy demands fall several hours after the peak solar generation is available, such as at night. The commercialization of this technical achievement would allow for a much larger penetration of solar PV into the total energy supply and management system and therefore the invention has the potential to increase the value and market for both grid-connected and off-grid solar PV systems worldwide.

The invention is the result of an interdisciplinary venture led by Professor J. Thomas Beatty, who studies photosynthesis in micro-organisms, and Professor John D. Madden in Electrical & Computer Engineering. “We began by asking whether we can learn from nature and make use of natural materials to create useful solar energy harvesting approaches. What we found is an approach that integrates two key components of energy supply: generation and storage”.

The new approach involves the use of a light absorbing battery-like cell complete with two electrodes and an electrolyte. Light is absorbed by light harvesting molecules in the electrolyte. Charges are then transferred between the excited light harvesting molecules and mediator molecules, also in the electrolyte, with nearly perfect quantum efficiency. The mediators store the harvested energy, which can then be extracted at the electrodes on demand. Essential to the effectiveness of this technology is the development of highly selective electrodes, each of which primarily reacts with only one type of mediator.

“Unlike photovoltaic technologies, which rely on very thin absorbing layers, and transparent electrodes, this new technology operates with light arriving parallel to the surface of the electrodes, allowing for thicker devices with volume for energy storage,” says Madden. “With the new architecture one can envision the creation of solar ponds for harvesting and storage. This is a very general new approach.”

The UBC team is supported by Natural Sciences and Engineering Research Council of Canada. Researchers from the University of South Florida and the Australian Centre of Excellence in Electro materials Science are also involved.

The University of British Columbia, located in Vancouver, BC, is a global centre for research and teaching, consistently ranked among the top 40 universities of the world. UBC attracts $550 million per year in research funding from government, non-profit organizations and industry through more than 8,000 projects. It ranks in the top ten universities in North America for commercializing research and has spun off 149 companies. It is a place where innovative scientific ideas are transferred effectively to industry through a globally connected research community.

Solar Roadways: Powering the World of Tomorrow

Image via CrunchBase

 

Wed, 17 October 2012 22:38

 

Here’s a glimpse into the future: high maintenance, expensive concrete roads and parking lots turned into glossy solar surfaces, fuelling enough energy from the sun to power nearby communities and the electric vehicles above them.

 

According to inventors/creators of Solar Roadways, Scott and Julie Brusaw, sections of the road could be made out of solar cells to collect energy, which would more than pay for the cost of the panel. And what if LEDs were added beneath road lines for safer night time driving and heating elements were added to prevent snow/ice accumulation is northern climates? Those are questions the Solar Roadways project sought to answer under a 2009 Federal Highway Administration contract to build the first ever prototype.

 

Thus far, the results have proved favourable and the company was awarded a follow-up 2-year Phase II $750,000 SBIR contract in 2011 to build a prototype parking lot.

 

Is the surface safe for cars to drive on? Apparently, it’s safer than concrete, which collects a slick sheen of oil on its surface over time. The hardness of glass falls between steel and stainless steel. It’s also easier and faster to replace than cement.

 

Related Article: The Art of Solar War

 

Each road panel is made of three basic layers. The road surface layer is translucent and rough enough to provide great traction, capable of handling today’s heaviest loads under the absolute worst conditions. An electronics layer would control the heating element, lighting, communications and monitoring to create an intelligent highway system. The base plate layer would take the sun collected from the electronics layer and distribute it to homes and businesses connected to the roadway.

 

A remarkable idea come to life, the Solar Roadway could very well become one of the greatest infrastructure innovations of the 21st century. It’s time to upgrade.

 

By. Carin Hall of energydigitial.com

 

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