Tag: coal

Powered by the Sun: Boosting Solar Efficiency

solar1Improving the efficiency of solar power – which is currently the most promising alternative energy source – is central to ensuring that it an becomes economically viable replacement to fossil fuels, coal, and other “dirty” sources. And while many solutions have emerged in recent years that have led to improvements in solar panel efficiency, many developments are also aimed at the other end of things – i.e. improving the storage capacity of solar batteries.

In the former case, a group of scientists working with the University of Utah believe they’ve discovered a method of substantially boosting solar cell efficiencies. By adding a polychromat layer that separates and sorts incoming light, redirecting it to strike particular layers in a multijunction cell, they hope to create a commercial cell that can absorb more wavelengths of light, and therefor generate more energy for volume than conventional cells.

EMSpectrumTraditionally, solar cell technology has struggled to overcome a significant efficiency problem. The type of substrate used dictates how much energy can be absorbed from sunlight — but each type of substrate (silicon, gallium arsenide, indium gallium arsenide, and many others) corresponds to capturing a particular wavelength of energy. Cheap solar cells built on inexpensive silicon have a maximum theoretical efficiency of 34% and a practical (real-world) efficiency of around 22%.

At the other end of things, there are multijunction cells. These use multiple layers of substrates to capture a larger section of the sun’s spectrum and can reach up to 87% efficiency in theory – but are currently limited to 43% in practice. What’s more, these types of multijunction cells are extremely expensive and have intricate wiring and precise structures, all of which leads to increased production and installation costs.

SolarCellResearchIn contrast, the cell created by the University of Utah used two layers — indium gallium phosphide (for visible light) and gallium arsenide for infrared light. According to the research team, when their polychromat was added, the power efficiency increased by 16 percent. The team also ran simulations of a polychromat layer with up to eight different absorbtion layers and claim that it could potentially yield an efficiency increase of up to 50%.

However, there were some footnotes to their report which temper the good news. For one, the potential gain has not been tested yet, so any major increases in solar efficiency remain theoretical at this time. Second, the report states that the reported gain was a percentage of a percentage, meaning that if the original cell efficiency was 30%, then a gain of 16% percent means that the new efficiency is 34.8%. That’s still a huge gain for a polychromat layer that is easily produced, but not as impressive as it originally sounded.

PolyChromat-640x353However, given that the biggest barrier to multi-junction solar cell technology is manufacturing complexity and associated cost, anything that boosts cell efficiency on the front end without requiring any major changes to the manufacturing process is going to help with the long-term commercialization of the technology. Advances like this could help make technologies cost effective for personal deployment and allow them to scale in a similar fashion to cheaper devices.

In the latter case, where energy storage is concerned, a California-based startup called Enervault recently unveiled battery technology that could increase the amount of renewable energy utilities can use. The technology is based on inexpensive materials that researchers had largely given up on because batteries made from them didn’t last long enough to be practical. But the company says it has figured out how to make the batteries last for decades.

SONY DSCThe technology is being demonstrated in a large battery at a facility in the California desert near Modeso, 0ne that stores one megawatt-hour of electricity, enough to run 10,000 100-watt light bulbs for an hour. The company has been testing a similar, though much smaller, version of the technology for about two years with good results. It has also raised $30 million in funding, including a $5 million grant from the U.S. Department of Energy.

The technology is a type of flow battery, so called because the energy storage materials are in liquid form. They are stored in big tanks until they’re needed and then pumped through a relatively small device (called a stack) where they interact to generate electricity. Building bigger tanks is relatively cheap, so the more energy storage is needed, the better the economics become. That means the batteries are best suited for storing hours’ or days’ worth of electricity, and not delivering quick bursts.

solarpanelsThis is especially good news for solar and wind companies, which have remained plagued by problems of energy storage despite improvements in both yield and efficiency. Enervault says that when the batteries are produced commercially at even larger sizes, they will cost just a fifth as much as vanadium redox flow batteries, which have been demonstrated at large scales and are probably the type of flow battery closest to market right now.

And the idea is not reserved to just startups. Researchers at Harvard recently made a flow battery that could prove cheaper than Enervault’s, but the prototype is small and could take many years to turn into a marketable version. An MIT spinoff, Sun Catalytix, is also developing an advanced flow battery, but its prototype is also small. And other types of inexpensive, long-duration batteries are being developed, using materials such as molten metals.

Sumitomo-redox-flow-battery-YokohamaOne significant drawback to the technology is that it’s less than 70 percent efficient, which falls short of the 90 percent efficiency of many batteries. The company says the economics still work out, but such a wasteful battery might not be ideal for large-scale renewable energy. More solar panels would have to be installed to make up for the waste. What’s more, the market for batteries designed to store hours of electricity is still uncertain.

A combination of advanced weather forecasts, responsive fossil-fuel power plants, better transmission networks, and smart controls for wind and solar power could delay the need for them. California is requiring its utilities to invest in energy storage but hasn’t specified what kind, and it’s not clear what types of batteries will prove most valuable in the near term, slow-charging ones like Enervault’s or those that deliver quicker bursts of power to make up for short-term variations in energy supply.

Tesla Motors, one company developing the latter type, hopes to make them affordable by producing them at a huge factory. And developments and new materials are being considered all time (i.e. graphene) that are improving both the efficiency and storage capacity of batteries. And with solar panels and wind becoming increasingly cost-effective, the likelihood of storage methods catching up is all but inevitable.

Sources: extremetech.com, technologyreview.com

 

The Glucose Economy

hacking-bacteria-fuel-ecoli-670In the long search to find alternatives to fossil fuels and industrial processes that produce tons of waste, several ideas have been forward. These include alternative energy – ranging from solar, wind, geothermal, and tidal – additive manufacturing, and cleaner burning fuels. All of these ideas have begun to bear some serious fruit in recent years thanks to ongoing research and development. But looking to the long term, it is clear that a complete overhaul of our industrial economy is needed.

That’s where more ambitious ideas come to the fore, ideas like nanotechnology, biotechnology, and what’s known as the “Glucose Economy”. Coined by Steven Chu, a Nobel Prize-winning Chinese-American physicist who also had the honor of serving as the 12th Secretary of Energy under Barack Obama, this concept calls for the development of an economic model that would replace oil with high-glucose alternative fuels.

110302_steven_chu_ap_328Chu conceived of the idea while working as a professor of physics and molecular and cellular biology at the University of California, Berkeley. In short, the plan calls for fast-growing crops to be planted in the tropics – where sunlight is abundant – converted into glucose (of which cellulose, which makes up much of the dry weight of a plant, is a polymer). The resulting glucose and cellulose would then be shipped around much as oil is today, for eventual conversion into biofuels and bioplastics.

As expected, this would render the current system of converting oil into gasoline and plastics – a process which produces immense amounts of carbon dioxide through processing and burning – obsolete. By comparison, glucose fuels would burn clean and produce very little in the way of chemical by-products, and bioplastics would be far more resilient and eco-friendly than regular plastics, and not just because they won’t cause a terrible disposal and waste problem (see Garbage Island).

David-Benjamin-and-the-future-of-architecture-01Another benefit of the this new model is the economic development it will bring to the tropical regions of the world. As far as production is concerned, those regions that stand to benefit the most are Sub-Saharan Africa, Central and South America, and South-East Asia. These regions are already seeing significant economic growth, and a shift like this would ensure their continued growth and development (not to mention improved quality of life) for many generations  to come.

But above and beyond all that is the revolutionary potential that exists for design and manufacturing, with architects relying on specially-designed software to create multi-material objects fashioned in part from biomass. This unique combination of biological processes, computer-assisted design (CAD), and human intelligence is looking to trigger a revolution in manufacturing and construction, with everyday materials to buildings created from eco-friendly, structurally sound, biomaterials.

bio-buildingOne such architect is David Benjamin, a computational architect and principal of the New York-based practice The Living. Together with his collaborators, Benjamin is conducting experiments with plant cells, the latest of which is the production of xylem cells – long hollow tubes plants use to transport water. These are computer modeled and grown in a Cambridge University lab and studied to create materials that combine the desired properties of different types of bacteria.

In addition, they are working with sheets of calcium and cellulose, seeking to create structures that will be strong, flexible, and filigreed. And beyond The Living Thing, there are also initiatives like the Living Foundries Program, a Department of Defense initiative that is hoping to hasten the developmental process and create an emergent bio-industry that would create “on-demand” production.

1394231762-re-making-manufacturing-united-statesNot only would this shave decades off the development process, but also hundreds of millions of dollars. What’s more, Benjamin claims it could take only 8 to 10 years to see this type of biotechnology enter commercial production. Naturally, there are those who oppose the development of a “glucose economy” as advocated by Chu. Beyond the proponents of fossil fuel energy, there are also those advocate nationally self-sufficient resources bases, rather than foreign dependence.

To these critics, the aim of a future economy should be energy independence. In their view, the glucose economy is flawed in that it merely shifts energy dependence of nations like the US from the Middle East and OPEC to the tropics, which could create a whole new slew of geopolitical problems. However, one cannot deny that as alternatives go, Chu’s proposal is far preferable to the current post-peak oil model of frakking, tar sands, natural gas, and coal.

bio-building1And it also offers some new and exciting possibilities for the future, where building processes like additive manufacturing (which is already making inroads into the construction industry with anti-gravity 3D printing, and the KamerMaker House) would be supplemented by using “biohacked” bacteria to grow structures. These structures would in turn be composed of resilient materials such as cellulose and organic minerals, or possibly carbon nanotubes that are assembled by organic processes.

And the amount of money, waste, energy and lives saved would be immense, as construction is currently one of the most dangerous and inefficient industries on the planet. In terms of on the job accidents, it causes some 10,000 deaths and 400,000 injuries a year in the US alone. And in terms of resource allocation and money, construction is labor intensive, produces tons of waste, and is almost always over budget.

hacking-bacteria-bio-light-670Compared to all that, a system the utilizes environmentally-friendly molecules and materials, enhances growing operations, fostered greater development and economic cooperation, and leads to a safer, cheaper, less wasteful construction industry seems immensely preferable. And it does offer a solution of what to do about two major industries that are ailing and in desperate need of modernization.

Boy, it feels like a long time since i’ve done a conceptual post, and the topics do appear to be getting more and more serious. Can anyone recall when I used to do posts about Cool Ships and Cool Guns? Yeah, me too, vaguely. Somehow, stuff like that seems like a far cry from the Internet of Things, Interstellar Travel, O’Neill Cylinders, Space Elevators, and timelines of the future. I guess this little blog of mine has been growing up in recent years, huh?

Stay tuned for more conceptual posts, hopefully something a little lighter and fluffier next time 😉

Sources: inhabitat.com, aspenideas.org, tampabay.com

The Future is Bright: Positive Trends to Look For in 2014

Colourful 2014 in fiery sparklersWith all of the world’s current problems, poverty, underdevelopment, terrorism, civil war, and environmental degradation, it’s easy to overlook how things are getting better around the world. Not only do we no longer live in a world where superpowers are no longer aiming nuclear missiles at each other and two-thirds of the human race live beneath totalitarian regimes; in terms of health, mortality, and income, life is getting better too.

So, in honor of the New Year and all our hopes for a better world, here’s a gander at how life is improving and is likely to continue…

1. Poverty is decreasing:
The population currently whose income or consumption is below the poverty line – subsisting on less than $1.25 a day –  is steadily dropping. In fact, the overall economic growth of the past 50 years has been proportionately greater than that experienced in the previous 500. Much of this is due not only to the growth taking place in China and India, but also Brazil, Russia, and Sub-Saharan Africa. In fact, while developing nations complain about debt crises and ongoing recession, the world’s poorest areas continue to grow.

gdp-growth-20132. Health is improving:
The overall caloric consumption of people around the world is increasing, meaning that world hunger is on the wane. Infant mortality, a major issue arising from poverty, and underdevelopment, and closely related to overpopulation, is also dropping. And while rates of cancer continue to rise, the rate of cancer mortality continue to decrease. And perhaps biggest of all, the world will be entering into 2014 with several working vaccines and even cures for HIV (of which I’ve made many posts).

3. Education is on the rise:
More children worldwide (especially girls) have educational opportunities, with enrollment increasing in both primary and secondary schools. Literacy is also on the rise, with the global rate reaching as high as 84% by 2012. At its current rate of growth, global rates of literacy have more than doubled since 1970, and the connections between literacy, economic development, and life expectancy are all well established.

literacy_worldwide4. The Internet and computing are getting faster:
Ever since the internet revolution began, connection speeds and bandwidth have been increasing significantly year after year. In fact, the global average connection speed for the first quarter of 2012 hit 2.6 Mbps, which is a 25 percent year-over-year gain, and a 14 percent gain over the fourth quarter of 2011. And by the second quarter of 2013, the overall global average peak connection speed reached 18.9 Mbps, which represented a 17 percent gan over 2012.

And while computing appears to be reaching a bottleneck, the overall increase in speed has increased by a factor of 260,000 in the past forty years, and storage capacity by a factor of 10,000 in the last twenty. And in terms of breaking the current limitations imposed by chip size and materials, developments in graphene, carbon nanotubes, and biochips are promising solutions.

^5. Unintended pregnancies are down:
While it still remains high in the developing regions of the world, the global rate of unintended pregnancies has fallen dramatically in recent years. In fact, between 1995 and 2008, of 208 billion pregnancies surveyed in a total of 80 nations, 41 percent of the pregnancies were unintended. However, this represents a drop of 29 percent in the developed regions surveyed and a 20 percent drop in developing regions.

The consequences of unintended pregnancies for women and their families is well established, and any drop presents opportunities for greater health, safety, and freedom for women. What’s more, a drop in the rate of unwanted pregnancies is surefire sign of socioeconomic development and increasing opportunities for women and girls worldwide.

gfcdimage_06. Population growth is slowing:
On this blog of mine, I’m always ranting about how overpopulation is bad and going to get to get worse in the near future. But in truth, that is only part of the story. The upside is while the numbers keep going up, the rate of increase is going down. While global population is expected to rise to 9.3 billion by 2050 and 10.1 billion by 2100, this represents a serious slowing of growth.

If one were to compare these growth projections to what happened in the 20th century, where population rose from 1 billion to just over 6, they would see that the rate of growth has halved. What’s more, rates of population growth are expecting to begin falling in Asia by 2060 (one of the biggest contributors to world population in the 20th century), in Europe by 2055, and the Caribbean by 2065.

Population_curve.svgIn fact, the only region where exponential population growth is expected to happen is Africa, where the population of over 1 billion is expected to reach 4 billion by the end of the 21st century. And given the current rate of economic growth, this could represent a positive development for the continent, which could see itself becoming the next powerhouse economy by the 2050s.

7. Clean energy is getting cheaper:
While the price of fossil fuels are going up around the world, forcing companies to turn to dirty means of oil and natural gas extraction, the price of solar energy has been dropping exponentially. In fact, the per capita cost of this renewable source of energy ($ per watt) has dropped from a high of $80 in 1977 to 0.74 this past year. This represents a 108 fold decrease in the space of 36 years.

solar_array1And while solar currently comprises only a quarter of a percent of the planet’s electricity supply, its total share grew by 86% last year. In addition, wind farms already provide 2% of the world’s electricity, and their capacity is doubling every three years. At this rate of increase, solar, wind and other renewables are likely to completely offset coal, oil and gas in the near future.

Summary:
In short, things are looking up, even if they do have a long way to go. And a lot of what is expected to make the world a better place is likely to happen this year. Who knows which diseases we will find cures for? Who knows what inspirational leaders will come forward? And who knows what new and exciting inventions will be created, ones which offer creative and innovative solutions to our current problems?

Who knows? All I can say is that I am eager to find out!

Additional Reading: unstats.un.org, humanprogress.org, mdgs.un.org

Towards a Cleaner Future: Fuel Cell Breakthrough!

hydrogen-fuel-cellOne of the greatest challenges facing renewable energy is making it affordable and cost effective, to the point where it will naturally offset such sources as fossil fuels and coal. And when it comes to hydrogen fuel cells, a recent development may have accomplished just that. Quite surprising when you consider that it came from Alberta, home of the Athabasca Oil Sands and an output of roughly 4 million barrels of crude a day.

It all happened late last month, when researchers at the University of Calgary published a paper in the Journal of Science that they had come up with a much cheaper and easier way to build an electrolyzer. This is the device that uses electricity to break up water into hydrogen and oxygen, which are then used to power hydrogen fuel cells.

Picture shows the refuelling hydrogen syFor some time now, these fuel cells have been considered the most promising means of powering automobiles with a clean, renewable energy source. By recombining the two basic elements of hydrogen and oxygen, energy is generated and the only waste product is water. The only difficulty is the means of production, as electrolyzers often depend on expensive and sometimes toxic metals.

The most common of current methods involves the use of expensive rare earth metals in precise crystalline arrangements to catalyze, or speed up, the reaction. But with the new process developed by Chris Berlinguette and Simon Trudel comes into play, which involves catalyzers built out of common metals without the need for the crystal structure, the process will not only be vastly simplified but extremely cheaper.

solar_arrayBased on the estimates presented in their paper, Trudel and Berlinguette estimate that their new eletrolyzer will deliver results comparable to current techniques but at a cost of about one-one-thousandth the norm. The implications for clean, renewable energy,  such as wind or solar generators, could be enormous. Not only would it be far cheaper and more efficient, there would be far less toxic waste materials produced.

Not only that, but another major stumbling block for clean energy could be overcome. As is the case with just about any type of renewable power source – wind, solar, tidal – is that it is dependent on conditions which limit when power can be generated. But stored hydrogen energy can be used at anytime and could easily replace gas and coal, just as long as the production process is cost-effective.

hydrogencarAs Berlinguette himself pointed out, making and electrolyzer cost-effective means being able to produce power on demand and to scale:

If you think of a wind turbine producing electricity at two o’clock in the morning, there’s no one around to actually use that electricity, so it just gets dumped. If you could set that up with an electrolyzer, you could convert that electricity into hydrogen, then the next day, when there is demand, you can sell that electricity at a premium during periods of high demand.

In anticipation of the inevitable investment this will attract, Berlinguette and Trudel have already formed a company called FireWater Fuel Corp. to market their work and expect to have a commercially available electrolyzer by next year. So for those of you with money to invest and a socially-responsible, environmental outlook, get out your check books out and be prepared to invest!

Source: huffingtonpost.ca

 

The Future is Here: The (Super) Supercapacitor

supercapacitor_movieLast year, researchers at UCLA made a fantastic, albeit accidental, when a team of scientists led by chemist Richard Kaner devised an efficient method for producing high-quality sheets of graphene. This supermaterial, which won its developers the 2010 Nobel Prize in Physics, is a carbon material that is known for its incredible strength and flexibility, which is why it is already being considered for use in electronic devices, solar cells, transparent electrodes, and just about every other futuristic high-tech application.

Given the fact that the previous method of producing graphene sheets (peeling it with scotch tape) was not practical, the development of the new production process was already good news. However, something even more impressive happened when Maher El-Kady, a researcher in Kaner’s lab, wired a small square of their high quality carbon sheets to a lightbulb.

supercapacitor1After showing it to Dr. Kaner, the team quickly realized they had stumbled onto a supercapacitor material – a high-storage battery that also boasts a very fast recharge rate – that boasted a greater energy storage capacity than anything currently on the market. Naturally, their imaginations were fired, and their discovery has been spreading like wildfire through the engineering and scientific community.

The immediate benefit of batteries that use this new material are obvious. Imagine if you will having a PDA, tablet, or other mobile device that can be charged within a matter of seconds instead of hours. With batteries so quick to charge and able to store an abundant supply of volts, watts, or amperes, the entire market of consumer electronics would be revolutionized.

electric_carBut looking ahead, even greater applications become clear. Imagine electric cars that only need a few minute to recharge, thus making the gasoline engine all but obsolete. And graphene-based batteries could be making an impact when it comes to the even greater issue of energy storage with regards to solar and other renewable energy sources.

In the year since they made their discovery, the researchers report that El-Kady’s original fabrication process can be made even more efficient. The original process involved placing a solution of graphite oxide on a plastic surface and then subjecting it to lasers to oxigenate and turn the solution into graphene. A year ago, the team could produce only a few sheets at a time, but now have a scalable method which could very quickly lead to manufacturing and wide-scale technological implementation.

solar_array1As it stands, an electric car with a recharge rate of a few minutes is still several years away. But Dr. Kaner and his team expect that graphene supercapacitors batteries will be finding their way into the consumer world much sooner than anyone originally expected.  According to Kaner, his lab is already courting partners in industry, so keep your eyes pealed!

Combined with the new technologies of lithium-ion and nanofabricated batteries, we could be looking at a possible solution to the worlds energy problem right here. What’s more, it could be the solution that makes solar, wind, and other renewable sources of energy feasible, efficient, and profitable enough that they will finally supplant fossil fuels and coal as the main source of energy production worldwide.

Only time will tell… And be sure to check out the video of Dr. Kaner and El-Kady showing off the process that led to this discovery:


Source: IO9.com

Powered by the Sun: Solar-Powered Reactors

solar2Welcome back to another installment in PBTS! Today’s news item is a rather interesting one, and it comes to us from the University of Delaware where researcher Erik Koepf has come up with an interest twist on solar power. In most cases, scientists think to use cells that can absorb photons and use them to generate a flow of electrons. But in Koepf’s case, sunlight is used in a different way; namely, as a means of creating alternative fuels.

Basically, the concept for Koepft’s new solar-powered reactor revolves around the idea of getting directly to the hydrogen that is found in conventional fuels, i.e. coal and fossil fuels. While they are decent enough energy sources, they do not burn clean, due to the extensive impurities they carry and by-products they create. If it were possible to remove the essential hydrogen from them, we would have a clean burning and efficient energy supply without the hassle of pollution.

Nuclear MOX plant : recycling nuclear waste : Submerged Spent Fuel Elements with Blue GlowAnd that’s where the solar reactor comes in. As the name suggests, the reactor relies on the Sun’s energy, which it then uses to split water molecules to get at their hydrogen atoms. This is done by exposing a zinc oxide powder on a ceramic surface to massive amounts of focused sunlight. From there, a thermochemical reaction happens that splits water apart into oxygen and hydrogen.

Though it may sound complicated, the sheer beauty of this concept lies in that fact that it uses the Sun’s infinite energy to do the heavy lifting and accomplish atom smashing. No particle accelerators, no nuclear fusion or fission; and best of all, no pollution! Since the process creates no emissions or Greenhouse gases, this is perhaps one of the most environmentally friendly energy concepts to date.

But of course, the project has some additional requirement which fall under the heading, “additional parts sold separately”. For one, the reactor needs to get seriously hot – between 1750° to 1950° Celsius (3182° to 3542° Fahrenheit) – before it can get to the work of splitting water molecules. For this, a focusing mirror that is roughly 13 square meters, flawlessly flat and 98% reflective is needed.

solarpowergeNo much mirror existed when Koepf and Michael Giuliano (his research associate) got started, so they had to develop their own. In addition, that mirror needs to focus the solar energy it collects onto a tiny six centimeter circle that has to be precisely aimed. If the light is just a millimeter or two off to one side, the entire reactor could be damaged. In essence, the system is simple and ingenious, but also temperamental and very fragile.

What’s more, just how efficient it is remains to be seen. While the first tests were successful in creating small amounts of hydrogen, the  the real test will take place next month when the duo present their reactor in Zurich, Switzerland, where it will be running at full power for the very first time. Naturally, expectations are high, but it is too soon to tell if this represents the future or a failed attempt at viable alternative power.

Source: Extremetech.com