Wind Turbines on Garage

Windy City Wind Turbine Greenway Parking Garage's wind turbine system, viewed from below. via Fast Company

Chicago was nicknamed the Windy City because of its blowhard politicians, not the powerful gusts off Lake Michigan. But a new parking garage took the name to heart regardless and installed this amazing helix-shaped wind turbine system inside the building, making urban turbines not only cool, but functional.
This summer, 12 turbines started spinning at Greenway Self-Park, which bills itself, somewhat oxymoronically, as Chicago's first Earth-friendly parking garage.

Open-screen walls on the 11-story garage provide ventilation and reveal the cars inside, but also let passersby marvel at the turbines. The garage also has a cistern rain-collection system, sustainable building materials, a recycling program and an electric car charging station.Lobbies on each floor include information about how to live more sustainably, and the garage has energy-efficient lighting. The garage is pursuing pursuing LEED certification from the U.S. Green Building Council. It even has a reversible meter that can measure and return power to Chicago's grid throughout the year.
Architect Todd Halamka, director of design at the Chicago office of HOK, tells Fast Company he wanted to celebrate the building's function, not hide it.
One wonders how green a parking garage can really be, but it's not like cars are going away anytime soon, so garages might as well aim to ameliorate their impact.
And at the very least, it adds to the architecturally interesting experience of parking in downtown Chicago -- you can go underneath trains, curl up through Marina City, and now this.

Urban Wind Turbines:  via Fast Company

Sonnenschiff: Solar City Produces 4X the Energy it Consumes

by Andrew Michler

 

 

Although net-zero projects have been creating a lot of buzz lately in the field of green building, the Sonnenschiff solar city in Freiburg, Germany is very much net positive. The self-sustaining city accomplishes this feat through smart solar design and lots and lots of photovoltaic panels pointed in the right direction. It seems like a simple strategy -- but designers often incorporate solar installations as an afterthought, or worse, as a label. Designed byRolf Disc, the Sonnenschiff (Solar Ship) and Solarsiedlung (Solar Village) emphasize power production from the start by smartly incorporating a series of large rooftop solar arrays that double as sun shades. The buildings are also built to Passivhaus standards, which allows the project to produce four times the amount of energy it consumes!

  

The project started out as a vision for an entire community — the medium-density project balances size, accessibility, green space, and solar exposure. In all, 52 homes make up a neighborhood anchored to Sonnenschiff, a mixed-use residential and commercial building that emphasizes livability with a minimal footprint. Advanced technologies like phase-change materials and vacuum insulation significantly boost the thermal performance of the building’s wall system.

 

The homes are designed to the Passivhaus standard and have great access to passive solar heating and daylight. Each home features a very simple shed roof with deep overhangs that allows winter sun in while shading the building from the summer sun. The penthouses on top of the Sonnenschiff have access to rooftop gardens that make full use of the site’s solar resources. The rooftops feature rainwater recycling systems that irrigate the gardens and while supplying the toilets with greywater. The buildings also make use of wood chip boilers for heat in the winter, further decreasing their environmental footprint.
The project’s simple envelope design is brightened by a colorful and dynamic façade. Gardens and paths cross through the development as well, linking the inhabitants. Offices and stores expand the livability of the community while contributing a sense of communal purpose.

How Many Cities Have a Ban on Plastic Bags?

It's probably more than you think.

 By Rachel Cernansky

 

AP Photo/Paul Sakuma

We all know how terrible plastic bags are for the environment—they choke wildlife, they don't break down in landfills (or in oceans), they add to our demand for oil, and they aren't easy to recycle, which is the biggest reason why 90 percent of plastic bags in the U.S. are not recycled.

Yet an estimated 500 billion to 1 trillion plastic bags are used worldwide every year—380 billion of those in the U.S.—and governments have been slow-moving at best to do anything about them.
According to Salon, a study a few years ago "found that the inks and colorants used on some bags contain lead, a toxin. Every year, Americans throw away some 100 billion plastic bags after they've been used to transport a prescription home from the drugstore or a quart of milk from the grocery store. It's equivalent to dumping nearly 12 million barrels of oil."
But things are finally starting to pick up. Here's a quick look at a few spots around the world that have banned plastic bags, or at least placed a tax on their use.
U.S.
In California, the ban started in San Francisco in select stores; if pending legislation goes through, it could soon expand to all stores not only in the city, but in the entire state.
A similar ban exists in coastal North Carolina and was recently passed in Portland.
England 
In 2007, Modbury became the first town to ban the plastic bag in Britain, where 13 billion plastic bags are given away every year. If customers forget to bring their own, reports the Times Online, "a range of bags made of recycled cotton with organic and fairtrade certification will be available from £1.50 to £3.95 and cheaper paper and biodegradeable cornstarch bags will cost 5p and 10p."
Other cities have followed suit, some just a few months ago, and there are efforts to make London plastic bag-free by the time the Olympics come around in 2010. According to the Daily Mail, "Londoners use 1.6billion plastic bags a year - for an average of just 20 minutes per bag."
Mexico
Mexico City adopted a ban last summer—the second major city in the western hemisphere to do so.
India
India seems to be taking the lead in bans on plastic bags, although enforcement is sometimes questionable. Cities including Delhi, Mumbai, Karwar, Tirumala, Vasco, Rajasthan all have a ban on the bag.
Burma
A ban went into effect (with little notice) in Rangoon late last year. In neighboring China, the use of plastic bags is restricted.
Bangladesh
Plastic bags have been banned in Bangladesh since 2002, after being found to be responsible for the 1988 and 1998 floods that submerged most of the country.
Rwanda
The country, which has had a ban on plastic bags for years, has a reputation for being one of the cleanest nations not only on the continent, but in the world.
Australia 
Sydney's Oyster Bay was the first Australian suburb to ban plastic bags. Twelve towns in Australia are now said to be plastic bag-free—an effort to cut down on the estimated 6.7 billion plastic bags used in Australia every year.
Taxed, not banned
Plenty of other places have chosen not to ban plastic bags, but to discourage them through financial means. There have been taxes on plastic bags since before 2008 in Italy, Belgium, and Ireland, where plastic bag use dropped by 94 percent within weeks of the 2002 ban. In Switzerland, Germany, and Holland, the bags come with a fee.
And, in one lonely case (that I could find) of a reversal on a ban after it was implemented, Taiwan had a ban on plastic bags for three years before it lifted it in 2006.

80% Cheaper Solar Cells Switch Gold For Nickel

by Brit Liggett

One of the major drawbacks of most renewable energy sources is high cost. In order to see a huge rise in the use of renewable energy sources, prices must come down. In the world of solar there have recently been some major breakthroughs in cost advantages and efficiency increases. Scientists at the University of Toronto in Canada have come up with a way to reduce colloidal quantum dot solar cell prices by up to 80%, by swapping out costly conductive gold for cheap nickel.



Quantum dot solar cells consist of a silicon substrate that has a thin film coating of nanocrystals — or quantum dots. Gold was previously used as the conductive material in the cells and when scientists tried to switch the gold out for nickel the nickel formed new particles with the quantum dots that weren’t able to capture energy. Scientists at the University of Toronto led by Dr. Ratan Debnath found that increasing the layer of silicon substrate created a big enough barrier between the dots and the nickel that the solar cells became effective at the expected efficiency levels.
The team at University of Toronto published their findings in a paper in the July 12, 2010 issue of Applied Physics Letters and noted that with further research they believe that they will be able to increase the efficiency of their extremely inexpensive quantum dot solar panels and make them look attractive to consumers when they eventually hit the market. Unlike conventional solar panels, the quantum dot solar cells that the University of Toronto invented capture visible and infrared light. Though a mode for large scale production still hasn’t been found the impacts of these super-cheap cells could be huge.

 

 

New solar energy conversion process could revamp solar power production

New solar energy conversion process could revamp solar power production

A small PETE device made with cesium-coated gallium nitride glows while being tested inside an ultra-high vacuum chamber. The tests proved that the process simultaneously converted light and heat energy into electrical current. Credit: Photo courtesy of Nick Melosh, Stanford University

Stanford engineers have figured out how to simultaneously use the light and heat of the sun to generate electricity in a way that could make solar power production more than twice as efficient as existing methods and potentially cheap enough to compete with oil.

Unlike photovoltaic technology currently used in solar panels - which becomes less efficient as the temperature rises - the new process excels at higher temperatures.

Called 'photon enhanced thermionic emission,' or PETE, the process promises to surpass the efficiency of existing photovoltaic and thermal conversion technologies.
"This is really a conceptual breakthrough, a new energy conversion process, not just a new material or a slightly different tweak," said Nick Melosh, an assistant professor of materials science and engineering, who led the research group. "It is actually something fundamentally different about how you can harvest energy."
And the materials needed to build a device to make the process work are cheap and easily available, meaning the power that comes from it will be affordable.
Melosh is an assistant professor of materials science and engineering, and is senior author of a paper describing the tests the researchers conducted. It was published online August 1, in Nature Materials.
"Just demonstrating that the process worked was a big deal," Melosh said. "And we showed this physical mechanism does exist, it works as advertised."
Most photovoltaic cells, such as those used in rooftop solar panels, use the semiconducting material silicon to convert the energy from photons of light to electricity. But the cells can only use a portion of the light spectrum, with the rest just generating heat.
This heat from unused sunlight and inefficiencies in the cells themselves account for a loss of more than 50 percent of the initial solar energy reaching the cell.
If this wasted heat energy could somehow be harvested, solar cells could be much more efficient. The problem has been that high temperatures are necessary to power heat-based conversion systems, yet solar cell efficiency rapidly decreases at higher temperatures.
Until now, no one had come up with a way to wed thermal and solar cell conversion technologies.
Melosh's group figured out that by coating a piece of semiconducting material with a thin layer of the metal cesium, it made the material able to use both light and heat to generate electricity.
"What we've demonstrated is a new physical process that is not based on standard photovoltaic mechanisms, but can give you a photovoltaic-like response at very high temperatures," Melosh said. "In fact, it works better at higher temperatures. The higher the better."
While most silicon solar cells have been rendered inert by the time the temperature reaches 100 degrees Celsius, the PETE device doesn't hit peak efficiency until it is well over 200 degrees C.
Because PETE performs best at temperatures well in excess of what a rooftop solar panel would reach, the devices will work best in solar concentrators such as parabolic dishes, which can get as hot as 800 degrees C. Dishes are used in large solar farms similar to those proposed for the Mojave Desert in southern California and usually include a thermal conversion mechanism as part of their design, which offers another opportunity for PETE to help generate electricity, as well as minimizing costs by meshing with existing technology.
"The light would come in and hit our PETE device first, where we would take advantage of both the incident light and the heat that it produces, and then we would dump the waste heat to their existing thermal conversion systems," Melosh said. "So the PETE process has two really big benefits in energy production over normal technology."
Photovoltaic systems never get hot enough for their waste heat to be useful in thermal energy conversion, but the high temperatures at which PETE performs are perfect for generating usable high temperature waste heat. Melosh calculates the PETE process can get to 50 percent efficiency or more under solar concentration, but if combined with a thermal conversion cycle, could reach 55 or even 60 percent - almost triple the efficiency of existing systems.
The team would like to design the devices so they could be easily bolted on to existing systems, making conversion relatively inexpensive.
The researchers used a gallium nitride semiconductor in the 'proof of concept' tests. The efficiency they achieved in their testing was well below what they have calculated PETE's potential efficiency to be, which they had anticipated. But they used gallium nitride because it was the only material that had shown indications of being able to withstand the high temperature range they were interested in and still have the PETE process occur.
With the right material - most likely a semiconductor such as gallium arsenide, which is used in a host of common household electronics - the actual efficiency of the process could reach up to the 50 or 60 percent the researchers have calculated. They are already exploring other materials that might work.
Another advantage of the PETE system is that by using it in solar concentrators, the amount of semiconductor material needed for a device is quite small.
"For each device, we are figuring something like a six-inch wafer of actual material is all that is needed," Melosh said. "So the material cost in this is not really an issue for us, unlike the way it is for large solar panels of silicon."
The cost of materials has been one of the limiting factors in the development of the solar power industry, so reducing the amount of investment capital needed to build a solar farm is a big advance.
"The PETE process could really give the feasibility of solar power a big boost," Melosh said. "Even if we don't achieve perfect efficiency, let's say we give a 10 percent boost to the efficiency of solar conversion, going from 20 percent efficiency to 30 percent, that is still a 50 percent increase overall."
And that is still a big enough increase that it could make solar energy competitive with oil.
Provided by Stanford University

Stanford Unveils Solar Tech That Harnesses Light and Heat

by Cameron Scott

Photo by Nick Melosh
We currently have two types of solar energy: energy generated from light, using silicon-based photovoltaic cells, and energy generated from heat, using solar concentrators and heat-conversion systems. What if we could collect both types of energy at once? Stanford researchers recently unveiled a new solar tech that can do exactly that — their PETE devices utilize a semiconducting material coated with cesium to boost efficiency levels up to 60 percent — three times that of existing systems.

Rooftop solar panels use silicon to convert light into electricity. But their efficiency declines rapidly at higher temperatures (like those needed to power heat-conversion systems). An either/or choice presents itself — but Stanford researchers found that a cesium coating allowed semiconducting materials to convert both light and heat into energy.
They dubbed the process PETE, for photon enhanced thermionic emission. Best of all, PETE devices could be cheaply and easily incorporated into existing solar collection systems. (Because the system hits peak efficiency at over 200 degrees Celsius, it’s not a good fit for rooftop arrays.) “The light would come in and hit our PETE device first,” explained lead researcher Nick Melosh. “We would take advantage of both the incident light and the heat that it produces, and then we would dump the waste heat to existing thermal conversion systems.”
PETE devices require only a small amount of semiconducting material, making them cheap. Melosh’s team also hopes to design devices that can easily be bolted on to existing solar collection systems, so that conversion would also be low-cost.
When used with the heat-conversion process, PETE devices could reach 60 percent efficiency. But even if they boost efficiency just to 30 percent, they will bring solar power down to the price point of oil. And that’s a good thing.

 

“Wind Lens” Turbines Could Boost Energy Generation 3X

by Ariel Schwartz

Forget about traditional tri-blade wind turbines — the ultra-efficient turbine of the future might look completely different if Kyushu University professor Yuji Ohya has anything to say about it. Ohya and his team recently unveiled the Wind Lens, a honeycomb-like structure that purportedly triples the amount of wind energy that can be produced by offshore turbines.

The Wind Lens was unveiled at this month’s Yokohama Renewable Energy International Exhibition 2010. The structure works similarly to a magnifying glass that intensifies light from the sun — except in this case, the lens intensifies wind flow. Ohya’s design doesn’t have too many moving parts — just a hoop (AKA a brimmed diffuser) that “magnifies” wind power, and a turbine that is rotated by wind captured from the hoop. Each Lens, which measures 112 meters in diameter, can provide enough energy for an average household.
Ohya doesn’t know if the Lens will go into commercial production, but if nothing else, it could provide a more aesthetically appealing alternative to traditional offshore turbines.

 

Solar Power Is Cheaper Than Nuclear for the First Time

by Cameron Scott

Here’s bright spot in the news of the day: energy from new solar installations has, for the first time, become cheaper than energy from new nuclear plants, according to a new Duke University study. Thanks to cost-saving technologies and economies of scale, price can no longer be an excuse to invest in nuclear power rather than solar.

In North Carolina, nuclear energy costs 16 cents per kilowatt hour (the energy required to run 10 100-watt light bulbs for an hour), whereas solar is now going for 14 cents per kWh — a rate that continues to fall. In regions with more annual sunlight, the price gap is almost certainly even more pronounced. The data also analyzed only conventional photovoltaic power, not the concentrating technologies of troughs and reflectors, which also bring costs down.
The study was developed in response to aggressive lobbying by the nuclear industry, which has tried to position itself as the most affordable way to reduce carbon emissions. The study factors in governmental subsidies for both power sources, but found that even if all subsidies were removed, solar power would still be cheaper within a decade.

NY’s Solar Thermal Plan Will Save State $175 Million Annually

by Brit Liggett

Sixty percent of the energy used in buildings in New York State goes to heat and hot water. This power heavy fact has been the the driving force behind a newly devised solar thermal energy plan that could eventually save New York State residents $175 million a year. Given that the last nation-wide energy bill was tossed out the window, individual states are now coming under pressure to come up with their own energy saving tactics. Thankfully, even in the face of ailing government support, New York’s new solar thermal plan is a shining example of how sustainable living remains a primary cause for most individuals. The state’s forward thinking plan will call for up to 1 million new solar thermal systems placed statewide, together able to provide a total of 2,000 MWth of solar powered heat by 2020.

Solar thermal energy harnesses the power of the sun to make hot water and feed steam heating systems. Much of the heat in older buildings comes from steam heat, so officials see solar thermal as a great alternative to feeding these systems. Relative to places like Germany where the solar thermal industry is booming — they install about 200,000 solar thermal heaters per year — the US has failed to see the value of such technology, often only perceiving it as useful in low-energy contexts such as for the heating of swimming pools. However, it is estimated that solar thermal heaters have the capacity to generate 50% of the hot water needed across the US.
Understanding the gains to be had with this innovative, yet simple and easily implemented technology, New York State will kick off a program which should provide incentives, educational opportunities, permitting improvements, research and development and installer training programs to encourage the installation of solar thermal systems. The program is expected to decrease energy for heating use by 6 million US gallons of oil, 9.5 million ft³ of natural gas and displace 320 GWh of electricity production per annum. With 70% of the systems coming from residential buildings and 30% of the systems from commercial buildings, the state estimates there will be a whopping $175 million in energy savings annually.

 

Shipping Container Pavilion Springs up in San Francisco Presidio

by Moe Beitiks

Here on Inhabitat we’ve brought you shipping containers arranged as homes, schools, observatories, and stacks of glory. While you may say you’ve seen every arrangement there is to be had, we say you need to check out this container trifecta by Ogrydziak/Prillinger Architects! Besides boasting the usual specs incorporating recycled materials, this award-winning angular building comes complete with a collection of art-homes made just for the local flora and fauna. An incredible forward-thinking exhibition pavilion built for Presidio Habitats in San Francisco, this design has just received a 2010 Design Award from the American Institute of Architects, California Council (AIACC). Read ahead to learn more about this site-specific project and the local wildlife it supports.

The Presidio is an army-base turned national park located within the San Francisco city limits. The park hosts a thriving, and in some cases, endangered collection of native flora and fauna. The For-Site Foundation invited a series of artists into the park to create installations that would be able to host its native neighbors. Design challenges included creating a race challenge for the elusive Black-tailed Jackrabbit, a series of ceramic nests for the Western Screech Owl, and a few bright yellow perches for humans from which they could view the Great Blue Heron. But these were only some of the proposed projects for Presidio Habitats, and the overall exhibition pavilion displays a number of other ideas from well known eco-designers such as Amy Franceschini to Michelle Kaufmann.
The site itself is aligned along the northern San Francisco coast framing a view of the Golden Gate Bridge and catching the maximum amount of natural light. The deck, flooring and outdoor seating have been made from surplus Presidio Cypress, harvested onsite through a reforestation program. The entire structure was built off-site and put into place with a crane to reduce impact . Visitors can watch exhibition videos and learn a little bit more about their native neighbors until 2011, when the exhibition closes.

 

Artificial Photosynthesis Research Gets $122 Million DOE Funding

by Philip Proefrock

The US Department of Energy recently announced a five-year, $122 million grant to establish a new research facility in California with the goal of developing artificial photosynthesis. The Joint Center for Artificial Photosynthesis (JCAP) will seek to develop methods to create fuels directly from sunlight, water, and carbon dioxide. Key targets for this research will be catalysts and light absorbing materials needed in order to break down water and carbon dioxide in order to directly create usable fuels such as hydrogen, methanol, and methane.

 

Other technologies, such as algae biofuels retain the use of natural organisms in the process, and require refinement of the fuel, which makes them expensive. With artificial photosynthesis, the goal is to have the direct production of a usable fuel that requires little, if any, further processing.
Basic research in this field has already been carried out, but this new facility will expand on that knowledge and move toward larger scale implementations with commercial potential. The new research center will be operated by a group of research universities in California led by the California Institute of Technology along with Lawrence Berkeley National Lab, Stanford, and the Universities of California at Berkeley, Irvine, San Diego and Santa Barbara. The DOE grant will provide $22 million in the first year and $25 million for each of the remaining four years of the five-year grant to support these research programs.

 

 

Density

Do We Really All Have To Live Like New Yorkers? Does Density Matter?

by Lloyd Alter

Reading David Owen's The Green Metropolis, one would conclude that density is everything, that New York is, as he wrote in the New Yorker, "The Greenest City in America":

"Barring an almost inconceivable reduction in the earth's population, dense urban centers offer one of the few plausible remedies for some of the world's most discouraging environmental ills. To borrow a term from the jargon of computer systems, dense cities are scalable, while sprawling suburbs are not. The environmental challenge we face, at the current stage of our assault on the world's non-renewable resources, is not how to make our teeming cities more like the pristine countryside. The true challenge is how to make other settled places more like Manhattan."

Click to enlargeUrban density and transport-related energy consumption. (2009). In UNEP/GRID-Arendal Maps and Graphics Library. Retrieved 15:38, July 27, 2010 from http://maps.grida.no/go/graphic/urban-. density-and-transport-related-energy-consumption1.
But just as the Archtypes survey of Canadian cities calls this into question, so does this graph prepared by UNEP. While New York has the lowest transport-related energy consumption in the States, it is still higher than Toronto, the only Canadian city listed, every major city in Australia, and just about every city in Europe. Hong Kong is the exception that proves the rule; incredibly dense and just as efficient. At the other end of the scale is Houston, the highest energy consumer per capita on the chart. But as one wag said, "In Houston, a person walking is someone on his way to his car."
In the end, a lot of smaller, medium density cities in Australia and Europe do a lot better than New York. Density is clearly not the only factor in energy consumption per capita.

Gadling.com
A quick look at this illustration comparing gas prices shows a much closer correlation of energy consumption per capita than does a density to energy consumption comparison. Why is Toronto more efficient than New York? I live there, and it ain't Copenhagen. The only possible reason is that gas is significantly more expensive. Of course Hong Kong is the most expensive, but the Netherlands is close behind. And lo and behold, everyone there rides bikes. (Oslo is an aberation caused by the fact that it is such a big oil exporter, see the Economist Big Mac index to see how it is out of whack). Putting these two graphs together, one has to conclude that energy prices are a bigger determinant than density. It appears that long term, consistently expensive gas, cars and parking make alternative patterns of transportation and development viable.

Guelph, Ontario, with the highest walkscore I have found.
In my spare time I volunteer as president of a heritage preservation organization in Ontario, Canada, and tour the province lecturing about how heritage conservation districts are really energy conservation districts. Everywhere I go I use Walkscore as a proxy of energy efficiency and am constantly blown away by how walkable these towns are. They are usually built on rivers and have water, nearby farms, even their own hydro power generation. They were designed in a time when people didn't have cars, so things are built more closely together. But Manhattan, they are not.
David Owen, and after reading his book, this writer, were seduced by the bright lights of the big city. But the key drivers of energy efficiency appear to be less about density and more about walkability, with a big dose of gas prices thrown in to promote the latter. And in such communities where gas prices are the determinant, it is no surprise that new development is built at a walkable, cycleable density.
You can't have walkability at suburban densities, but you don't need to be New York or Hong Kong either. There is something in the middle, and it is in our smaller cities and towns all over North America.

Nanotechnology Makes Poop Power 20 Times More Efficient

by Cameron Scott

Engineers at Oregon State University have their minds in the gutter. They’re working on getting more energy from sewage, and they’ve made a discovery that boosts electricity production substantially. By applying a nanoparticle coating to the anodes in fuel cells that turn crap into currents, they increased production nearly 20-fold.

  

It may be strange to think of poop as the holy grail of anything, but poop power is a coveted form of renewable energy because it eliminates waste — which we don’t want — while producing electricity, which we do. In industrialized countries, poo power production could bring down the cost of wastewater treatment, while in developing nations, it may make it possible to treat wastewater for the first time by providing the electricity to do it. Indeed, sewage treatment systems of the future could be self-sufficient in their energy use.

In this particular potty-to-plug technology, bacteria from the sewage are placed in an anode chamber, where they consume nutrients and grow while, in the process, releasing electrons. The researchers put a nanoparticle coating on the graphite anodes – one bit of bad news: the coating was gold. Talk about flushing good money down the toilet! However, iron may work nearly as well, at least for certain kinds of bacteria.
Interesting note: OSU’s Hong Liu, an assistant professor of biological and ecological engineering, gained inspiration for the work when changing her young son’s diapers.

New Production Process Boosts Cheap Solar Cells’ Efficiency

by Cameron Scott

Photovoltaic solar cells are available in two types — crystalline silicon cells, which are more efficient but more expensive, and amorphous silicon cells, which are less efficient but cheaper and thinner and therefore more adaptable. New research from the Technical University of Delft, Netherlands, has found that using hydrogen in the production of amorphous silicon, or “thin film,” cells can increase their efficiency from the usual 7 percent to roughly 9 percent.

  

Researcher Gijs van Elzakker simply diluted the silane gas already used to produce the solar cells with hydrogen to achieve the results, meaning that the improvement is essentially free. Elzakker, who will receive his Ph.D. today (gefeliciteerd!), has already taken his findings to the German company Inventux Technologies, where he works.

Incredible Edible: How To Make Your Town Self-sufficient

by Christine Lepisto, Berlin 

Image: Incredible Edible Blog
While citizens of the world turn their eyes to Copenhagen, awaiting leadership with dwindling hope, one town has taken matters into the hands of the people. An idea that started around a kitchen table has grown into a reality demonstrating wisdom not seen since Gandhi. Starting from just a few herb gardens, the "Incredible Edible" project grew organically, out of the energy of local people who sought no public funds because they wanted to do it their way. Now "their way" shows the way. Prepare to be inspired.

In Todmorden in West Yorkshire, Great Britain, a grass-roots effort to put the land to work has grown into a project drawing national media attention, Incredible Edible. The brains and energy behind Incredible Edible is Pam Warhurst, who combines insight gained as a former leader of Calderdale Council with the commitment that comes from being involved in a just cause. The principle is simple: food unites us, all peoples regardless of social rank or means, can communicate in the language of food.
It is not a new idea. The local food movement is growing. Some are driven by dire predictions of global economic disarray in the wake of peak oil, climate change, terrorism, or another dreadful threat. Others want a simpler way of life, food grown for nutrients rather than products of an antibiotic- and pesticide-dependent industrial farming.
But even more people watch from the edges, not daring to step into the ring. Many people own no land on which a few vegetables could be grown. The skills of planting, tending and harvesting have atrophied. And who has the time?
Incredible Edible answers those questions, overcoming bureaucracy and uniting people with the common denominator, food. Following 17(ish) tips for getting things done in spite of red tape, Incredible Edible has spread food farming to public lands, gotten the local housing authority support, and spread the campaign to schools.

You just need land and the will to grow stuff on it.

Incredible Edible has planted two orchards and many veggie gardens. They work with authorities to use public space, like the fire stations and railway lands, for common gardens. Getting the social housing landlords involved reaches out to those who live in apartments without access to their own land.
School children in Todmorden eat locally grown meat and produce at every meal. Children learn from agricultural projects and participate in farms run by the schools. The Todmorden High School is now seeking funding for an aquaponics installation, which will grow fish and recycle the nutrient rich water for growing water-intensive plants, for scientific study of the environmentally-friendly food production options for the future.
It does not stop at growing food. Incredible Edible holds workshops, like how to kill and prep a chicken, how to forage for edible plants, and skills for canning and preserving. Blogs and a Twitter presence tell the ongoing story.
The Incredible Edible project is on track to meet their goal to make the town self-sufficient by 2018. A third more people grow their own vegetables, seventy percent buy locally grown produce at least once a week and 15 times more citizens tend their own chickens, compared with a year and a half ago.

World’s First Molten Salt Solar Plant Produces Power at Night

by Philip Proefrock

Sicily has just announced the opening of the world’s first concentrated solar power (CSP) facility that uses molten salt as a heat collection medium. Since molten salt is able to reach very high temperatures (over 1000 degrees Fahrenheit) and can hold more heat than the synthetic oil used in other CSP plants, the plant is able to continue to produce electricity even after the sun has gone down.

While photovoltaic solar panels work by directly producing electricity from sunlight, CSP plants use mirrors to concentrate sunlight and produce high temperatures in order to drive a turbine to generate electricity. CSP plants have been in existence for many years, but the Archimede plant is the first instance of a facility that uses molten salt as the collection medium.
Heat from the molten salt is used to boil water and drive the turbines, just like other fossil fuel plants. CSP plants use the same kind of steam turbines as typical fossil fueled power plants. This makes it possible to supplement existing power plants with CSP or even to retrofit plants to change over to clean energy producing technology. Some existing CSP plants have used molten salt storage in order to extend their operation, but the collectors have relied on oil as the heat collection medium. This has necessitated two heat transfer systems (one for oil-to-molten-salt, and the other for molten-salt-to-steam) which increases the complexity and decreases the efficiency of the system. The salts used in the system are also environmentally benign, unlike the synthetic oils used in other CSP systems.

Since molten salts solidify at around 425 degrees F, the system needs to maintain sufficient heat to keep from seizing up during periods of reduced sunlight. The receiver tubes in the Archimede facility are designed to maximize energy collection and minimize emissions with a vacuum casing that enables the system to work at very high temperatures required with molten salts. By using the higher temperatures of molten salts, instead of oil, which has been used in other CSP plants until this point, the plant is able to maintain capacity well after the sun sets, allowing it to continue generating power through the night.
The Archimede plant has a capacity of 5 megawatts with a field of 30,000 square meters of mirrors and more than 3 miles of heat collecting piping for the molten salt. The cost for this initial plant was around 60 million Euros.

MIT Uses Carbon Nanotubes to Boost Lithium Battery Power 10x

by Yuka Yoneda

An intrepid team of researchers at MIT have made a remarkable find in lithium battery technology – by using carbon nanotubes as one of a battery’s electrodes, they can increase the amount of power it can deliver by up to 10 times (compared to a conventional lithium-ion battery). Batteries are the driving force behind many great innovations in green tech but they are typically limited by the amount of power they can store, so this new finding stands to shape the future of sustainable technology.

To come to their conclusion, the team, led by Yang Shao-Horn and Paula Hammond, dipped a base material in solutions laced with carbon nanotubes that were treated with simple organic compounds that gave them either a positive or negative net charge. The dipping creates layers which, when alternated on a surface, bond tightly together because of the complementary charges, creating a stable and durable film.
So how is the new electrode material different from a conventional battery? Well, regular batteries like the ones typically used in portable electronics are made up of three parts: two electrodes (the anode, or negative electrode, and the cathode, or positive electrode) separated by an electrolyte. When the battery is in use, positively charged lithium ions travel across the electrolyte to the cathode, producing an electric current, and when it is recharged, an external current causes these ions to move the opposite way, embedding them in the spaces in the porous material of the anode.
In the MIT team’s battery, carbon nanotubes (lilliputian tubes of rolled-up carbon atom sheets) “self-assemble” into a tightly bound structure that is porous at the nanometer scale (billionths of a meter). The nanotubes also have many oxygen groups on their surfaces that have the ability to store many lithium ions, enabling the nanotubes to actually act as the positive electrode in lithium batteries. Hammond explains that the “electrostatic self-assembly” process is vital because carbon nanotubes have the tendency to clump together in bundles when on a surface, leaving fewer exposed surfaces to undergo reactions. However, by incorporating organic molecules on the nanotubes, they assemble in a way that “has a high degree of porosity while having a great number of nanotubes present.”
The new electrode’s energy output for a given weight was shown to be five times the amount of traditional capacitors, and the total power delivery rate was 10 times that of typical lithium-ion batteries, which the team attributes to good conduction of ions and electrons in the electrode, and efficient lithium storage on the surface of the nanotubes.

Ultra-Efficient Bladeless Wind Turbine Inspired by Nikolai Tesla

by Philip Proefrock

SolarAero recently unveiled a new bladeless wind turbine that offers several advantages over current wind turbines — it emits hardly any noise in operation, has few moving parts, and since it doesn’t use spinning blades it’s much less of a hazard to bats and birds. The whole assembly is inside an enclosed housing, with screened inlets and outlets to keep animals safely out. It also can be installed on sensitive locations such as radar installations or sites under surveillance where the rotating blades cause detrimental effects. Read on to learn what makes it work.

 

 

 

Whether they are vertical axis or horizontal axis, typical wind turbines work by catching moving air with blades, and using that force to rotate the axle, which turns a generator to produce electricity. Instead of pushing on blades, SolarAero’s turbine is based on the Tesla turbine originally developed by Nikolai Tesla. The principle of the Tesla turbine is to set up an array of closely-spaced, very thin, and extremely smooth metal disks. The viscous flow of air moving in parallel to the disks is what propels the turbine, instead of buffeting blades with moving air. This makes for a more compact mechanism with only one moving part: the turbine-driveshaft assembly.
According to the company, this turbine should cost around $1.50 per watt of rated output, and have a lifetime operating cost of about 12 cents per kilowatt-hour — comparable to, or even better than, current retail electrical rates in many parts of the country. This would make the SolarAero turbine about 2/3 the price of a comparable bladed unit, and because of the significantly lower operating costs, lifetime maintenance could be just 1/4 the cost. At this point the project is still under development, and no manufacturer has been lined up as of yet.

Turbine Light Illuminates Highways With Wind

by Ariel Schwartz

As more and more people across the world adopt cars as their primary mode of transportation, well-lit highways become increasingly important. But how can we sustainably power all those energy-sucking lights? TAK Studio addressed that question in their entry into this year’s Greener Gadgets competition to find the green technology solution of the future. Dubbed the Turbine Light, their design aims to illuminate our roadways using the power of the wind.

TAK’s wind-powered light uses the moving air from cars zipping by on the highway to generate energy that can be used to power roadside lighting. It’s a controversial idea–could wind from passing cars actually provide enough power for lighting?–but one that has the potential to save lots of cash in already wind-heavy regions. Alternatively, cities might consider using solar-powered lights instead. The idea has been proven to work many times over, including at the recent COP15 climate change conference.

Sanyo Unveils World’s Most Efficient Solar Module HIT-N230

by Yuka Yoneda

Electronics giant Sanyo recently announced the development of what they are claiming is the world’s most efficient solar module. Called the HIT-N230, the new module has an impressive energy conversion efficiency of 20.7% which is unprecedented in the market.

How did Sanyo achieve this feat? According to Akihabara News’ report, the leader in solar module manufacturing increased the number of solar cell tabs from 2 to 3 and made each tab thinner. They also applied AG coated glass, which allows “light trapping” or reduction of reflection and scattering of light.
While the N230 is getting the most attention for its high efficiency, Sanyo has another model in the N series – the N225 (225W) – and both are scheduled to be launched in Japan in Autumn 2010.

New Quantum Dot Photovoltaics Could Double Solar Cell Efficiency

by Cameron Scott

You’ve heard the statistic: enough solar power hits the Earth in an hour to meet our energy needs for an entire year. The trick is harnessing it. Today’s solar cells make use of just under a third of the energy hitting them, overheating to create “hot electrons” that escape before they can be converted into electricity. A study published in this week’s Science demonstrates a new type of solar technology could harness quantum dots to convert two-thirds of the sun’s energy into electrical power.

   

The technology utilizes semiconductor nanocrystals, or “quantum dots” — which slow the cooling of hot electrons to create time to grab them — and a titanium dioxide conductor to accomplish the task. A previous study pioneered the use of quantum dots to slow the electrons’ cooling. The recently documented breakthrough is significant for its use of an inexpensive titanium dioxide “wire.”
Besides taking the discovery from theoretical science into practical engineering, one big problem still remains: hot electrons also lose their energy as they travel along the wire.