China coal project risks environmental crisis - Features - Al Jazeera English

China coal project risks environmental crisis - Features - Al Jazeera English

But experts say China risks stumbling into an ecological disaster in its SNG push, as the environmental footprint of producing the gas makes even coal look green.
"This is a process that uses a lot of water and results in much more greenhouse gas emissions than conventional gas, shale gas or even coal," said Alvin Lin, China climate and energy policy director at the Natural Resources Defense Council in Beijing.
"The scale of planned coal-to-gas plans is worrying people - not just your traditional environmentalists but also energy experts who are looking at China's overall development pattern. Cleaner and more sustainable energy alternatives such as efficiency and renewables would seem to be a wiser choice," Lin added.
The carbon question
One of the biggest concerns is the carbon intensity of producing SNG. Chinese policymakers are promoting natural gas, as they want to see it displace oil products such as petrol in transportation and coal in electricity generation.
But a study by researchers in the US suggests SNG is unfit for both purposes. Burning synthetic gas to generate power produces 36 percent to 82 percent more greenhouse gas emissions than coal-fired plants, when the entire lifecycle of mining coal and then turning it into gas is taken into account, argue the study's authors, Chi-Jen Yang and Robert Jackson from the Nicholas School of the Environment at Duke University.
The case for using SNG as motor fuel fares little better. A separate study published in the journal Energy Policy found that lifecycle carbon emissions of cars running on synthetic gas were 150 percent to 190 percent higher than a normal petrol car, and up to 210 percent more than electric vehicles charged from coal-based power.
"At a minimum, Chinese policymakers should delay implementing their synthetic natural gas plan to avoid a potentially costly and environmentally damaging outcome," Yang said in a statement.
“"An even better decision would be to cancel the programme entirely."
That looks unlikely, given the dozens of facilities like the plant in Chifeng are planned across the country. In Inner Mongolia alone, which has 600bn tons of coal reserves, construction on three similar projects has under way since June and another five have received the green light to begin preliminary work.
As of September, the government has approved 18 large-scale coal-based SNG plants that will be capable of producing a total of 75.1bn cubic metres of gas every year, according to the World Resources Institute. None of these planned plants are located near large Chinese cities, so emissions generated from producing the gas will not hang directly over metropolises.
"Burning SNG in cities like Beijing will definitely reduce air pollution and greenhouse gas emissions. However, from a lifecycle perspective, it is a carbon intensive process and relocates the greenhouse gas emissions and pollution from the east to coal-rich provinces, said Wen Hua, a research analyst in Beijing with the World Resources Institute.
The net effect could mean accelerated climate change - a major concern following crucial talks over global warming at the United Nations climate conference in Warsaw, Poland.
Last week, China's top negotiator on climate change reiterated a pledge by the world's biggest greenhouse gas emitter to cut carbon emissions per unit of economic output by 40 to 45 percent by 2020 from levels in 2005.
China's policy of reducing carbon intensity would appear to be at odds with the huge Chinese investment in SNG - a contradiction that Wen blames on a lack of dialogue between energy policymakers and officials overseeing water resources.
Water stresses
The other problem with SNG is that converting coal to gas is water-intensive. Synthetic gas plants use extreme heat and pressure to gasify coal, which yields carbon monoxide and hydrogen. Steam and catalysts are then added to convert those gases to methane to produce a pipeline-ready substitute for gas.
Between six and ten litres of freshwater are needed to produce one cubic metre of SNG, compared with 0.1 to 0.2 litres for a cubic metre of shale gas. Given the size of the SNG bases China is planning, the water requirements will be enormous.
The World Resources Institute, for instance, calculated that the Inner Mongolia facility feeding Beijing will need to consume more than 32bn litres of freshwater when fully completed - enough to meet one million Inner Mongolians' domestic needs for a year.

Inside Story discusses air pollution in China

China's fledgling SNG industry is mostly concentrated in the coal-rich arid regions of Inner Mongolia and Xinjiang in far west China. Of the 18 projects approved by the government so far, 16 are located in these two areas. Sizable SNG production there would strain already limited water resources.
These 16 plants will consume up to 700m cubic metres of freshwater every year when running at full pelt, according to the World Resources Institute. That would be enough to fill 280,000 Olympic-size swimming pools.
"China faces challenges from both water supply and energy security. It is very important for policymakers to factor water considerations into their decision-making around energy issues. This means that energy authorities should be connecting local water authorities and experts to incorporate water considerations into their planning and policies," said Wen.
Potential solutions to the challenges presented by water scarcity have begun to emerge, however, including a coal-to-gas conversion process from a small US alternative energy start-up.
Massachusetts-based GreatPoint Energy is building a $1.25bn complex near the city of Turpan in Xinjiang that requires half the water used in typical gasification processes - a useful factor when setting up a gas plant in the desert.
"We are being recognised as having a very high efficiency, lower water consumption, low cost of production and the ability to use a wide range of coal types," said Daniel Goldman, president of GreatPoint Energy.
"This is very appealing to the Chinese regulators and both state-owned enterprises and private companies in China. It is an exciting time to be in the coal-to-SNG business."
Another advantage of GreatPoint's technology is that it captures carbon emissions, which can then be put to use.
"Sequestering the carbon dioxide in enhanced oil recovery reservoirs is our primary focus, since the opportunity is very large, the need is great… In Xinjiang, water can be saved by substituting carbon dioxide injection instead of water," said Goldman. "[There] is significant interest in this area."
Follow Colin Shek on Twitter: @ColinShek

Cheap Solar Energy | Cheap solar energy systems

Cheap Solar Energy | Cheap solar energy systems
 excellent info here on present and future solar tech, low cost systems, loads of info on one page!

methane from Arctic a thing to watch

http://www.dailykos.com/story/2013/11/24/1258141/-As-the-tipping-point-looms-we-all-have-to-act

About 6 years ago, one of the top climate scientists, Jim Hanson (who my wife indirectly worked for at the time), declared we have only 10 years left to mitigate the effects of global warming before we just have to take the full consequences of our stupidity right in the face. He got some criticism from this statement even among climate scientists because of the apparent precision of his estimate, but the gist of his warning is valid: we have a VERY limited time to act to mitigate the effects of global warming, and it is NOW, like RIGHT NOW, that we have to deal with this crisis.

Since he made his warning, the actual pace of global warming effects has actually ACCELERATED. So we might even have LESS time than Jim Hanson suggested. Was his warning excessively precise? Yeah, sure it was. We can't know precisely how much time we have left, but I don't think he was that far off and the more scientific info that comes in, the more I am convinced that our time to act is running out.

Arctic ice volume is expected, at current rate of decline, to reach zero (that means an ice free Arctic Ocean!) around 2015 (maybe 2016 if we are lucky!) according to modeling from the PIOMAS ice volume project at the University of Washington in Seattle. As that happens we WILL reach a critical tipping point in approximately the same time frame.

Now I personally don't think that all the supposed tipping points that hit the internet are valid. But there is one VERY clear, VERY frightening tipping point that WILL occur approximately in the same time frame as an ice-free Arctic Ocean, which means around 2015 or so. That is the release of methane that is frozen in the Arctic. From BBC News:

"In 2007, the water [off northern Siberia] warmed up to about 5C (41F) in summer, and this extends down to the sea bed, melting the offshore permafrost."
Among the issues this raises is whether the ice-free conditions will quicken release of methane currently trapped in the sea bed, especially in the shallow waters along the northern coast of Siberia, Canada and Alaska.

Methane is a much more potent greenhouse gas than carbon dioxide, though it does not last as long in the atmosphere...

"With 'business-as-usual' greenhouse gas emissions, we might have warming of 9-10C in the Arctic.

"That will cement in place the ice-free nature of the Arctic Ocean - it will release methane from offshore, and a lot of the methane on land as well."

This would - in turn - exacerbate warming, across the Arctic and the rest of the world.

The release of this much methane into the atmosphere is one of the MOST frightening things in our near future. MUCH more so than a nuclear Iran or the deficit or pretty much anything else we are facing. If we don't act RIGHT NOW to stop it, this critical tipping point WILL happen within the next 5-10 years. We will see a MASSIVE change in our climate if we don't work hard NOW to stop it. And the result will be devastating to each and every one of us.
Got that? We are RIGHT NOW at the tipping point and just about EVERY action YOU PERSONALLY take influences that tipping point.

If you have kids (like I do) look them in the eyes and ask yourself it you have done enough to stop this tipping point that will slam your kids or your grand kids like a sledgehammer.

Solar thermal's new dawn | Business Spectator

Solar thermal's new dawn | Business Spectator


Solar thermal's new dawn
Marie Rinkoski Spangler & Gwen Bredehoeft18 Nov, 8:39 AM1

    Climate
    Solar energy
    Smart Energy

US Energy Information Administration

Several large, new solar thermal power plants are expected to begin commercial operation by the end of 2013, more than doubling the solar thermal generating capacity in the United States. The projects use different solar thermal technologies and storage options.

Abengoa's Solana plant, which came on line in October, is a 250 megawatt parabolic trough plant in Gila Bend, Arizona with integrated thermal storage.

BrightSource's Ivanpah, expected to enter service by the end of this year, is a 391 MW power tower plant in California's Mojave Desert and does not include storage.

Graph for Solar thermal's new dawn

Source: US Energy Information Administration, Annual Electric Generator Report and Monthly Update (Forms EIA-860 and EIA-860M)

(Note: This map excludes generators for which solar thermal energy is not used as the primary energy source, such as the 75 MW Martin Solar Energy Center, which connects a parabolic trough field to an existing natural gas combined-cycle plant.)

Solana and Ivanpah are much larger than solar thermal plants that have previously entered service in the US. Over the past decade, a few smaller-scale and demonstration solar thermal projects have entered service. The only other dedicated solar thermal plants larger than 10 MW in the US are the series of Solar Energy Generating System plants built in California in the 1980s and early 1990s and the Nevada Solar One parabolic trough project completed in 2007.

US Energy Information Administration projections for total solar thermal capacity additions this year and next include six projects for a total of 1257 MW, with more expected in 2015 and 2016. However, while these solar thermal capacity additions are significant for the technology, they represent only 4 per cent of total expected capacity additions for 2013 and 2014 (see chart below). Solar thermal capacity additions also continue to be outpaced by solar photovoltaic capacity additions, even though solar PV has only meaningfully entered the utility-scale market in the past few years.

Graph for Solar thermal's new dawn

Source: US Energy Information Administration, Annual Electric Generator Report and Monthly Update (Forms EIA-860 and EIA-860M)

Ivanpah

Graph for Solar thermal's new dawn

Source: US Department of Energy, Loan Guarantee Program Office

Ivanpah, which is expected to come on line by the end of 2013, uses a series of three power towers: a field of movable mirrors (heliostats) focusing light on a 140m central tower. The light heats water in a boiler at the top of the tower, creating steam, which is used to run a conventional steam turbine like those in a typical fossil-fired power plant.

Solana

Graph for Solar thermal's new dawn

Source: Abengoa, used with permission

Solana, which began delivering electricity to the grid outside Phoenix, Arizona, uses parabolic, mirrored troughs to collect sunlight, as well as thermal storage, allowing the plant to operate up to six hours on stored energy alone. The parabolic troughs are movable, tracking the sun and focusing sunlight onto a tube running down the centre of each trough, which contains a heat transfer fluid. A heat exchanger creates steam that in turn runs a conventional steam turbine. (See additional resources on solar thermal technologies and images of Solana.)

Solana storage deployment

Graph for Solar thermal's new dawn

Source: Abengoa, used with permission

Solana stores some of the sun's energy as heat, using a molten salt as the thermal medium. The molten salt is stored in the round tanks, seen at the bottom center of this overhead image of Solana. This storage capability sets the plant apart from PV or wind technologies, which are dependent on the immediate availability of the sun or wind. With storage, Solana can operate while clouds pass overhead, providing a predictable supply of power to the grid. It can continue to produce electricity for up to six hours after the prime hours of sunlight have passed. This flexibility is particularly important as demand for electricity often peaks in the early evening. Storage technology was critically important in the development of Solana's 30-year power purchase agreement with Arizona Public Service (the largest utility in Arizona), which will buy all of Solana's output.

Both parabolic trough and power tower technologies can be integrated with varying levels of thermal storage. For example, the Crescent Dunes solar thermal power tower plant near Tonopah, Nevada that is expected to come on line by the end of the year will include 10 hours of thermal energy storage.

All five of the major solar thermal projects – including Solana and Ivanpah – that are scheduled to come on line in 2013 and 2014 were awarded loans through the US Department of Energy's Loan Guarantee Program. Solana received a federal loan guarantee for $US1.45 billion ($1.55 billion) of the approximately $US2 billion cost of the project, according to the parent company, Abengoa. BrightSource Energy reports a $1.6 billion federal loan guarantee on the approximately $2.2 billion Ivanpah project.

West facing PV is optimised for peak power demand!

Almost Everyone Is Angling Solar Panels the Wrong Way

Conventional wisdom in the northern hemisphere is to face solar panels south so they get the most light all day. Architects and panel installers implement this approach all the time, especially on homes. But a new study indicates that panels facing west may actually get more juice from the sun, and at more convenient times.

Researchers at the Pecan Street Research Institute did a study of homes with solar panels in Austin, Texas and found that when homeowners faced solar panels west they were able to generate 2% more electricity in a day. And they also generated more electricity in the afternoon, when power grids experience peak demand.

Though a 2% increase in electricity generation isn't enormous, it would certainly add up over the life of solar panels. And the rise in afternoon performance, reducing grid dependance during peak hours by 65% as opposed to 54% for south-facing panels, could have widespread efficiency implications beyond single homes.

It's only one study so nothing is definitive yet, but if nothing else the research raises a good point about testing solar panel performance in practice instead of just assuming that angling south is always the way to go. [Quartz via Digg]

Sony QX10 Hands on Review

http://www.youtube.com/v/ydFameGInpc?version=3&autohide=1&showinfo=1&attribution_tag=QMSehCmdtWBidq-OCmBkPQ&autohide=1&autoplay=1&feature=share

Massive coal mine leak damaged fisheries, habitat

Massive coal mine leak damaged fisheries, habitat
Alberta Environment Thursday acknowledged the one-billion-litre spill has affected fish habitat. Meanwhile, Fisheries and Oceans Canada biologists and conservation staff are inspecting a 25-kilometre stretch from the point of the release into Apetowun Creek to the Athabasca River, a breeding area for Alberta’s only strain of native rainbow trout.
Federal officials have met with managers at Sherritt International to discuss cleanup and mitigation efforts. A spokeswoman for Fisheries and Oceans said the investigation is expected to take several months.
“The sediment release did result in impacts to the fisheries and habitats,” Jessica Potter, a spokeswoman for Alberta Environment, said Thursday.
“Our fisheries biologists have done a preliminary inspection, but a full assessment won’t be possible until spring because winter weather is settling in. A larger assessment is needed to determine the full scope and extent of impacts.”
The sediment release affected the Apetowun/Plante Drainage and Athabasca Rivers, Potter said, adding, “These are trout-producing waterways.”
Provincial records show that bull trout, rainbow trout, brook trout and other species have been found in Apetowun Creek and other tributaries affected by the spill. The bull trout is designated as a species at risk in Canada, and in recent years biologists have sought protection from the province for the native strain of rainbow trout.
Alberta Environment officials are working with the company to determine how mine waste water full of clay, coal dust, dirt, sandstone and shale escaped from a containment pond at the Obed Mountain coal mine site on Oct. 31. Alberta Environment officials will not confirm if other contaminants were in the storage facility.
A Sheritt spokeswoman said no solvents are used in the water management process at the Obed mine. The company uses flocculents, a thickening agent, Paula Myson said.
The company is unable to provide the list of chemicals it uses as recorded on the Material Safety Data Sheet filed with Alberta Environment, she added.
Earlier this week, Alberta Environment began testing the Athabasca River to determine if heavy metals and cancer-contributing polycyclic aromatic hydrocarbons had been introduced by the leak.
The department said samples taken in the spill’s immediate wake posed no health risk, but then later warned communities downstream not to draw water from the Athabasca River. Farmers were likewise advised not to allow livestock to drink.
Late Friday, Alberta Environment spokeswoman Nikki Booth said testing continues on a daily basis, with results likely available next week.
“We are working with AHS on the water test results,” Booth, noting the department is still warning people not to use water from the river.
Two other waste water ponds on the mine site are not leaking and there is no concern about the integrity of those impoundments, she added.
The U.S.-based environment group, Waterkeepers Alliance, said the Obed leak, the equivalent of about 264 million gallons, would rank as the second-largest coal slurry spill in American history. The largest occurred in 2000, when 309 million gallons tainted a river in Kentucky, said Donna Lisenby of the Waterkeepers Alliance’s coal section in the U.S.
The Obed leak also far surpasses a 1972 slurry spill of 132 million gallons in West Virginia which is considered the second biggest in U.S. history, Lisenby added. The national U.S. database, called the Coal Impoundment Location and Information System, is run by industry partners and government agencies. Lisenby said she was unable to find a similar Canadian database, but given its size and the U.S. comparisons, the Oct. 31 spill is likely the biggest in Canadian history, she said.
A spokesman for Alberta’s Energy Regulator said the agency keeps records of Alberta spills, but not by volume. For that reason, Bob Curran said he could not identify Alberta’s largest spills.
In the U.S., companies are required to file a Material Safety Data Sheet that lists chemicals used in the mining process, Lisenby said in a telephone call from Boone, N.C.
“Each coal mine is unique” in the process it uses, she said.
“It can be as simple as using just water but in modern times more chemicals are used — coagulants, solvents that might include heavy metals,” Lisenby said. “It’s critical that those water tests are made public.
“Folks downstream need to know.”
At mid-afternoon Friday, Booth said a murky ribbon of pollution 113 km long was drifting with the current in the Athabasca River. The head of the plume was approximately 45 km north of Smith, while the tail was 15 km upstream of the Highway 33 Bridge at Fort Assiniboine.
Carl Hunt, a fisheries biologist for the province for 33 years, said Wednesday that he suspected significant damage had occurred in Apetowun Creek and other tributaries of the Athabasca. Among other things, sediment can coat the bottom and kill invertebrates upon which trout and other species feed.
“This sediment spill will hopefully raise public awareness,” said Hunt, who is now retired.
A biologist with Trout Unlimited Canada, Brian Meagher petitioned then environment minister Frank Oberle in 2010 for protection for Alberta’s lone native strain of rainbow trout. Nothing ever became of the request.
“If a spawning stream was affected by this spill it could definitely be a major issue,” Meagher said.
mklinkenberg@edmontonjournal.com

Smart Wheel By FlyKly Could Change Everything About Commuting

Smart Wheel By FlyKly Could Change Everything About Commuting

The phrase “This changes everything” gets thrown around a lot, but in the sustainable commuting sphere, an invention out of New York by a group of bike enthusiasts just might actually change everything.
The Smart Wheel by FlyKly Bikes is a motorized bike wheel that can fit on almost any bike, instantly turning a regular bike into an electric one, opening up the options of who can bike commute, where, how far and in what terrain.
Bike commuting in urban areas has the potential to combat an enormous number of problems: traffic congestion, air pollution, gas consumption, and commuting affordability. But would-be bikers are often limited by various constraints, including weather, physical condition, cost and time.
In most of the American cities with the worst traffic, such as Los Angeles, Houston, Honolulu or the Bay Area, commuters are constrained by hills, heat and sprawling distances.
Electric bikes, which have motors attached to them, were meant to solve some of those problems, but often end up being prohibitively expensive. Some e-bike lines’ most basic models start above $1200, and can easily surpass $2000.
So FlyKly’s Niko Klansek decided to “turn an ordinary bike into a smart bike.”
“We want to make cities more livable, and make them more people -- not car -- friendly,” says Klansek.
Enter the Smart Wheel, a wheel that can replace almost any bike’s back tire. The wheel hub has a self-contained, battery-powered motor that can propel a bike at speeds as high as 20 miles per hour for as far as 30 miles on one charge. The wheel recharges itself when coasting downhill.

FlyKly hopes the Smart Wheel will encourage people to use their bikes at times they previously thought they could not. “Without losing your breath or breaking a sweat,” they promise, “there’s no need to worry about what to wear to that business meeting or 8 o’clock date.”
The device earns its “Smart” moniker by being operated completely through one’s smartphone, which stays put on a handlebar mount (that also serves as a bike light and a phone charger) and connects to the wheel through Bluetooth. The FlyKly app monitors speed, distance, time traveled, location and route.

Before setting out on a ride, the cyclist sets the maximum speed at which they want to travel through the app. The wheel senses when the rider starts pedaling and adjusts speed accordingly. FlyKly says the app is also able to learn the rider’s cycling habits and routines and suggest “faster, safer, and more fun routes to take.”
The wheel can be locked via the app, and if the bike starts to move when the phone is not nearby, the app sends a message alerting its owner to a possible theft.

FlyKly hopes users will also use the app to track their preferred routes and share them with city officials who may be planning bike lanes and trying to improve bike-friendliness in urban areas. The company’s goal with the Smart Wheel is to “reshape the cities ... in a way that again people, not cars, come first.”

Given the incredible early show of support, achieving their goal seems quite plausible. The company launched a kickstarter this October with a goal of raising $100,000. They have already raised over $275,000 and counting.
Though FlyKly has not yet decided what the final price for the Smart Wheel will be, they assure it will be far less than an electric bicycle. Since the wheel is removable, the invention is also more versatile than an e-bike. After all, sometimes you want to be the one powering your bike with your own pedaling. But when you don’t, or can’t, Smart Wheel will be there.

'Smart' streetlamps light up when you're near - CNN.com

'Smart' streetlamps light up when you're near - CNN.com
Imagine if a streetlamp knew you were coming. It could announce your arrival from a distance. If you were on a date, it could help set the mood. It could ring in the new year with dazzling effects, change color at will, even announce days in advance when its bulb was set to blow.

In fact, there is nothing future-tense about this fantastical vision; in a handful of municipalities in Europe, streetlights have become downright chatty.

The system is called Tvilight. It was invented by Dutch designer Chintan Shah while a student at Delft University of Technology in the Netherlands. When flying overseas, he noticed streetlamps lighting streets that, in the middle of the night, were empty and desolate.

"I started researching," he says. "I wondered, why are they burning? How much does it cost? Is this a problem? I discovered some amazing numbers."

Shah found that Europe pays over €10 billion ($13 billion) a year powering streetlights, which accounts for more than 40% of government energy bills.

This translates into 40 million tons of CO2 emissions annually -- enough to power 20 million cars. His solution was to create an intelligent, "on-demand" lighting system using wireless sensors. Streetlights only light up in the presence of a person, bicycle or car, and remain dim the rest of the time.

Shah has also developed the technology to distinguish between people and smaller animals, like cats and mice, so it would avoid lighting up unnecessarily.

"I thought, why should each citizen pay for street lights that aren't being used? We now have a solution for that."

Spurred on by his professors, Shah entered the concept in a campus competition and won. Delft handed over their facilities and gave him the financial backing to create a demonstration on campus. Since then, Tvilight has been implemented in four municipalities in Holland and one in Ireland, with many more to come.

"We have enquiries from Israel, Turkey, the United States, Australia, India and Japan. The problem is not a lack of enquiries, it's the team's capacity to deliver the solution worldwide," he says.

Shaw reckons the system will slash energy costs and CO2 emissions by 80%, and maintenance by another 50%, thanks to the integrated wireless sensor that allows lamps to alert a central control center when it's time to be serviced.

Tvilight's primary purpose is to conserve energy. But when CNN invited Dutch artist Daan Roosegaarde to offer advice as a mentor for Shah, he pointed to the technology's more artistic potential.

"How can we use the technology to make environments more human? More sustainable? More natural?" asks Roosegaarde. "We want to make it like it's your friend, or it's an animal, or it does things you don't know about. It's not just a machine with a feedback loop, but something that has its own intelligence and is willing to negotiate, to hack you in the same way you hack it."

So, for example, an ambulance or fire truck could communicate with the lamps to make them flicker red before they drive through

Highly Transparent, Efficient OPV Incorporates Photonic Crystal

Solar Novus - Applications - Highly Transparent, Efficient OPV Incorporates Photonic Crystal

Researchers at The Institute of Photonic Sciences (ICFO), Barcelona, Spain, have created a highly transparent, highly efficient organic solar cell with promising potential for integration into windows and displays. Reaching 5.6% efficiency, the cell’s performance approaches that of its opaque counterparts.
The ICFO cell’s active layer is a blend of a polymer (PTB7) and a derivative of fullerene (PC71BM) and has a transparency close to 50%. By comparison, a typical transparency value for sunglasses is about 15%. A standard OPV would not be transparent to visible light, because the device incorporates a metal electrode that is completely opaque. In case of the ICFO cell, the electrode is made of silver. The group thinned that material to just 10 nm. “This gives the device a homogenous semi-transparency that ranges from 30 to 40%,” says Jordi Martorell, UPC Professor at ICFO and leader of the study.
Thinning the electrode would normally compromise the device’s ability to absorb the near-infrared and near-ultraviolet photons not visible to the eye, which would decrease the overall conversion efficiency. The ICFO group solved this dilemma by incorporating a photonic crystal that increases the amount of infrared and ultraviolet light absorbed by the cell. “The photonic crystal we designed sends these photons back to the active material but is transparent to visible photons,” Martorell explains, adding that the cell’s photon-to-charge conversion efficiency is close to 80% of that of the original opaque device. “To the best of our knowledge, such a level of efficiency when comparing 30% semitransparent to opaque devices has never been achieved before.”
“What makes it even more interesting is that one may tune the photonic crystal to optimise sun photon absorption for vertical PV installations, which is the natural type of installation in big cities, since the largest amount of transparent surface is vertical instead of horizontal,” Martorell elaborates. “No other PV technology, including other types of OPVs, can achieve the same goal so effectively.” What is more, to make the design even more appealing for such BIPV applications, the colour of the cells can be tuned by simply changing the layer configuration of the photonic crystal.
The expert agrees that integrated transparent solar cells, such as the one his group debuted, could soon revolutionise the way people use solar energy. “In my opinion semitransparent OPVs will represent a major step in the integration of energy production with energy consumption,” Martorell says. “With the technology developed at ICFO, which is patent-pending, we take such integration one step further.” And with an overall power conversion efficiency of 5.6%, he believes his device “is already acceptable for practical applications.”
Asked when ICFO’s device could become commercially viable, though, Martorell says a definite answer is “difficult,” citing several “strictly technical” challenges, such as scalability or stability. While his group knows how to address these challenges, and will focus on that next, there are “many other issues” out of the researchers’ control: “… for instance, capital investment, a favourable legislation, production costs compared to other type of windows, etc., which have little to do with the technology itself but that may play a larger role in terms of when we will see commercial PV windows.”
As it stands, this type of integrated organic solar cell would mostly find application in BIPV, Martorell says. “However, we intend to increase the transparency up to levels that make the technology also applicable for the industry of tablets, smart phones, and displays, which require levels of transparency close to 90%.” To increase the level of transparency, the ICFO group will focus on new materials and alternative device configurations going forward.
The results of this study are detailed in the paper “Transparent polymer solar cells employing a layered light-trapping architecture,” published in Nature Photonics.

Overview | TMP36 Temperature Sensor | Adafruit Learning System

Overview | TMP36 Temperature Sensor | Adafruit Learning System:

'via Blog this'

The combination of connecting a Raspberry Pi to COSM makes creating a internet of things much easier than it has been in the past. The Pi with it's easy access to ethernet / WiFi and COSM's drop dead simple usability will graph all sensor data you send to it. 

This tutorial explains how to connect a analog temperature sensor to the Pi and use a small python script to upload that data for storage and graphing on COSM.

To follow this tutorial you will need

• MCP3008 DIP-package ADC converter chip
• Analog Temperature Sensor TMP-36
• Adafruit Pi Cobbler - follow the tutorial to assemble it
• Half or Full-size breadboard
• Breadboarding wires
• Raspberry Pi with a internet connection

Hey, that photo up there has the GPIO cable in backwards - so when you wire it up don't follow that pic!

Overview | TMP36 Temperature Sensor | Adafruit Learning System

Overview | TMP36 Temperature Sensor | Adafruit Learning System

These sensors use a solid-state technique to determine the temperature. That is to say, they don't use mercury (like old thermometers), bimetalic strips (like in some home thermometers or stoves), nor do they use thermistors (temperature sensitive resistors). Instead, they use the fact as temperature increases, the voltage across a diode increases at a known rate. (Technically, this is actually the voltage drop between the base and emitter - the Vbe - of a transistor.) By precisely amplifying the voltage change, it is easy to generate an analog signal that is directly proportional to temperature. There have been some improvements on the technique but, essentially that is how temperature is measured.

Because these sensors have no moving parts, they are precise, never wear out, don't need calibration, work under many environmental conditions, and are consistant between sensors and readings. Moreover they are very inexpensive and quite easy to use.

Some Basic Stats

These stats are for the temperature sensor in the Adafruit shop, the Analog Devices TMP36 (-40 to 150C). Its very similar to the LM35/TMP35 (Celsius output) and LM34/TMP34 (Farenheit output). The reason we went with the '36 instead of the '35 or '34 is that this sensor has a very wide range and doesn't require a negative voltage to read sub-zero temperatures. Otherwise, the functionality is basically the same.

• Size: TO-92 package (about 0.2" x 0.2" x 0.2") with three leads
• Price: $2.00 at the Adafruit shop
• Temperature range: -40°C to 150°C / -40°F to 302°F
• Output range: 0.1V (-40°C) to 2.0V (150°C) but accuracy decreases after 125°C
• Power supply: 2.7V to 5.5V only, 0.05 mA current draw
• Datasheet

How to Measure Temperature

Using the TMP36 is easy, simply connect the left pin to power (2.7-5.5V) and the right pin to ground. Then the middle pin will have an analog voltage that is directly proportional (linear) to the temperature. The analog voltage is independant of the power supply.