But that’s not all that WISE caught in this busy image — two natural satellites orbiting above WISE streak through the image, appearing as faint green trails. This Tadpole region is chock full of stars as young as only a million years old — infants in stellar terms — and masses over 10 times that of our sun. It is called the Tadpole nebula because the masses of hot, young stars are blasting out ultraviolet radiation that has etched the gas into two tadpole-shaped pillars, called Sim 129 and Sim 130. These “tadpoles” appear as the yellow squiggles near the center of the frame. The knotted regions at their heads are likely to contain new young stars. WISE’s infrared vision is helping to ferret out hidden stars such as these.

The 1719 Jens asteroid, discovered in 1950, orbits in the main asteroid belt between Mars and Jupiter. The space rock, which has a diameter of 19 kilometers (12 miles), rotates every 5.9 hours and orbits the sun every 4.3 years.

Twenty-five frames of the region, taken at all four of the wavelengths detected by WISE, were combined into this one image. The space telescope caught 1719 Jens in 11 successive frames. Infrared light of 3.4 microns is color-coded blue: 4.6-micron light is cyan; 12-micron-light is green; and 22-micron light is red.

WISE is an all-sky survey, snapping pictures of the whole sky, including everything from asteroids to stars to powerful, distant galaxies.

Image Credit: NASA/JPL-Caltech/UCLA

Astroid Traveling Through Space

The full moon is seen as it rises near the Lincoln Memorial

The full moon is called a super perigee moon since it is at its closest to Earth in 2011. The last full moon so big and close to Earth occurred in March 1993.

WASHINGTON, DC — NASA has signed a $753 million modification to the current International Space Station contract with the Russian Federal Space Agency for crew transportation, rescue and related services from 2014 through June 2016. The firm-fixed price modification covers comprehensive Soyuz support, including all necessary training and preparation for launch, flight operations, landing and crew rescue of long-duration missions for 12 individual space station crew members.

NASA has efforts underway to develop an American-made commercial capability for crew transportation and rescue services to the station following this year’s retirement of the space shuttle fleet. Agency Administrator Charles Bolden cited this week’s Soyuz contract extension as a reminder of how critically important those efforts are.

“The president’s 2012 budget request boosts funding for our partnership with the commercial space industry and prioritizes our efforts to ensure that American astronauts and the cargo they need are transported by American companies rather than continuing to outsource this work to foreign governments,” Bolden said. “This new approach in getting our crews and cargo into orbit will create good jobs and expand opportunities for our American economy. If we are to win the future and out build our competitors, it’s essential that we make this program a success.”

NASA made Commercial Crew Development awards in 2010 to stimulate efforts within the private sector, encouraging them to develop and demonstrate human spaceflight capabilities. The agency anticipates these systems will be available by the middle of the decade.

These services will provide our primary transportation to and from the International Space Station for U.S., Canadian, European and Japanese astronauts. To ensure a smooth transition as this new capability is developed, Soyuz support will continue as a backup capability for about a year after commercial services begin.

With this contract modification, station crew members may launch on Soyuz vehicles during a 24-month period. The contract will provide for the launch of six people in calendar year 2014 and six more in 2015, as well as their return to Earth in the spring of 2016 after a six-month stay aboard the station. The extended contract ends June 30, 2016.

Under the contract modification, the Soyuz flights will carry limited cargo associated with crew transportation to and from the station, and assist with the disposal of trash. The cargo provided per Soyuz seat is approximately 110 pounds (50 kilograms) launched to the station, approximately 37 pounds (17 kilograms) returned to Earth and trash disposal of approximately 66 pounds (30 kilograms).

For more information about the International Space Station, visit:

http://www.nasa.gov/station

E15 (a blend of gasoline and ethanol)

In response to a request by Growth Energy under section 211(f)(4) of the Clean Air Act, the Environmental Protection Agency (EPA) has partially granted a waiver to allow fuel and fuel additive manufacturers to introduce into commerce gasoline that contains greater than 10 volume percent (vol%) ethanol and up to 15 vol% ethanol (E15) for use in model year (MY) 2001 and newer light-duty motor vehicles, subject to several conditions. On October 13, 2010, EPA granted a partial waiver for E15 for use in MY2007 and newer light-duty vehicles (i.e., cars, light-duty trucks and medium-duty passenger vehicles). On January 21, 2011, EPA granted a partial waiver for E15 for use in MY2001-2006 light-duty motor vehicles. These decisions were based on test results provided by the U.S. Department of Energy (DOE) and other information regarding the potential effect of E15 on vehicle emissions. Taken together, the two actions allow, but do not require, E15 to be introduced into commerce for use in MY2001 and newer light-duty motor vehicles if conditions for mitigating misfueling and ensuring fuel quality are met. EPA is in the process of completing work on regulations that would provide a more practical means of meeting the conditions.

Prior to the distribution of E15, fuel and fuel additive manufacturers are required to register the fuel with EPA. For more information on fuel registration visit the Registration and Health Effect Testing page. There are also a number of other actions including changes to various state and local laws that may also affect the distribution of E15.

What is E15?

Ethanol is an alcohol that can be mixed with gasoline to result in a cleaner-burning fuel. The most common blend of gasoline and ethanol is E10, or 10 percent of ethanol to 90 percent of gasoline. E10 was granted a waiver under Clean Air Act section 211(f)(4) by operation of law over 30 years ago. E15 is gasoline containing 15 vol% ethanol.

The primary source of ethanol is corn, but other grains or biomass sources may be used.
What is the E15 waiver?

In order to protect the emission control systems of vehicles and engines, the Clean Air Act prohibits the introduction of fuels or fuel additives that are not substantially similar to the fuels or fuel additives used in certifying vehicles and engines to emission standards. However, the Act authorizes EPA to grant a waiver of this prohibition for a fuel or fuel additive if it can be demonstrated that vehicles and engines using the otherwise prohibited fuel or fuel additive will continue to meet emission standards over their “full useful life” (100,000 or 120,000 miles, depending on the vehicle type and model year).

In March 2009, Growth Energy (a coalition of U.S. ethanol supporters) and 54 ethanol manufacturers applied for a waiver to increase the allowable amount of ethanol in gasoline from E10 to E15. The waiver application included data on the impact of E15 on vehicle emissions, fuel system materials, and driveability. Additional data were developed by DOE, which in 2008 began testing for potential impacts of various ethanol-gasoline blends on emissions of MY2007 and newer light-duty motor vehicles. This testing followed enactment of the Energy Independence and Security Act of 2007, which calls for significantly increasing the amount of biofuels, such as ethanol, to be used in transportation fuel. EPA received over 78,000 public comments about Growth Energy’s application.

Initially, EPA partially granted Growth Energy’s waiver request application. Based in large part on DOE test data, the Agency approved the waiver for and allowed the introduction into commerce of E15 for use in MY2007 and newer light-duty motor vehicles, subject to certain conditions. EPA did not approve the waiver for E15 use in MY2000 and older light-duty motor vehicles, heavy-duty gasoline engines and vehicles (e.g., delivery trucks), highway and off-highway motorcycles, and nonroad engines, vehicles, and equipment (e.g., boats, snowmobiles, and lawnmowers) due to insufficient test data or other information to support a waiver for these vehicles and engines. At the time of the announcement in October, EPA deferred action on E15 for use in MY2001-2006 light-duty motor vehicles until DOE test data for those model years became available.

On January 21, 2011, after DOE test data were made available to the public (see EPA Docket #EPA-HQ-OAR-2009-0211 at www.regulations.gov), EPA took further action on Growth Energy’s waiver request application to approve the introduction into commerce of E15 for use in MY 2001-2006 and newer light-duty motor vehicles, subject to the same conditions that apply to the partial waiver decision for later model year vehicles. Taken together, the two waiver decisions allow the introduction into commerce of E15 for use in MY2001 and newer light-duty motor vehicles if the waiver conditions are met.
What Vehicles May Use E15?

* Flexible-fuel vehicles (FFVs).
* MY2001 and newer cars.
* MY2001 and newer light-duty trucks.
* MY2001 and newer medium-duty passenger vehicles. (SUVs).

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What Vehicles and Engines May Not Use E15?

* All motorcycles.
* All vehicles with heavy-duty engines, such as school buses, transit buses, and delivery trucks.
* All off-road vehicles, such as boats and snowmobiles.
* All engines in off-road equipment, such as lawnmowers and chain saws.
* All MY2000 and older cars, light-duty trucks, and medium-duty passenger vehicles (SUVs).

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What Conditions are Part of the Waiver Decision?

EPA placed two types of conditions on the waiver for E15: those for mitigating the potential for misfueling of E15 into vehicles, engines and equipment for which E15 is not approved, and those addressing fuel and ethanol quality. All conditions must be met prior to the introduction of E15 into commerce.

Fuel quality conditions:

* Ethanol used for E15 must meet ASTM International D4806-10.
* The Reid Vapor Pressure for E15 is limited to 9.0 psi during the summertime.

Misfueling mitigation conditions:

* Labels must be placed on E15 retail dispensers indicating that E15 use is only for MY2001 and newer motor vehicles.
* Product Transfer Documents (PTDs) must accompany all transfers of fuels for E15 use.
* Parties involved in the manufacture of E15 must participate in a survey of compliance at fuel retail dispensing facilities to ensure proper labeling of dispensers.
* Parties must submit a plan addressing conditions to EPA for approval.

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What is EPA doing to Address Potential Misfueling?

EPA is in the process of establishing a regulatory program to help mitigate potential misfueling of vehicles, engines, and equipment for which E15 is not approved. Concurrently with the October 13, 2010 partial waiver decision, the Agency proposed a rule that would require all E15 fuel dispensers to have a label if a retail station chooses to sell E15, and sought comment on separate labeling requirements for fuel blender pumps and fuel pumps that dispense E85. Similar to the prohibition in Clean Air Act section 211(f)(1), the rule would prohibit the use of gasoline containing greater than 10 vol% ethanol in vehicles and engines not covered by the partial waiver for E15. In addition, the rule would require PTDs specifying ethanol content and Reid Vapor Pressure (RVP) to accompany the transfer of gasoline blended with ethanol and a national survey of retail stations to ensure compliance with these requirements. The rule would also modify the Reformulated Gasoline (RFG) program by updating the Complex Model to allow fuel manufacturers to certify batches of gasoline containing up to E15. The measures were designed to help promote the successful introduction of E15 into commerce.

EPA held a public hearing on the proposed rule in November and provided a 60-day public comment period that ended on January 3, 2011.

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Notices and Updates
NOTE: You will need Adobe Acrobat Reader, available as a free download, to view some of the files on this page. See EPA’s PDF page to learn more about PDF, and for a link to the free Acrobat Reader.

Under the authority of Clean Air Act section 211(f)(4), EPA may consider the March 2009 application from Growth Energy for a waiver for a gasoline-ethanol blend with up to 15 vol% ethanol (E15) to be used in non-flexible-fueled vehicles.

EPA reviewed Growth Energy’s application along with available test data, other information and public comments. On October 13, 2010, EPA determined that, subject to compliance with the conditions listed in the waiver decision, a gasoline produced with greater than 10 volume percent (vol%) ethanol and up to 15 vol% ethanol will not cause or contribute to a failure of MY 2007 and newer cars, light-duty trucks and medium-duty passenger motor vehicles to achieve compliance with applicable emission standards over the vehicles’ full useful life. Therefore, EPA partially and conditionally granted Growth Energy’s waiver request for a gasoline-ethanol blend with up to 15 vol% ethanol. On January 21, 2011, EPA took further action on Growth Energy’s waiver request and granted a partial waiver for E15 use in MY 2001-2006 cars, light duty trucks and medium-duty passenger vehicles, subject to the same conditions that apply to the partial waiver for newer light-duty motor vehicles.

* Partial waiver for use of E15 in MY2001-2006 light-duty motor vehicles | PDF Version (22 pp; 2.7MB; January 26, 2011)
* Fact Sheet: EPA Announces E15 Partial Waiver Decision | PDF Version (3 pp; 510K; EPA-420-F-11-003; January 21, 2011)
* Partial waiver for use of E15 in MY2007 and newer light-duty motor vehicles | PDF Version (58 pp, 4.57M, published November 4, 2010)
* Status Update (July 2010)
* Status Update (PDF) (2 pp, 493K, November 30, 2009)
* Extension of Comment Period: Notice | PDF Version (2 pp, 75K, published May 20, 2009)
* Notice of Receipt of Waiver Application | PDF Version (3 pp, 77K, published April 21, 2009)

For further information or assistance, please contact Robert Anderson (anderson.robert@epa.gov) or at 202-343-9718.

North American Archaeological Dig

The National Science Foundation scientists and Alaska Natives collaborate on find of cremated child.

Newly excavated remains found at the Xaasaa Na’ archaeological site near the Tanana River in central Alaska may belong to one of the earliest inhabitants of North America.

The remains of an individual, estimated to be about three-years old at the time of death, may provide rare insights into the burial practices of Ice Age peoples, while shedding new light on their daily lives, according to a paper published Feb. 25 in the journal Science.

Researchers, who named the child Xaasaa Cheege Ts’eniin (pronounced hausau chag ts’eneen), which translates to “Upward Sun River Mouth Child,” based on a local native place name, said the remains would be the oldest found in Northern North America, as well as the second youngest Ice Age child on the continent.

The find also is notable because archaeologists and Alaska Natives are working hand-in-hand to insure the excavation and subsequent examination of the child’s remains.

Ben Potter, an archaeologist at the University of Alaska Fairbanks, and his colleagues describe in the paper finding the skeletal remains in an ancient fire pit within an equally ancient dwelling near the Tanana River.

Radiocarbon dating of wood at the site indicates the cremation of the child may have taken place roughly 11,500 years ago, when the Bering Land Bridge may still have connected Alaska with Asia.

Initial observations of the teeth indicate the child is biologically affiliated with Native Americans and with Northeast Asians.

“This site reflects many different behaviors never before seen in this part of the world during the last Ice Age, and the preservation and lack of disturbance allows us to explore the life ways of these ancient peoples in new ways,” Potter says.

The researchers note both the burial and the house itself are the earliest of their kind known in the North American near-Arctic. They add that discovery of burial sites of this age in North America is very rare; the buried remains of children even more so.

“The discovery of the remains was unexpected,” Potter added.

In fact, it was an older occupation at the site–about 13,200 years ago–that first attracted the researchers to the site. Only while investigating this early occupation did the evidence of the burial come to light.

The initial excavation of the site was supported by the National Science Foundation’s Office of Polar Programs with funds awarded under the American Recovery and Reinvestment Act.

OPP’s Division of Arctic Sciences supports disciplinary, multidisciplinary, and broad, interdisciplinary investigations directed toward both the Arctic as a region of special scientific interest and a region important to global systems.

In the paper, the researchers note that the pit contained not only the child’s remains–the researchers estimate less than 20 percent of the skeleton survived the cremation–but also remains of small mammals, birds and fish as well as plant remains. Because the human remains were in the uppermost part of the pit, above the animal remains, the researchers suspect the pit was not originally designed as a grave, but evidence suggests the occupants abandoned the house after the cremation-burial.

Both researchers and tribal leaders agreed that the process of working together on this new find has fostered mutual respect and cooperation between them.

“This exciting, groundbreaking and multi-faceted research is in the best traditions of the research that NSF supports in the Arctic,” said Anna Kerttula de Echave, program officer in the NSF Office of Polar Programs who oversees this award. “Equally significant is that the approach taken by the researchers reflects the importance, in modern Arctic science, of collaborating with Native people as full partners in discovery.”

Potter and his colleagues’ excavation and analysis were sanctioned by the local federally recognized Tribe, Healy Lake Traditional Council and its affiliated regional consortium, Tanana Chiefs Conference (TCC). Through consultation, initiated at the time of the discovery, Healy Lake and TCC support the scientific examination of both the site and the remains themselves.

“I would like to learn everything we can about this individual,” said First Chief Joann Polston, of Healy Lake Traditional Council.

TCC President Jerry Isaac added that “This find is especially important to us since it is in our area, but the discovery is so rare that it is of interest for all humanity.”

Although burned, some of the child’s remains may retain DNA. Isaac intends to have his own DNA compared to the find. Polston would like to expand the opportunity to any Alaska Native in the region.

Based on the stratigraphy–or examination of layers of materials in the fire pit–and other evidence, the researchers describe a possible sequence for how the remains came to be interred at the site.

They hypothesize a small group of people, which included adult females and young children, were foraging in the area in the vicinity of this residential camp, fishing and hunting birds and small mammals.

A pit was dug within a house, used for cooking and/or a means of disposing food debris for weeks or months preceding the death of the child.

The child died and was cremated in the pit.

The pit was likely filled with surrounding soil soon after the body was burned. The house was fairly soon abandoned, they concluded, due to the lack of artifacts found above this fill.

Potter noted the find is significant also because it crosses a number of disciplinary boundaries; the artifacts, features, stratigraphy, preservation, and the human remains. These finds allow for the integration and synthesis of stone tool technology, cultural affiliation, subsistence economy, seasonal use of the landscape, paleoenvironments and climate change at the end of the last Ice Age northern North America.

-NSF-

Media Contacts
Deborah Wing, NSF (703) 292-5344 dwing@nsf.gov
Marmian Grimes, University of Alaska Fairbanks (907) 474-7902 marmian.grimes@alaska.edu

Program Contacts
Anna M. Kertulla, NSF (703)292-7432 akertull@nsf.gov

Principal Investigators
Ben A. Potter, Unversity of Alaska Fairbanks (907) 474-7567 bapotter@alaska.edu

The National Science Foundation (NSF) is an independent federal agency that supports fundamental research and education across all fields of science and engineering. In fiscal year (FY) 2010, its budget is about $6.9 billion. NSF funds reach all 50 states through grants to nearly 2,000 universities and institutions. Each year, NSF receives over 45,000 competitive requests for funding, and makes over 11,500 new funding awards. NSF also awards over $400 million in professional and service contracts yearly.

As plants and animals near the surface of the ocean die and decay, they fall toward the sea floor, just like leaves and decaying material fall onto a forest floor. In addition to dead animals and plants, marine snow also includes fecal matter, sand, soot, and other inorganic dust.

The decaying material is referred to as “marine snow” because it looks a little bit like white fluffy bits. The “snowflakes” grow as they fall, some reaching several centimeters in diameter. Some flakes fall for weeks before finally reaching the ocean floor.

This continuous rain of marine snow provides food for many deep-sea creatures. Many animals in the dark parts of the ocean filter marine snow from the water or scavenge it from the seabed. Over the past 20 years or so, NOAA scientists and others have measured the amount of useable material in marine snow and found that there is plenty of carbon and nitrogen to feed many of the scavengers in the deep sea.

The small percentage of material not consumed in shallower waters becomes incorporated into the muddy “ooze” blanketing the ocean floor, where it is further decomposed through biological activity. About three-quarters of the deep ocean floor is covered in this thick, smooth ooze. The ooze collects as much as six meters (20 feet) every million years. It is usually 289 meters (948 feet) thick, but can be up to nearly 10 kilometers (6.2 miles) thick.

Apparently, in the 1980s, they brought in snakes.

“the creatures arrived on the island accidentally in military cargo. ”

“The mildly venomous snakes can grow up to 10 feet long”

“The discovery that snakes will die when they eat acetaminophen was a huge step forward,”

“scientists drop mice packed with acetaminophen from helicopters into the jungle canopy.”

“outfitting the mice with cardboard wings and green party streams”

Read All About It

Enough that if i had a hundred of anything, i would have fifty in seventy years.

What are these anythings ? Phytoplankton in the ocean, who produce half the oxygen we breathe are declining at 1% a year. They die because the oceans change in a warming world. The world is warming because I and you put carbon dioxide in the air.

The phytoplankton eat carbon dioxide to make oxygen. So, a decline in phytoplankton means an increase in carbon dioxide, which in turn causes more warming and less phytoplankton and less oxygen and more carbon dioxide…

Eat local. Drive less. Insulate the house.

All the little live things

The firm-fixed price modification covers comprehensive Soyuz support, including all necessary training and preparation for launch, crew rescue, and landing of a long-duration mission for six individual station crew members.

In this contract modification, space station crew members will launch on four Soyuz vehicles in 2013 and return on two vehicles in 2013 and two in 2014.

Under the contract modification, the Soyuz flights will carry limited cargo associated with crew transportation to and from the station, and disposal of trash. The cargo allowed per person is approximately 110 pounds (50 kilograms) launched to the station, approximately 37 pounds (17 kilograms) returned to Earth, and trash disposal of approximately 66 pounds (30 kilograms).

How much faster? The robot working with silicon can build a semi-conductor on a six-inch-square plate of glass, plastic or flexible metal in about 35 minutes. It pivots and dishes like a point guard, sifts like a master chef, analyzes like a forensics expert and does it all while maintaining a vacuum seal on the entire process.

Simultaneously, it can analyze glitches and measure light absorption, while preparing the next half-dozen plates.

“It used to require us to go to, let’s see, one … two … three … four … five labs to do the same thing,” NREL scientist Ingrid Repins said.

And the silicon robot is one of just six such robots in six bays in NREL’s Process Development and Integration Laboratory (PDIL), the place where industry is starting to turn to test their newest cells.

The bay that uses silicon as the semiconductor for solar cells was the first to begin operating and holds all the speed and performance records so far.

Next to go on line were bays devoted to stand-alone characterization, integrated characterization and atmospheric processing.

The latest bay to start operating is the one that uses Copper Indium Gallium diSelenide (CIGS) as the semi-conductor in solar cells. Still being installed is the final bay, which will work with cadmium-telluride cells.

In each bay, the central transfer robot is the hub, operating like a jukebox, delivering the plate to chambers that can deposit micron-thin layers of chemicals to build the semi-conductors, or test and measure the growth of the crystals that make the cells.

Solar Companies Can Test Samples, Use Their Own Tools
Solar companies will be able to hook their own tools to the central robot and discover how their newest formulas compare. A vacuum transport tool can take the sample plates to the different, yet compatible, bays to see how an unusual process might bolster the power of a cell.

Solar companies know how to make solar cells in a dozen different ways — as shingles, as windows, as fanny packs, as attachments to space vehicles — but they constantly are searching for ways to lower costs and gain efficiency.

“The whole goal is dollars per watt,” Repins said.

President Obama has set a goal that solar energy become cost-competitive with coal and other fossil fuels by 2015.

“The gap is closing,” Repins said. “We’re getting closer. Already, First Solar is saying that for a large installation in southern California where electricity prices are relatively high, they are at parity now.”

NREL scientists are hoping their PDIL facility will help industry close that gap sooner by bringing lab-like precision to industrial-type processes.

R&D Agreement with Climax Molybdenum
For example, NREL last month signed a cooperative agreement with Climax Molybdenum of Empire, Colorado, which wants the lab to help test a new process of building sodium into the molybdenum layer of solar cells and then sputtering that sodium onto the CIGS layer.

Traditionally, the sodium leaches into the solar cell from the glass plate, but that’s not really a good way to do it because there is little quality-control in the glass-making procedure, Repins said.

For Climax Molybdenum, NREL will measure how well the company uses its tools to sputter the sodium from the molybdenum into the semiconductor, and how precisely it gets there.

“The assumption is that there will be more control getting sodium from the molybdenum than from the glass,” she said.

If it’s perfected, that’s another step toward lowering the cost of solar energy.

Solar cells are like mini-batteries, with three layers of thin films representing the two terminals and the current in between. The three layers together are about one-seventh the thickness of a human hair.

The middle layer, which absorbs the sun’s rays and acts as the current, is where the action is.

Some companies are sure CIGS will emerge as the best semi-conductor; others pin their hopes on cadmium telluride or the venerable silicon.

World Record; Now, How to Transfer It to Industry?
NREL two years ago set a world record for the efficiency of a thin-film solar cell, when its CIGS cell was able to convert to electricity 20 percent of the energy it absorbed from the sun. The record for a cadmium-telluride cell is 16.8 percent.

Today’s roof-top solar panels typically are able to convert about 10 or 11 percent of the sun’s energy, although there is a large range of between 8 percent and 20 percent efficiency.

Now, the challenge is to be able to layer a film of CIGS on commercial-sized solar panels without dropping down much from that 20 percent pinnacle.

Repins envisions that with the 20-percent formula as the template, in a few years companies can roll out kilometer-long sheets of solar cells and still achieve 16 percent efficiency — even as they strive to use the least expensive materials and put an emphasis on speed.

The difference between 11 percent and 16 percent is huge, because the cost savings multiply on each other, she said.

It means solar panels can be smaller and generate the same amount of energy, and that means lower materials costs, lower factory costs and lower installation costs.

Getting there — to reach a 16 percent efficiency level while making miles of thin-film cells a day — is the goal of the one-of-a-kind testing facility at NREL.

Sensors Can Read How Cells Are Growing
In the brightly lit PDIL on NREL’s campus in Golden, Colorado, scientists simulate the processes industry will use. The goal is to answer previously unanswerable research questions, while controlling and characterizing the surfaces of the cells, developing new techniques and devising new structures.

“The old way we used to do things, each layer required a different machine,” Repins said. “We would take out the substrate and put it into another machine.” Each time the plate was removed, humidity could weaken the cell and there were issues of cleanliness and contamination.

Now, the goal is a process that is seamless, spotless and transparent.

In each bay, lasers shine light on the cells and sensors can read how the cells are growing.

PDIL’s ultra-high-vacuum environment lets researchers study the role of impurities and defects, said NREL senior scientist Miguel Contreras. “We can do basic R&D at the material level. We can also develop analytical tools on site to test new plates and to test for quality.”

What combination of heat, metals, chemicals and time can grow the crystals to form the perfect cell? At one step excess copper is needed; at another, just enough sodium needs to leach into the middle layer.

The goal of all the depositing, analyzing and measuring is to be able to tell industrial partners why the cell isn’t growing as well as it should and what can be done about it.

“We do a post-mortem,” Repins said. For example, “‘We got 14 percent efficiency with these materials, why are you only getting 12 percent?’”

Companies want to know how they can turn the knobs to get the ultimate performance out of the cells. “This helps take that step toward telling them what to do in the process,” she said. “We can tell them, ‘this is what the sodium content should look like,’ for example. It’s one more clue.”

Bill Nemeth, a scientist in NREL’s PDIL facility, says he doesn’t have to wear a lab coat at work “because everything revolves around maintaining a vacuum,” and the researchers never come into direct contact with semi-conductors.

“We have the capability that no other place can duplicate,” Nemeth added. “This encourages cooperation.”

Goal: Fewer Impurities, Better Efficiency, Better Yield
The CIGS PDIL tool also was designed to do basic research and development on materials. The ultra-high vacuum environment allows scientists to study the role of impurities and defects, as well as what happens when the metals are deposited at the fast rate demanded by industry. That knowledge will help researchers develop analytical tools for quality control and to test for new plate materials.

“The system was designed to allow us to do things we could not do before, such as get a better look at impurities and the quality of materials, the different layers that compose the CIGS cell,” Contreras said. “It’s helping us understand better what is limiting our efficiencies, as well as learning how to improve industrial productivity.

“This gives us more insight into the physics and materials science of CIGS-based solar cells,” Contreras added. The fundamental research will “lead to better solar cell efficiency, process control, improved uniformity and improved yield.”

Learn more about NREL’s photovoltaics research.

— Bill Scanlon