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Over 86,000 terawatts of solar energy reach the Earth’s surface each year- enough to satisfy current global energy demand 1000 times over.  In 2008, solar electric power amounted to a mere 0.2% of global energy produced but it is at a tipping point with a growth rate of 40% per year. Exponential growth, enormous solar resources and the global economy's unquenchable demand for electricity increasingly position photovoltaic power as vital to 21st century technology.

In this rapidly changing industry, the Solar Power Lab stands-out as having some of the most experienced researchers in the field.  This, coupled with state-of-the-art facilities and institutional support, gives SPL the solid foundation necessary to push the boundaries of what has become a $20 billion sector of the economy.

Arizona State University’s Solar Power Lab serves a staging ground for the new technologies and ideas that will move us forward in our quest for a more sustainable society. 

The Solar Power Lab is also committed to education.  Check out our electronic book for information on photovoltaics, solar industry, and the physics that govern them.  

The Solar Power Lab has numerous capabilities such as:

  • A full pilot line for 6 inch solar cells with an average efficiency of 18.5% for diffused cells
  • New 6 inch solar cell line doe 22%+ heterojunction cells.
  • Extensive capabilities for silicon solar cell characterization
  • Molecular Beam epitaxy system for nano-structured solar cells

News


Welcome

Over 86,000 terawatts of solar energy reach the Earth’s surface each year- enough to satisfy current global energy demand 1000 times over.  In 2008, solar electric power amounted to a mere 0.2% of global energy produced but it is at a tipping point with a growth rate of 40% per year. Exponential growth, enormous solar resources and the global economy's unquenchable demand for electricity increasingly position photovoltaic power as vital to 21st century technology.

In this rapidly changing industry, the Solar Power Lab stands-out as having some of the most experienced researchers in the field.  This, coupled with state-of-the-art facilities and institutional support, gives SPL the solid foundation necessary to push the boundaries of what has become a $20 billion sector of the economy.

Arizona State University’s Solar Power Lab serves a staging ground for the new technologies and ideas that will move us forward in our quest for a more sustainable society. 

The Solar Power Lab is also committed to education.  Check out our electronic book for information on photovoltaics, solar industry, and the physics that govern them.  

The Solar Power Lab has numerous capabilities such as:

  • A full pilot line for 6 inch solar cells with an average efficiency of 18.5% for diffused cells
  • New 6 inch solar cell line doe 22%+ heterojunction cells.
  • Extensive capabilities for silicon solar cell characterization
  • Molecular Beam epitaxy system for nano-structured solar cells

QESST - Terawatt Challenge.

 

New Solar Cell Tester

ASU took delivery of a new advanced solar cell efficiency tester from Sinton Instruments this week. The new tester is a FCT-450 and is an upgrade of our previous tester also from Sinton Instruments. A significant advantage of the new system is the ability to measure smaller area cells, a broader range of temperature measurements and the extraction of substrate doping from the completed solar cell.

 

Like the previous model, the new tester is capable of autmoated SunsVoc and LightIV measurements giving unambigous extraction of cell series resistance and shunt resistance. The tester uses a voltage modulation technique to neutralize the capacitive effects in high performance solar cells. With our record voltages we experience decay lifetimes of 2 ms in the completed cells. Most testers have problems with our cells as the sweep rate is a similar order of magnitude. We have found that the voltages from the FCT  match those measured at NREL even for cells where the voltage approaches 750 mV.

All About Solar on YouTube

All About Solar cells is a series of lectures on the use and fabrication of solar cells.

The solar cell industry continues to grow in leaps and bounds and will have a major impact on energy production in the future. The Solar Power Laboratory at Arizona State University has been running the student led pilot line for the past six years as part of the QESST research Engineering Research Center and more recently included the NCI-SW. The line has had taught over 200 people how to make a solar cell in hands on setting where the learners get to make a solar cell from start to finish. Many of the learners are already experienced in the industry while for others it is their first time in a laboratory.

One of those students, Edward LeBeau, wanted to give something back to the pilot line. He recognized that while there were lots of resources on the fabrication of solar cells they weren’t always relevant to what happens in the lab.  “The Pilot Line was a great introduction to research during my first year at ASU. I wanted to give something back, and thought a set of introductory lectures for people who are new to solar would be a good contribution,” said Eddy. Using resources from SPL, he developed a series of lectures to provide the background information to the fabrication of the cells that we make. He starts out with an overall introduction on the solar cell industry and then continues through cell fabrication and characterization.

These lectures are now available for free on youtube. We hope that they will be useful not only for people learning how to make solar cells at the ASU pilot line but also for people who want an introduction to the way solar cells are made.

Each lecture is about 10 minutes in length and the whole series takes about an hour.

Quantum Energy and Sustainable Solar Technologies (QESST) is an Engineering Research Center (ERC) sponsored by the National Science Foundation (NSF) and the U.S. Department of Energy (DOE) that focuses on advancing photovoltaic science, technology and education in order to address one of society’s greatest challenges: sustainably transforming electricity generation to meet the growing demand for energy.

Nanotechnology Collaborative Infrastructure Southwest ( NCI-Southwest) supports the advanced tool-set, faculty expertise, and knowledgeable staff required by academic and industrial users performing research at the frontiers of nanoscience and engineering.

 

Industry and Innovation Program


Regher Founder,
Dr. Stanislau ‘Stas’ Herasimenka

Regher Solar LLC, a QESST spinout company, recently announced reaching a cell efficiency of 21.3% as confirmed by the National Renewable Energy Laboratory in Colorado. Regher is cofounded by Dr. Stanislau ‘Stas’ Herasimenka, a postdoc and QESST alumni.

While at QESST, Stas developed all aspects of silicon-heterojunction technology from wafer cleaning to commercial PV panel prototyping. With five patents and two disclosures to his name, Stas intends to develop a patent portfolio that will help create a defensible market position for Regher.

 

The cell with 21.3% efficiency had open circuit voltage of 730 mV, short circuit current of 38.5 mA/cm2 and fill factor of 75.8%.  “We expect to quickly increase the efficiency of our cells to over 22.5%, which we are routinely measuring on 100 cm2 aperture area cells,” Stas said. “This will open a route to potential customers from the PV industry interested in scaling next generation manufacturing technologies for high efficiency silicon solar cells.”

Pictured below is the photo of silicon heterojunction solar cells with plated copper contacts developed by Regher Solar in collaboration with QESST Scholars at the QESST Solar Power Laboratory.  

 

 

Undergraduate Presents at IEEE Conference

QESST scholar Antony Aguilar was invited to present an extended oral talk at the 2016 IEEE Photovoltaics Specialist Conference (PVSC) in Portland, Oregon. Antony presented the paper, Development of Cu Plating for Silicon Heterojunction Solar Cells, representing the High Efficiency Silicon Solar Cell (HESSC) team directed by QESST faculty, Stuart Bowden. Co-authors included other QESST scholars and industry partners from Technic (Krystal Munoz, Lynne Michaelson, and Tom Tyson). The presentation described an alternative metallization to the standard low temperature Ag paste for Silicon Heterojunction Cells (SHJ) cells.

 

Impacts and Benefits

  • Antony reported the results of a study comparing various patterning and plating methods for the deposition of Cu electrodes on transparent conductive oxides for silicon heterojunction solar cells. The best silicon heterojunction cell with Cu contacts directly electroplated on the sputtered Ag seed achieved 21.9% efficiency on 153 cm2area.
  • A talented QESST undergraduate scholar transitioned to an ASU graduate program in Electrical Engineering with experience and confidence

Explanation and Background 

Presenting the extended oral talk at PVSC is an unusual honor for an undergraduate student. It was Antony Aguilar’s first paper presentation; “I nearly passed out before presenting on the day of the conference because I was so nervous - I get nervous just thinking about it”.  Antony received a lot of support in preparing to present, particularly from the HESSC lab manager, Stanislau Hersasimenka. Antony also appreciated the feedback he received from the PVSC audience, “Some people stayed after to talk to me about my research. They wanted to know what future work I was doing. They approached me like an experienced researcher.”

Antony was born in California, but grew up in Mesa, Arizona. Following high school, he enrolled in community college with an interest in forensic science, but soon switched to electrical engineering. Bouncing between four colleges to fulfill credit hours, Antony took numerous classes while working Dave & Busters to support himself. “I worked there way too long and decided if I was going to do anything with my life I had to quit.” After successfully applying to and participating in the QESST REU, Antony transferred to Arizona State University and began working in the HESSC lab. There he became known for fixing lasers, designing Arduino circuits, and installing new safety measures for lab equipment. “That’s when Stas asked me if there was a way to contact probes to a solar cell. Little did I know that would become an IEEE paper and even my dissertation research.” Antony transitioned to graduate school in fall 2016.

In addition to being a committed scholar, Antony participates often in QESST outreach. “I think it’s important to inspire the next generation... I know for a fact if we were missing one of these brilliant people who work at our lab, there would be a huge gap in research. Everything we do here [at QESST] is important; the more people who do it the more chance we have of developing better solar cells, better, safer, cheaper products… I wish QESST came to my high school; I probably would have got interested a long time before I did. I was good at math and science, but there wasn’t much to hold my interest. If I had some inspiration like that, seeing what you could do with science, I might have got here a lot sooner.”

Ultra-High Temperature Solar Cells

Solar cells typically operate at temperatures below 100 °C. A new class of 'refractory' solar cells was presented at the 43rd IEEE Photovoltaic Specialist Conference in June 2016. These new cells are stable at tempertures over 600 °C.

In addition to applications in CSP-CPV hybrid plants, these cells open up new application areas for solar cells. Those applications include  power beaming for wireless recharging of electric UAV’s, high temperature cells for space probes to Venus and Mercury, and deployment in nuclear-photovoltaic hybrids.

 

The cells were produced by a team of scientists from QESST at ASU and corporate partner Photonitride Devices, Inc. have produced a solar cell capable of sustained operation at temperatures of 600°C, a record in the field. These devices, leveraged on blue-LED technology, are made possible with InGaN quantum wells in a GaN diode. Due to the nature of these cells ability to produce power while at such extreme temperatures, we have identified them as new class of solar cells, “refractory solar cells.” These results and corresponding analysis were presented as a talk at the 43rd IEEE Photovoltaic Specialist Conference in June 2016, and submitted for publication in the Journal of Photovoltaics.

This technology expands the range of environments into which photovoltaic technology can be deployed. The motivation application for this work was as a thermal topping cell on the receiver of a CSP (concentrated solar power) power plant. This allows direct conversion of electricity from sun-light, a more efficient process than the use of light to heat to mechanical energy to electricity. Additionally, as a thermal topping cell all inefficiencies become heat which transfers to the thermal receiver regardless.

Explanation and Background:

GaN and related InGaN materials have enabled the LED lighting revolution our society is currently experiencing. The industry surrounding these semiconductor technologies has grown exponentially. This technology also has use as an enabling material for solar cells. By modifying the structure of a blue LED, we are able to make InGaN solar cells.

Furthermore, the GaN and InGaN materials are naturally stable at high temperatures (both chemically and electrically). This is due the strength of the group III-N atomic bonds and the wide band gap of the material. The end result being that these materials are capable of creating photovoltaic devices operable at temperatures far hotter than any other PV technology

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Mexico I-Week

The Tecnológico de Monterrey came to the QESST for a two day intensive session on the use and operation of photovoltaic devices.The majority of the students were enrolled in the Architecture schools at Tecnológico de Monterrey in Mexico and were exposed to the more engineering side of photovoltaics. The students each fabricated a solar cell module and then used the module in outdoor testing. As photovoltaics is an international technology the Solar Power Labs was pleased to be able to host the Mexican students and looks forward to further collaborations in the future.

Over the course of two days, QESST faculty and Scholars taught twenty-one architectural undergraduates and two faculty members how to design their own Photovoltaic Module. Undergraduate students from the Tecnologico de Monterrey worked with sixteen QESST scholars during a two-day workshop hosted by the Solar Power Lab in Tempe, Arizona. Beginning with an interest, but very little knowledge about solar energy the Tecnologico de Monterrey students ended the workshop having built and tested their own silicon cell modules. In addition to mastering the processes needed to build and test a module, each student had an opportunity to explore every aspect of a photovoltaic system, at the level of individual cell performance to solar installation design.

A large cadre of QESST Scholars, faculty and staff were required to provide this intense two- day workshop. Director Honsberg provided an introduction to photovoltaics for the novice students, Dr. Harvey Bryan from the Design School at ASU discussed the influence of utility costs, location of solar panels, usage amounts based on demographics, as well as aesthetics of solar installation design. Dr. Mariana Bertoni bought all of the information home, ensuring students left with confidence in their new knowledge and a passion for photovoltaic design.

 

Research Experience for Undergraduates (REU)

Twelve students just finished the latest course on the manufacture of solar cells at ASU. At the completion of the course the students were able to complete the manufacture of high efficiency solar cells on the pilot line at the solar power labs. Half the students came from across the US as part of the QESST engineering research center, and the other half were from the SUN IGERT program at ASU.

 

 

John Mitchell, Industrial Liaison for QESST, and the Fulton Schools Career Center lead a 4 hour workshop and luncheon. The focus of the workshop was entrepreneurship. Guest speakers, Brian Peterson of Rafael Tirado & Associates discussed resources available for startup and spinoff companies, legal issues regarding international partnerships, establishing LLC and S-Corp, and Wiley Larsen of ASU discussed specific resources for supporting entrepreneurship available to both ASU and partner school students through the Entrepreneurship initiatives at ASU. A highlight of the event, was a presentation by two chemical engineering students who developed their own startup, and have successfully gone to market. The product we discussed was an intervention to aid the purification and portability of water, specifically designed to be used in the developing world. Joyce Donahue from the Fulton Career Center, provide practical advice to our students concerning etiquette for formal dining, the students then had the opportunity to use these skills during a formal luncheon with members of industry, QESST faculty, staff, and SPL graduate students.

Christiana Honsberg wins William R. Cherry Award

Solar Power Laboratory director Professor Christiana Honsberg wins the 2015 William R. Cherry Award. It will be presented at the 2015 Photovoltaic Specialists Conference in New Orleans on June 15 2015

Dr. Christiana Honsberg, Distinguished Professor of Electrical Engineering and Director of the Solar Power Laboratory at the Arizona State University, will be receiving the Cherry Award in recognition for her multiple contributions to the advancement of photovoltaics. Her notable contributions include the pioneering of advanced PV concepts ranging from the development of a generalized thermodynamic theory for determining efficiency limits of solar cells to making seminal advances in the understanding of intermediate band, interband and quantum well approaches.

Dr. Honbserg is also a co-inventor of the so-called “Very High Efficiency Solar Cell (VHESC)” that combines optical/solar cell architectures that produced a sum-of-the efficiencies result of 42.8%, she has contributed to the advancement of III-Nitride solar cells, and she is responsible for inventing and licensing of methods to produce high performance Si solar cells. Dr. Honsberg is also the co-developer of the popular PV CDROM educational online course that is now widely used in solar cell education at universities across the world. Prof. Honsberg also serves as Director and Lead Investigator to the first US multi-Institutional Engineering Research Center (ERC) on Photovoltaics that is jointly supported by the U.S. National Science Foundation and the U.S. Department of Energy, and where she leads and coordinates the ERC’s R&D efforts across some 30 national and International academic and industry partners with a focus on enabling solutions to harness thesolar power in economically more viable and sustainable ways. Prof. Honsberg will deliver her Cherry Award acceptance talk on Monday June 15 at 11:30 during the Conference Opening Keynote Session.

 

About the Award

This award is named in honor of William R. Cherry, a founder of the photovoltaic community. In the 1950's, he was instrumental in establishing solar cells as the ideal power source for space satellites and for recognizing, advocating, and nurturing the use of photovoltaic systems for terrestrial applications. The William R. Cherry award was instituted in 1980, shortly after his death. The purpose of the award is to recognize an individual engineer or scientist who devoted a part of their professional life to the advancement of the science and technology of photovoltaic energy conversion.

Summer Research Program Starts

Each summer we run a research program for participants to learn about solar cell manufacturing and to conduct research on improving solar cell performance. After going through basic training on how to make a silicon solar cell, the larger group splits into teams to research a special topic on solar cells.

This year the program has significantly expanded from previous years. We now have 24 participants taking the program under the guidance of five graduate student mentors. We have also extended to the time that people work on the projects to eight weeks.

Solar power is booming and we use the summer program to educate on the technology behind the solar cell.  To reflect the broad use and impact of solar power in the community,  the program is a very inclusive environment and participants come from a range of back grounds and varied educational levels. Young Scholars from high schools get their first taste of what it is like to do research in a university cleanroom. The majority of the program consists of undergraduate students from both community colleges and universities. These students get to explore new concepts in solar cells design an fabrications. We also have STEM teachers who take what they learn over the summer back to their classrooms. At the graduate level, students who have been studying the device physics of photovoltaics have the opportunity to make a solar cell on a pilot production line and explore the issues and challenges involved in taking a new technology from a lab and into commercial production.

From the laboratory to the classroom.

One of the features of the 2015  Summer research programs is making connections between basic solar energy research and community education. Kyle Rawlings, a faculty member at Scottsdale community college, not only participates as a full member of the research team over the summer but also recruit students from his physics classroom to participate in a research. Kyle investigates how engineers apply the physics concepts he teaches every semester, alters his coursework to ensure students who are coming from his classes have the foundational knowledge to be able to participate in solar energy research, and reflects with other instructors but best peak teaching practices. Kyle indicates that this program rejuvenates him every summer. Kyle's enthusiasm for this program spread to his students not only who apply for and participate in the QESST summer program. Exposure to research and university life motivate students to complete their associate degrees and continue on to engineering bachelor's programs. One of the mentors for our undergraduate program, Michael Minjares, was a community college participant last year. After transferring to ASU he contingent to do research in the lab will be spending the summer working with community college students on their research projects. Students participating in the full 10 week research program will be presenting their work at the crystalline silicon workshop.