Scientists at Empa, the Swiss Federal Laboratories for Materials Science and Technology, have developed thin film solar cells on flexible polymer foils with a new record efficiency of 20.4% for converting sunlight into electricity.
The cells are based on CIGS semiconducting material .The technology is currently awaiting scale-up for industrial applications.
The team was led by Ayodhya N. Tiwari, who has helped improve alongside PhD students Adrian Chirila and Fabian Pianezzi the cell’s efficiency record from the current 20.4 % from a May 2011 record of 18.7%.
The cell efficiency value was independently certified by the Fraunhofer Institute for Solar Energy Systems (ISE). Empa’s new record efficiency for flexible solar cells now even exceeds the record value of 20.3% for CIGS solar cells on glass substrates – and equals the highest efficiencies for polycrystalline silicon wafer-based solar cells. "We have now – finally – managed to close the "efficiency gap" to solar cells based on polycrystalline silicon wafers or CIGS thin film cells on glass", says Tiwari.
“Now it is time for the next step, the scale-up of the technology to cover large areas in a cost-efficient roll-to-roll manufacturing process with an industrial partner”, said Gian-Luca Bona the Director of Empa. For this purpose, Empa is collaborating with Flisom, a start-up company involved in industrialization of flexible CIGS solar cells.
First Solar acquires Solar Chile
First Solar has acquired Solar Chile, a Santiago-based solar development company in which Fundación Chile was an early investor. The recent deal culminates a strategic working alliance the two companies formed in October 2011.
Solar Chile has a portfolio of early- to mid-stage utility-scale photovoltaic (PV) power projects totaling about 1.5 gigawatts (GW) in Regions I, II, III, and XV in northern Chile, including the Atacama Desert region, which offers the highest solar irradiance in the world.
"We have been very impressed by the quality of the Solar Chile team and the projects they are developing, and we believe that together we will bring even more value to the Chilean market," said Jim Hughes, First Solar CEO.
"Combining Solar Chile's market knowledge and promising project portfolio with First Solar's resources, technology and strong execution track record offers Chile a rapid and proven path to add significant solar generation capacity, helping to meet high energy demand and support economic growth," said Hughes.
"Chile faces a growing energy demand from its sustained economic growth," said Hernán Cheyre, Executive Vice-President of CORFO, the Chilean government's economic development agency. "Solar energy provides a sustainable and clean energy source that takes advantage of our outstanding clear skies and irradiance.”
MicroTech launches thin film production tool
Silicon Valley wet process station supplier, MicroTech, has launched a product line specifically designed for high throughput processing of thin film solar cells. The company claims that its cells can produce substantial cost reduction and cell integration by processing an entire array of solar cells on a single substrate.
The MicroTech TF 1200 production tool can process substrates up to 2 meters in size. It also offers benefits, such as low water consumption with strict control and recycling of water through a patent-pending technology; effective particle filtering and modular design for process flexibility and ease of change; upgradeable in the field to name a few.
The business has developed and manufactured a series of modular systems that use the latest technologies to further reduce costs and save chemistries. Modules are available for all major solar thin film process steps including clean, develop, etch and ultrasonics.
XsunX begins CIGs processing
XsunX has started to process copper, indium and selenium films with its CIGSolar TFPV solar cell evaporation system, it has been reported.
The company has been testing and calibrating the deposition source technology in its new evaporation system so that it can transition to processing CIGS.
XsunX CEO Tom Djokovich said that the company has begun the last phase to prepare for its CIGSolar TFPV solar cell evaporation system for customer demonstrations with the initiation of CIS film processing.
"This represents a major step forward and allows us to then transition to CIGS films and the completion of the system's readiness for demonstrations," said Djokovich.
DayStar looks to buy seven Greek projects
Thin film developer, DayStar Technologies, has entered into an agreement with Arxikon Construction that would entail DayStar to acquire seven solar projects from Arxikon Construction Company in Greece.
The solar parks, which are located in the industrial northern region of Greece, are 1MWp each.
DayStar will have 200 days to conduct its due diligence, regulatory approvals and financing for the acquisition, which has a contract value of €75m over a period of 20 years.
The solar parks’ assets are valued at close to €21m, according to reports, with an annual power output estimation of 10.85GW per year.
The solar parks were constructed with Bosch monocrystalline solar cells and SMA Inverters and are fully equipped with data acquisition systems for 24/7 monitoring.
Panasonic HIT PV modules pass PID test
Panasonic received promising news recently following a bespoke potential induced degradation (PID) characteristics test developed by the Fraunhofer CSP to account for Panasonic’s unique HIT solar modules.
According to a Panasonic, the test included negative and positive voltages, whereby 5 modules were subjected to +1,000 volts for 48 hours at a temperature of 50 degrees Celsius with 50% relative humidity and 5 modules at -1,000 volts over 48 hours. According to the company, no evidence of PID was observed.
Dr. Matthias Ebert, Head of the Group Module Reliability at Fraunhofer CSP, said that because HIT modules differ from standard modules, he challenge was to develop a test method that would respect this. Ebert said that by testing for both positively and negatively charged voltages, he and the team were able to attest to the PID resistance of HIT photovoltaic modules.
Panasonic uses thin monocrystalline n-type silicon wafers surrounded by ultra-thin amorphous silicon layers, which do not require insulating layers, unlike conventional crystalline silicon-based solar cells, which can collect electrical charges near an the insulating layer and PID characteristics.