Dec 6 2012
Silevo, Inc., a solar cell innovator and photovoltaic (PV) solar module manufacturer, today announced that its proprietary tunneling junction cell architecture has achieved 22.1 percent cell conversion efficiency, as measured by Sandia National Laboratories with Silevo’s production materials and full-size substrates.
This measurement validates that Silevo’s Triex® PV modules demonstrate one of the highest energy densities in the industry. Moreover, it validates Silevo’s roadmap and plan to achieve 24 percent conversion efficiency in mass production over the next few years.
In addition to demonstrating excellent conversion efficiencies, Triex hybrid technology is demonstrating real-world energy harvest benefits: California Energy Commission (CEC)’s test results rank Silevo’s Triex modules first among modules that employ crystalline silicon (c-Si) layers. The CEC compiles a list of top modules, taking into consideration PV-USA Test Conditions (PTC), which classify module performance at a more realistic, real-world environmental condition of elevated air temperature. Typically, modules are categorized by Standard Test Conditions (STC), which are measured at a much lower, controlled lab cell temperature. CEC’s PTC/STC ratio (real-world performance divided by controlled lab environment performance) for Triex modules ranked first at 93.49 percent, thanks to the technology’s inherent value of using materials and a device structure with very low cell temperature coefficients. As a result, its real-world performance is world class for technologies that employ c-Si layers, and its performance ratio exceeds that of all other advanced technologies that employ heterojunction, interdigitated back contact, as well as selective emitter techniques that are being commercialized by players today.
“We are very pleased to be executing according to our technology roadmap by continuing to drive higher power density in achieving 22 percent conversion efficiency. In addition, placing first in a performance ranking in a highly regarded, real-world environment PTC metric further validates the performance characteristics of our proprietary technology,” said Zheng Xu, CEO at Silevo. “With our high volume manufacturing capacity ramping, Silevo is truly demonstrating that a new paradigm of high performance to cost ratio modules can further reduce system costs and levelized cost of electricity.”
Silevo continues to focus on characterizing quality and reliability performance of its Triex module technology. Triex modules recently passed stringent Potential Induced Degradation (PID) and extended Damp Heat (DH) testing, during which modules are biased at high voltages and also exposed to elevated temperatures and humidity levels. The PID and DH tests were conducted by Renewable Energy Test Center (RETC), a TÜV SÜD America’s partner for PV testing.
“RETC is proud to announce that Silevo has successfully passed PID testing on their Triex modules (biased DH: 85 degrees Celsius + 85 percent Relative Humidity (RH) + negative system voltage of 1,000 volts) for a duration of 1,500 hours with minimal degradation well below required thresholds. Silevo’s Triex modules have also completed extended DH testing with 2,000 hours of 85 degrees Celsius and 85 percent RH, twice the IEC 61215 requirement with negligible degradation,” said Cherif Kedir, senior vice president of engineering and operations at RETC. “Silevo's high efficiency modules with hybrid solar cells powered by tunneling junction technology have proven reliable, well beyond certification requirements.”
While other solar manufacturers have achieved PID compliance, their products’ exposure times to these elevated conditions ranged between 100 and 200 hours. In Silevo’s case, the technology was exposed seven to 15 times longer, further demonstrating the company’s detailed focus on long-term reliability performance. By combining reliability, high efficiency, high energy harvest and cost-effectiveness into the Triex module technology, Silevo is paving the way to shifting solar PV towards a sustainable marketplace.