CIGS On The Record

Copper Indium Gallium Selenide (CIGS) thin-film module maker Avancis announced a new record level performance for its PV module. The champion PV module attained an efficiency of 17.9%, which according to the German-based company is the highest ever reported conversion efficiency so far for its kind. This world record performance, which is certified by Fraunhofer Institute for Solar Energy Systems (ISE), has been attained for a module aperture area of 622 cm2. The module measures 30 x 30 come and has a power rating of 11.16 W. Avancis' achievement supersedes Solar Frontier reported record conversion efficiency of 17.5% for a designated illumination area of a 808 cm2 module.

Following roadmap targets

A white paper jointly prepared by the major research institutes and PV manufacturers involved in CIGS technology roadmap expects full area module efficiency to cross 18% in 2018. In this regard, Avancis' latest achievement of 17.9% aperture area is a step towards that target, although their record module is quite a bit smaller than a commercial module. However, according to Avancis CTO Jörg Palm, transferring this results into production would mean that the PowerMax module series of the company with a size of 1 m² would have a rated power of 170 W. The commercially available 3.5 generation SolarMax modules come with a maximum label wattage of 140 W, corresponding to 13.3% for total area or 14.7% efficiency for aperture area. This is actually a rather wide gap between aperture and total area efficiencies when compared with the other dominant thin-film technology CdTe – First Solar's modules show a gap of about 0.2% absolute.

Commercially feasible

Avancis' champion module, which measures 30 x 30 cm2 and features improvements in several aspects, is still close to the company's commercial products. The module is based on mass-produced CIGS absorber from the AVANCIS production plant in Torgau. In addition to optimizing the indium-based buffer layer, its deposition is accomplished in completely dry vacuum coating processes with enhanced material yield. The most important improvement that results in this performance boost is to reduce the cell width and optimizing the zinc oxide. The laser process was also fine-tuned to reduce the dead zone between the series-connected cells. All these improvements resulted in about 1.3% absolute gain over the previous record level aperture area efficiency of 16.7% that was reported in January 2014.

Quickly growing

Avancis, which is owned by CNBM, China's largest building materials group, operates facilities with 120 MW in Torgau, Germany. It also started a 100 MW factory in Korea as part of a joint-venture with Hyundai. Last October, Avancis announced to start production of a new 300 MW facility in Benbu, in the Chinese province of Anhui in 2017, which in steps is said to be expanded to 1.5 GW.