Holding its fourth annual global investor day on the opening day of Solar Power International 2013, Yingli Green Energy provided for the first time a window into its longer-term cell efficiency roadmap to 2020.

Previously, Yingli Green had only provided its solar cell roadmap to include planned development through 2015. The company noted that the revealing of the extended roadmap was due to ‘increased visibility’ as to the cell efficiency improvements it expected to achieve in the timeframe, which also included higher cell efficiency targets for commercial-scale production of multicrystalline cells compared to previous guidance.

Yingli Green displayed its latest cell efficiency roadmap chart, which tracked commercial-scale p-type multicrystalline cell efficiencies from 17.6% in 2013 to 19% in 2020.

Yingli Green had cell conversion rates of 16.2% in 2009, 16.5% in 2010 and 17.0% in 2011.

Lab-based efficiencies of multicrystalline cells would be only 1% higher (20%) by 2020, consistently closing the gap between lab and real world fab production cells, which stood almost 2% difference in 2012.

‘PANDA’ cell efficiency gains

In 2011, Yingli Green reported an average cell conversion efficiency rate of 19.0% on PANDA production lines, which used N-Type wafers and a record cell conversion efficiency rate of 20.0% on the PANDA trial production line.

The new roadmap for PANDA cells continues a steady trajectory of improvements for both lab and fab-based cells through 2015. However, significant improvements are being planned in the 2016/17 timeframe when cell efficiencies are set to increase from 20.5% to 21.2% by 2017.

The biggest gains are expected through 2020 when efficiencies of the PANDA cell are targeted are reaching 23% in commercial production. Again, lab to fab differences would have narrowed to just 1%.

A key part of the reason behind the lab to fab efficiency variance narrowing was said to be due to continuous improvements in operating efficiencies of manufacturing processes, which also provided cost reductions.

Yingli Green has continued to increase R&D staffing levels over recent years, which reached a record high for the company and the industry sector of 1,464 in 2012.

One of the positive side-effects of the increased staffing levels has been a significant jump in patent filing and issued patents. The company noted that cumulative patents had reached 617 in 2012 but had already reached 734 in 2013, with 1121 applied for.

The company stressed that its strong R&D capabilities were a key differentiator going forward.