Factory delays spurring higher cell efficiencies, finds NPD Solarbuzz

Spooked by the lingering legacy of overcapacity and threatened by ongoing trade disputes that continue to spread uncertainty throughout the solar ranks, many solar PV cell manufacturers are turning their attentions to improving manufacturing processes as they chase ever greater efficiencies, says NPD Solarbuzz.

The analysts’ latest PV Equipment Quarterly report suggests that the power rating of industry standard 60-cell multicrystalline silicon-based modules could reach 275 W within 12 months as focus switches to research and development in the wake of new facility construction delays and perennial industry pressure to improve.

These crystalline (c-Si) modules continue to be the dominant technology across the global industry, accouting for 92% of all module production in the second quarter of the year, the study found. Thin-film technology comprised the majority of the remaining capacity, led by First Solar and other suppliers.

Among c-Si producers, 68% of global capacity is derived from cells made with lower-cost, lower-quality mult-c-Si wafers, which are used extensively by the world’s leading PV suppliers such as Yingli, Trina Solar and Renesola.

However, following the overcapacity that damaged the sector in 2011 (when between 4-6 GW of C-Si cell capacity was added, on average, every quarter), the number of c-So cell factories built decreased in 2012 and 2013. During this dormant period, cell manufacturers focused on reducing costs, says NPD Solarbuzz, by upgrading printing equipment used within process steps on the front side of the cells, reducing the overall quantity of silver paste – a significant cost – used during production.

With the savings, cell manufacturers were able to invest in the use of higher quality multi c-Si wafers, which elevated the power rating of the standard 60-cell c-Si module to 265 W – all without the addition of significant process step changes at the cell stage.

"To move existing silicon-based cell capacity further forward now requires new technologies to be implemented, which has the potential to drive solar manufacturing into the first widespread technology buy cycle seen within the industry," said NPD Solarbuzz VP, Finlay Colville. "The solar PV industry previously operated without a clear technology roadmap, which is no longer an option in the rapidly growing solar PV industry."

Factory delays and capacity upgrades

It was expected that new solar cell factories in Taiwan would come online during the second half of the year. "The threat of import duties on Chinese and Taiwanese manufactured components shipping to Europe and the U.S., however, has caused additional delays and uncertainty," added Colville.

Idle hands as a result of that uncertainty have been guided instead towards efficiency enhancement techniques, including the introduction of new advanced process stages during the rear-side fabrication of c-Si solar cells. Capacity upgrades this year have spurred solid growth for specific cell variant using new equipment in rear-side cell processing (passivated emitter and rear cell, PERC).

According to NPD Solarbuzz, the PERC upgrade alone could add 10 W to a typical 60-cell c-Si module, and as much as 15 W to mono c-Si versions, taking typical modules to 275 W – an achievement that would lower system installation costs and improve profit margins because fewer solar modules would be required per installation.