The main reasons cited were new cost pressures due to oversupply; more reasonable polysilicon prices, which have helped to boost TFPVs main competitor, crystalline silicon PV (c-Si PV); and the incomprehensive climate agreement reached at Copenhagen last December, which, due to the lack of international goals for greenhouse gas reduction, and the reduced likelihood for carbon taxes, removed two factors that were in the business plans of many entering the field of PV.
Substrates and encapsulation, especially for flexible applications, represent areas where there are many opportunities to improve both dimensional stability and thermal budget to support wide process margins for absorber layer deposition, stated the report. However, the challenge for substrates and encapsulation is to provide higher performance at either equivalent or lower prices compared to current materials.
It went on to say that transparent conductive oxides (TCOs) for electrodes remain problematic, but there are opportunities available for incremental improvement. Each of these areas represents opportunities for innovative materials-related solutions, but the solutions must always keep cost as a foremost consideration since TFPVs advantage is in its lower cost.
Thin film silicon
In terms of thin film silicon, NanoMarkets says it must accelerate its roadmap if it wants to remain relevant and avoid becoming a legacy technology. Having been the dominate TFPV technology, it was usurped by cadmium telluride (CdTe) its challenge is now to increase efficiency, without increasing costs.
This will become even more critical as higher efficiency CIGS modules ramp to volume production over the next couple of years, explains the report. As a mature technology, a-Si PV has less room to grow with current tandem and triple junction cells nearing their practical efficiency limits. In addition to its lower conversion efficiency, it has lost the low-cost TFPV crown as aggressive cost cutting in CdTe has eclipsed TF Si PVs for low cost/watt.
The report found that established TF Si operations with low cost structures have mostly survived, but much of the smaller turnkey suppliers have capacity that was recently built and now sits idle or was never completed.
In terms of the CdTe thin film market, which is led by First Solar, NanoMarkets says that it has fared the best, having managed to be profitable through the downturn.
While there are a few other companies trying to capture market share, the research company believes they will have a hard time competing against First Solar. It says that one option may be for the companies to expand into new device innovations, such as flexible- or building-integrated cells. But, said the report, First Solar is likely to have the upper hand even in developing new products. The company has an R&D department and has been rumored to have purchased CIGS precursors, suggesting it has considered tandem cells.
It went on to say that the growing use of tellurium (Te) presents an opportunity for companies in the copper and lead refining industry, since it is primarily a byproduct of refining these ores. As a result, the development of additional Te capacity will be important to ensuring an adequate supply. As tellurium prices rise this opportunity will become more lucrative. A critical eye will need to be kept on Te supplies out of Apollo Solar to help understand if its Te mine resources are viable long-term sources of Te.
Copper indium gallium diselenide (CIGS), on the other hand, has been limping along, but several recent announcements such as Lux Researchs prediction that the technology is positioned to overtake crystalline silicon in profitability by 2013, as the process stability is improved, point to green shoots of growth.
NanoMarkets predicts that in time, the use of ink to print the CIGS layer will produce a flurry of development activity. The process still needs to be refined however, and it remains to be seen which companies will be able to deliver modules in high volume. The research company cited Nanosolar as one to watch, following recent changes which have seen the company focus on new execution on the manufacturing and production side, with a one megawatt demonstration facility now on line.
In the sluggish PV environment that NanoMarkets predicts for the next few years, ultra high-capacity factories may need to be idled frequently or run substantially below capacity, making profitability difficult. As an example of this, much of the a-Si turnkey PV capacity that was built in 2006-2008 either sits idle or was not finished. Near term there may not be the demand to justify the ultra high- capacity factories necessary to achieve the full entitlement of the printed CIGS solution, said the report.
NanoMarkets went on to say that, as with CdTe, the development of CIGS tandem cells is an important opportunity for performance improvement with little cost increase.