Search sponsor
Search sponsor
Amorphous-silicon thin-film PV has been around since the time when Jimmy Carter admitted to having lust in his heart (along with solar on the White House roof), and the words "personal" and "computer" rarely ended up conjoined. The first truly commercial TFPV was always going to be the next big thing, ultimately replacing crystalline silicon as the premiere photovoltaic material.
Well that didn't happen. But the future has never looked as promising for SiTFPV as it has over the past few years. It has taken another couple of decades, but amorphous--sometimes with a little germanium blended in, or in combo with its progeny, microcrystalline--is actually in the conversation about rewriting the solar power playbook.
The clusterbomb of companies like Sharp, Sanyo, and ECD Uni-Solar ramping hundreds of megawatts of tandem/multijunction thin silicon lines along with the turnkey trio of Applied Materials, Oerlikon, and Ulvac offering start-ups a lower-risk entry to high-volume PV module making--with the polysilicon shortage thrown in as a market sector accelerant--has given SiTFPV the kind of disruptive status that only its true believers once dreamed of.
At least one market research company believes that the best days of SiTFPV (or as they might initialize it, TFSiPV) are ahead of it. In the new report, "Materials for Thin Film Silicon Photovoltaics," NanoMarkets sees SiTFPV as the dominant thin film today and for several years into the future. Although First Solar single-handedly has put CdTe into the aforementioned conversation, skinny silicon still held on to the lion's share of the TFPV veldt in 2008 (which represented 23% of the overall PV market last year), with 54% of the total, according to NanoMarkets.
The report does see SiTFPV's hold on sector supremacy slipping toward the latter part of its forecast period (2013-2016ish), as CdTe and especially CIGS come on stronger and even OPV gets into the fray.
Yet the silicon TF numbers projected are not exactly chopped liver. The NanoMarketeers think that next-gen SiTFPV--triple-junction cells, consisting of materials cocktails of amorphous, micro- and nanocrystalline layers, with Si quantum dots and nanowires also in play--will help keep the ball rolling, the conversion efficiencies growing, and the cost per manufactured watt dropping.
Here's what NanoMarkets believes needs to happen for SiTFPV to keep its mojo working into the next decade.
"Ultimately, the keys for amorphous silicon to maintain its dominant position in the TFPV marketplace and to grow in the PV marketplace in general are to increase the efficiency of the cells and lower the cost of materials. Areas where efficiency gains can be made are through further optimization of the tandem-junction thin-film deposition, which in the short term translates into further optimization of the microcrystalline bottom absorber followed by a transition to a nanocrystalline bottom absorber.
"The second possible efficiency improvement from a materials point of view is modification of the current processes used to texturize the TCO, which will improve the light-trapping efficiency and thus overall efficiency of the cell. The longer-term materials challenge is to transition either to a silicon nanowire or silicon-based quantum dot absorber, which if successful will provide a path to efficiencies above 15% while using most of the existing manufacturing infrastructure."
"The other half of the equation is aggressive cost reduction. A significant cost reduction can be realized by higher levels of integration to the process flow. For example, the TCO can be integrated as an inline process instead of a separate operation as is typically done today. Silane utilization and overall gas usage reductions are also areas where optimization and process improvements will result in cost reduction. Many of the other traditional fab metrics such as higher throughput, yield and uptime can leverage learning from the semiconductor industry and will also help, but these are second-tier improvements."
So how much will SITFPV grow over the next octuplet of solar cycles? Total production should exceed 1 GW next year, 2 GW in 2012, 3 GW in 2013, then just continue flying north in gigawatt chunks for the rest of the period, if the research outfit's prognostications prove premonitional. On the revenues side, the "middle-of-the-road scenario" forecast calls for $1.3 billion this year, over $2.1 billion in 2011, and then just keep adding a billion or so per year for the duration.
As for a-Si PV materials, the company believes the total market will top $1.14 billion in 2011 (led by the active material category), almost touch $2.3 billion in 2014, and crest $3.2 billion in 2016.
Although I am skeptical of forecasters in the solar PV space in general (can you say, "maddening inconsistency," "flawed data," or "hidden agendas"?), attempts to project beyond the next few years strain credulity. The kind of crystal-ball accuracy required to nail the numbers five or more years out is about as common as a monocrystalline cell with 30% efficiency--basically beyond the theoretical limit.
That being said, I do find NanoMarkets' growth forecast presents an interesting crossover point toward the mid-2010s. At some point in 2015-2016, the production numbers will come to parity--$1 million in revenues for every 1 MW produced--and then slip for the first time to the sub-million-dollar-per-megawatt zone, according to the firm's model.
Still, it's a bit premature to ditch the old saying, "a megawatt made is a million earned."
