The Good Stuff
It's encouraging to see that this nano-tech stuff that I write about
is actually becoming real.
This is a pretty big story, and
It increases World Wide PV production by 30% or so.
Nanosolar to build world's largest solar cell factory
21 June 2006
Nanosolar, a Silicon Valley start-up founded in 2001 to commercialize low-cost solar cells, has won $100 m in funding to build a manufacturing facility in the San Francisco Bay area that will produce 200 million solar cells per year. The plant will have a maximum output of 430 MW per year, almost triple the existing solar production capacity in the US, and is due to start production in 2007.
Nanosolar will also establish an assembly plant, most likely near Berlin, Germany, that will produce more than one million solar panels per year.
Nanosolar's technology exploits thin films of copper indium gallium diselenide (CIGS), a direct bandgap semiconductor that generates a much larger photoelectric effect than silicon per unit of material. As a result, a thin film of CIGS just 1 µm thick can generate as much electricity as a 200-300 µm thick crystalline silicon wafer.
Thin-film CIGS solar cells therefore offer similar conversion efficiencies to those based on silicon, at around 20%, but can be manufactured much more cheaply. Indeed, the company claims that a silicon solar-cell factory of the same capacity would cost more than one billion dollars to build.
Nanosolar isn't alone in developing a lower cost alternative to silicon solar cells, which currently account for 90% of the global photovoltaic market. Fellow US start-up Miasolé is also producing CIGS solar cells, while other companies - notably Solarion and Würth Solar of Germany - are exploiting copper-indium selenide (CIS), a related material that also offers good conversion efficiencies.
Still others are focusing on dye-sensitized solar cells, which exploit photoexcitation of organic dye molecules to generate a current in a semiconductor layer made of titanium oxide nanoparticles.
Against this competition, Nanosolar is the first to achieve an end-to-end manufacturing process that can be scaled to high production volumes. Most importantly, the company has exploited molecular self-assembly to produce an "ink" of CIGS nanoparticles, which can then be printed onto a flexible substrate.
According to Nanosolar, this printing process is more efficient and repeatable than alternative vacuum-coating techniques - which struggle to deposit the CIGS compound with the correct atomic structure to achieve good efficiency - and enable the use of substrates that are up to ten times cheaper that the stainless steel substrates needed for vacuum deposition.
Nanosolar's flexible substrate technology also allows solar-cell modules to be assembled with high throughput and high yield."
There are others too.
We just need to focus on the good stuff.
With advanced wind turbines
and advanced solar cells,
and advanced ultracapacitors,
and a movement to hydrogen for our power plants,
We can all stop smoking,
At least the bad stuff, that is.
picture from Mongabay and Solargenics