A new kind of cell?

[inode buddha]

Story here, courtesy of slashdot:

http://science.slashdot.org/article.pl?sid=05/03/28/2320211&tid=126&tid=14

Seems like some company, DaystarTech, has a PV cell that uses a titanium foil instead of silicon.

And a random thought: cheap source of titanium being white paint (titanium dioxide pigment).

[Jeff7]

Titanium dioxide - fine and dandy, except that you want pure titanium. Titanium is very common in nature, but what makes it so expensive is that it is difficult to extract from the ore, because it's never found it its pure state.

Aluminum can also be difficult to extract. According to this site, "The process of making metallic aluminum is carried out in two successive stages: a chemical process to extract anhydrous aluminum oxide from the bauxite, and an electrolytic process to reduce the alumina to aluminum."

And you need a lot of electricity to get that aluminum.

Anyway, these cells sound interesting. The site lists an AM0 (?)efficiency of 15.2% - not exactly amazing, but still pretty darn good, especially if (and this is what we're all hoping for) the cells are at the same cost level, or lower than, regular silicon solar cells.

[scottsAI]

That's funny, I can't find a patent for daystar thin...

I wonder what's up?

[DanG]

Copper-indium-gallium-diselenide PV component on top of titanium foil - expensive unless you need to launch it into orbit or have it loiter at 80,000 feet... Just another exotic thin film PV for aerospace applications. The last manned moon mission found rocks w/ 15% titanium content, how about a robotic foundry process that could make solar "tent" collectors? Make ballooning structures that would stretch and support the pv array foil with only a shot of gas? Neat stuff, titanium

It would be neat to see 'terrestial' PV cells that didn't need hardening by cover-glass, perhaps a diamond film to cover the PV layers & that 15% efficiency would near 20% w/o cover glass losses. Ti sheet stock is commercially available in .3mm thickness - wonder what energy a skyscraper sheathed on the sunward side with this stuff would generate!

Just an aside: I wear a $90 watch with titanium case & band that is light as plastic, warm on the skin and the only marks on it are from having it in a pocket where it rubbed against itself. Got to reccomend titanium watches (unless you work around rotating machinery!)

[Reed]

Most state of the art thin film solar cells use stainless steel foil as a substrate. You can use molybdenum or aluminum as well. We are making solar amorphous silicon (a-Si) to make thin film solar cells on CP1 a conductive polymer thin film plastic that is only a few microns thick. The cells are only about 7% to 9% efficient but at 8% they deliver 2860 Watts of power for every kiliogram of weight (power density = 2860 W/kg)and you can roll them up like plastic wrap.

Titania is used sometime in organic cells based on plant phtosynthetic dyes that also make low power solar cells outside of the plant. These are based on PSI or PSII reaction centers from plant thylakoids. The other use of titania is in paint used as a beck reflector for solar cells.