New Solar Panel Technology Gaining Momentum

jessiej writes, "Even though copper indium gallium selenide (CIGS), a newer type of solar panel, is less efficient than its silicon counterpart, millions are being invested in manufacturing. From the article: 'CIGS panels use far less raw material than silicon solar panels and the factories themselves cost less to build,' $25 million compared to $230 million in one example. These types of panels could even be made into a t-shirt logo."

Comments

I can see it now

[also-rr]

A debian logo on your shirt powering a small bewulf cluster of wearable computers computing Pi to many, many decimal places. What a talking point! How will the girls resist!

Re:I can see it now

[Anonymous Coward]

They won't need to resist, they would be busy with solar powered toys of their own...

Re:Silicon shortage?

[Zarniwoop_Editor]

It is. Unfortunatly, to build solar cells you need crystalline silicon. These crystals have to be carefully grown and are quite expensive to produce.

There is more info at ... http://www.howstuffworks.com/solar-cell.htm

Dangers of solar power

[edxwelch]

If you deploy too many solar panels in one place you could use up all the sunlight. This has already happened in nothern Scandinavia and during part of the winter they now are in total darkness.

Re:Dangers of solar power

[hey!]

If you deploy too many solar panels in one place you could use up all the sunlight. This has already happened in nothern Scandinavia and during part of the winter they now are in total darkness.

Silly. You're getting free electricity. Just set up a bunch of bright lights to replace the lost sunlight.

Re:Dangers of solar power

[ByteSlicer]

Just set up a bunch of bright lights to replace the lost sunlight.

Yeah. And if you point the lights at the panels, you won't need sunlight anymore!

Re:Silicon shortage?

[theshowmecanuck]

but SiO2 is a BITCH to break apart (the usual reaction is with carbon in an almost 2000 deg C arc furnace)

You are partially right... I worked on a project where we were testing a new arc furnace design for smelting silicon (it was a DC furnace as opposed to AC). Wearing one of my hats on that project I wrote a computer model program of the mass and energy balances that took place in the furnace.

My application of the physical chemistry and calculus have passed the haven't used it/lost it point, but if I remember some of the basic things correctly... basically yes it is a real bitch to actually split the silicon (Si) from the oxygen (however, silanes are not involved). It takes a tremendous amount of energy to do so. One of the reasons silica (SiO2) is so abundant is that it is so stable. Being so stable means that it is hard, thermodynamically and every other way, to break it apart. So while Silicon (Si) in the form of Crystaline Silica (SiO2, e.g. quartz, silica sand) is VERY abundant, Si on its own is VERY VERY rare. SiO2 is so much more stable than Si.

• Typically the furnace at its hottest point will be around 5000 degrees C (a carbon monoxide plasma forms there).
• The silicon metal at the furnace spout where it is tapped/poured from, is typically around 1400 - 1500 degrees C
• The reaction is SiO2 + 2C -> Si + 2CO
• The intermediate product includes SiO (silicon monoxide which only exists in gas phase at greater than 1400 degrees C) and SiC (silicon carbide).
• Most of the actual reaction steps forming the silicon (from silica) happen in gas phase at obviously very high temperature.
• The actual smelting process (chemically) is similar to smelting iron: reducing the base metal (removing the oxygen) using carbon as the reducing agent at very high temperatures. (Silicon higher than for iron.)
• There are no silanes involved as you describe in the initial smelting process from SiO2 to Si.
• With respect to the parent post about silanes: they are possibly created/used later if the silicon needs to be refined to semi conductor grade, but I don't know. I was not involved in this aspect of silicon refining, which is highly proprietary, and which I believe is (or was) protected by laws relating to national security).
• The greatest use of silicon is not in electronics. It is in the making of synthetic rubber. e.g. silicone
• Technically silicon is a metalloid... at room temp: non-conductive, 1200 - 1400 C, conductive, for example.
• When it cools, it forms a metallic silvery solid that is very brittle, similar to bituminous or anthracite (hard) coal... which makes sense as it is in the same family as carbon. If you hit it with a hammer it breaks or shatters.
• The main raw materials in smelting silicon are typically quartz, coal, and charcoal (and sometimes other more porous carbonaceous materials to improve gas permeability in the reaction bed. The coal and charcoal is for carbon content, not heat. The quartz needs to be quite pure... e.g. no or very very little iron etc in it (brown stains on quartz are typically from iron... not from wayward hikers.
• In most silicon furnaces the top of the furnace mix is exposed to atmosphere, and is so hot the carbon monoxide (CO) off gas burns to CO2, which is inert/non poisonous (CO is as flammable as methane, but it is so poisonous that it is not practically safe to do so). Granted the large volumes of inert CO2 created is bad, but better than highly poisonous CO.
• An interesting point is if you spill enough molten silicon onto a piece of iron/steel so that the iron starts to melt, the resulting reaction forming Ferro Silicon is so hot that it keeps reacting until one of the reactants is used up (e.g. until no more silicon or iron), or it hits enough of a heat sink to cool to solidification. We had a spill once that took out about 10 yards of the rail tracks some of our equipment rolled on, as well as some other pieces of steel equipment. All of which we needed to re-install or re-build in a couple of hours. Quite exciting, and a huge pain in the ass.

Miasole

[ScaredSilly]

I've seen the Miasole production facility and had a chat with the CEO and one of the engineers at the end of the summer. There're a few interesting things that TFA doesn't mention. First, Miasole claims the low $25M price tag for a 200MW factory because they build all of their equipment from scratch. When I was on the floor, they were building a single 25MW line which they turned on for testing last month. That cost them a grand total of $4M (in parts) to build. E.g. they've already done one, so the pricing is reasonably accurate. Subsequent lines will be cheaper. This will give them a huge cost advantage over other similar companies.

Secondly, their production process is cheaper not only because material costs are lower, but also because they use a "reel-to-reel" process in which the semiconductor material is deposited on a sheet of steel which unrolls into the line, and then rolls back up on a reel on the other side. The steel sheets can then be cut and woven into a vinyl enclosure which can be rolled out on your roof like regular roofing shingles. Cool stuff. (They're probably going to attack industrial markets first though...)

Third, the management team comes from the disk drive industry, and built the Seagate facility that is responsible for ~30% of the world's hard drives (could have the percentage slightly wrong, but is in the ballpark). Hard drives use a similar thin film deposition process, and they have built several other manufacturing systems based on thin film processes. This is why the are able to get such a low cost on their equipment: they have the contacts and expertise to build from scratch.

For the record, I have not talked with their competitors, so I don't know the whole story, but Miasole seems very well positioned, and their facility is certainly real.