New Solar Panel Technology Gaining Momentum 181
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."
Re:Silicon shortage? (Score:4, Informative)
There is more info at
Indium shortage? (Score:4, Informative)
From Wikipedia: [wikipedia.org]
Iam not sure about where Wiki got the figure from though.
Cheaper high-purity silicon (Score:1, Informative)
International Herald Tribune: Norway's Orkla group to build new plant to produce high-purity silicon for solar cells [iht.com]
Aftenposten: Orkla goes solar [aftenposten.no]
Re:bad units (Score:4, Informative)
Re:Silicon shortage? (Score:3, Informative)
And that's the crux of the problem too. Silica (SiO2) is abundant (quartz sand), but SiO2 is a BITCH to break apart (the usual reaction is with carbon in an almost 2000 deg C arc furnace), you have to partially melt it or transform it into gaseous silanes (e.g., HSiCl3) to remove impurities, and then you have to grow the Si crystals in high temperature furnaces in very clean conditions. Some of the impurities have to be reduced to the parts per billion range for some applications. It is an energy-intensive and expensive process, and the demand for Si for computer chips cuts into supply for solar cells.
Here's some info on making polycrystalline silicon [sumitomo-ti.co.jp], and wafer production, including crystal growth [tocera.co.jp]. All of that happens before the solar cells or chips get made.
If we lived on a planet without any oxygen, maybe it would be easier
Unlikely in the short term (Score:3, Informative)
Solar panels need optical transparency in their protective layer. Keeping roads clean enough to provide that level of optical clarity is just not going to be workable, except possible with nanotechnology.
When we get self rebuilding roadbeds then solar roadbeds might be practical, but for now roofs are much more practical as targets - most are slanted, don't have cars running over them, and get rained on periodically to help with self cleaning.
Cost vs Efficiency (Score:3, Informative)
I'll argue that for a typical small house (1500 sq-Ft) there is more than enough roof area to generate all the electricity for the house, even with 6-7% efficient solar panels. Unfortunately, buying current solar panels, this much energy would cost you >$35,000 !! (And that doesn't include batteries, tracker, inverter.... etc)
If these guys can make lower efficiency panels that also have lower cost/Watt, it is a winning situation for everyone. Where do I buy their stock ?
$1.37 and sub $1 a watt panels (Score:1, Informative)
The only 'problem' is the back-end electronics are still "expensive" and will remain so, even if panels drop from the present price of $5+ per watt to $1. The panels will just be the cheapest part in such a system. Now, if you were powering, oh say, 48 VDC or 12VDC computers, the interface electronics could be as simple as a diode.
Re:Cost vs Efficiency (Score:1, Informative)
the sun at various points will also affect the energy per square metre. A full analysis would involve latitude, pitch angle, etc., but let's assume
that the roof area and sun angle is such that it is perfect all day. At 6% efficiency it might generate 4kW. This would be enough to run the peak
demand of an air conditioning unit in a house in a warm part of the USA if the house was not well insulated. This is with the entire roof covered in
panels, which would be very expensive. So at 6% efficiency it doesn't look to be a good bet. At 20% efficiency then you'd be generating more like
12kW, which is respectable, except that your roof/weather/orientation/latitude would be such that you would not achieve this over the whole day and
every day.
So the first measures should be effective insulation (walls and ceiling) and energy efficient appliances and systems. The $ return per $ spent
is better.
Having done this it is then worth looking at what residual power needs you have. If you need hot water than you'd be better off with
solar thermal on part of the roof as the efficiency is higher, and a well insulated hot water tank is a very cheap way of storing energy. If you
are almost never in during the day then PV panels might not make sense as they would be generating power when you are elsewhere, unless you either
have a storage mechanism, or you are exporting your power to a grid or microgrid. If you live in a windy area then for windy winter nights then
a roof-mounted wind generator might be appropriate.
On the other hand if you are retired and home most of the day but go to bed early then on top of the solar thermal PV panels might make sense.
It all depends. There's a good case for microgeneration of electricity on offices, malls, etc., that are in use during daylight hours, possibly
more so than solar thermal as you'd never use all that hot water. For a health spa, though, solar thermal to warm that swimming pool would be
ideal.
It's all about appropriate measures, but almost always the first measures need to be energy efficiency - insulate, and reduce power usage in
appliances (e.g. fridges, which are improving dramatically, and LCD TVs which now use about half the power compared to an equivalent screen
size CRT).
There are other promising techniques. (Score:3, Informative)
If this keeps up, we'll probably have a choice from a whole range of efficiencies, and more importand $/watt.
There already are [oksolar.com] companies out there that sell solar shingles. They're not economical yet for most applications, but it's starting to come.
Re:Silicon shortage? (Score:5, Informative)
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.
Miasole (Score:4, Informative)
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.