Hybrid Monocrystalline and Multicrystalline Solar Cells

June 27th, 2011 by Nicholas Brown

"Solar crystals: A new solar panel from Suntech incorporates cells made using a new silicon-wafer casting process. The cells—the smaller squares inside the panel—are half monocrystalline (the dark areas of the cells) and half multicrystalline (the variegated areas)."

Suntech Power developed an efficient hybrid solar cell than can reduce the cost of solar power by 10% to 20%. As I mention sometimes in articles, remember not to confuse percentage with percentage points. 20% cheaper is 20% of the cost subtracted from the current cost.

Suntech is a Chinese company and these cells are 70% monocrystalline silicon and multicrystalline silicon is the other semiconductor. The new hybrid silicon wafers are half the cost of traditional monocrytalline wafers manufactured using the traditional method. Solar cell wafers are only a fraction of the cost of solar panels, so the overall cost reduction for solar power is actually 10-20%.

The idea underlying the manufacturing process was patented more than 20 years ago but it was never commercially developed by the patent holders.

Monocrystalline silicon (c-Si) solar cells are the most efficient type of solar cells commonly used today, and multicrystalline solar cells which are made from molten silicon and cooled to harden, are less expensive than monocrystalline, but less efficient as well.

The production process of monocrystalline solar cells is extremely expensive due to the fact that an enormous amount of energy is required to manufacture them. A consequence of this is that it takes a long time for them to generate as much electricity as was used to manufacture the older monocrystalline type (15 years maximum, but it is not normally this long, modern solar cells average a couple to a few years).

The importance of this is mainly dependent on the source of energy used to manufacture them. If the energy source is coal, then it is a considerable problem, but if the energy source of nuclear, then it is not very important. Another factor to consider is the energy source that the solar cells would replace.

How much pollutant and CO2 emissions they ameliorate is also dependent on how “dirty” the source of energy they are replacing is. Coal is a good energy source to replace. If they are replacing nuclear power plants, however, then it doesn’t really help emissions. Multicrystalline solar cells are manufactured by a less energy-intensive process involving melting silicon and then cooling it.

Suntech CEO Stuart Wenham says that production can be scaled up quickly because it is compatible with existing wafer processing factory machinery and he also expects the photovoltaic (solar cell) industry to adopt similar manufacturing methods in the next two years.

h/t Technology Review

About the Author

Nicholas Brown writes on CleanTechnica, Gas2, Kleef&Co, and Green Building Elements. He has a keen interest in physics-intensive topics such as electricity generation, refrigeration and air conditioning technology, energy storage, and geography. His website is: Kompulsa.com.

Anumakonda Jagadeesh

Good post. Everyday news appears that solar cell efficiency goes up. Gone were the days when people used to comment that,” The amount of Energy that goes into the production of the solar cells cannot be recovered in its life time”.

More over the material used in solar panels aluminium,glass etc., is all energy intensive.

Dr.A.Jagadeesh Nellore(AP),India
Wind Energy Expert
E-mail: anumakonda.jagadeesh@gmail.com
http://www.kompulsa.com/ Nicholas

Yes, I edited it to clarify that it is not usually that high and that is for monocrystalline, and multicrystalline is taking over. I also added that the new energy payback time. If you have any other questions or suggestions, feel free to ask.
- Anonymous
  
  Where do you get your “15 years maximum”? From way back in history?
  
  If so, what does that have to do with panel manufacturing today? Current energy payback for monocrystalline is two years.
Anonymous

Something I just ran across…

“During 2010, China’s PV industry grew at a breakneck pace based on strong demand. Production of PV cells reached 13 GW, surging 173 percent over 2009, according to statistics from PhotonInternational. However, in 2011 several main end markets including Germany, Spain and Italy reduced their subsidies to the sector, which, in turn, led to a decrease in market demand followed by a drop in price.

Prices for PV modules held steady at EUR1.50-2.00 (US$2.00-2.70) per watt last year, but then plunged in the beginning of 2011. The average price has now fallen below US$0.90 per watt, and downstream manufacturers are still pushing for further decreases, according to a survey by Energy Trend.

Industry players are expected to see fiercer competition this year, which will mainly be demonstrated by price cutting, said industry insiders. The trough in the pricing has given small- and mid-sized PV firms a fatal blow, and the latest data shows gross margins for those firms have recently dropped to less than 10 percent from nearly 20 percent. The reshuffle of the players in China’s PV sector is seen as inevitable.”

PV selling below US$0.90 per watt!

This is most outstanding. It suggests that we are close to $2/watt installed (5kW and larger arrays).

When we hit $2/watt installed we’re making electricity for less than a dime per kWh in sunny places. And after capital costs are recovered we’re making electricity for almost nothing per kWh for the next few decades.

A dime is cheaper than the ‘all in’ price of electricity from both nuclear and coal. With none of the problems both bring to the table.

http://www.renewableenergyworld.com/rea/news/article/2011/06/chinas-pv-industry-expected-to-enter-into-long-term-price-war
Anonymous

I’m joining the chorus crying “foul” on part of this piece.

“Research conducted by CrystalClear, a private company, has shown that it takes two years for a PV system with monocrystalline solar cells to make as much energy as was required to manufacture the entire PV system. Researchers also calculated the energy payback for polycrystalline cells and polycrystalline solar cells manufactured by the ribbon technique. The calculations estimated that it took 1.7 years for a polycrystalline system to reach this point and 1.5 years for modules made from ribbon polycrystalline PVs. A previous study showed that thin film modules, which require even less energy to produce, achieved energy payback in one year.”

Read more: http://www.motherearthnews.com/energy-matters/dispelling-the-myths-of-solar-electricity-energy-payback.aspx#ixzz1QbGyxhfz

It sounds like part of this article was copied from a nuclear energy shill site.
tibi stibi

like gnana says 15 years seems not right. how can i buy a solar panel for a price which is lower than 15 years of energy?
http://www.facebook.com/people/Robert-Bernal/100000532403856 Robert Bernal

Ya, ya, ya, China this and China that…
Our so called “leaders” need to be fired… everyone of them!
We need to enact Trade tariffs on all foreign goods (except the panels!), no resource wars, and spend ALL the money on research for RE and its storage. We can’t have dark inefficient panels, though… they emit too much infrared if used to power planetary civilizations (but still must be better than burning FF’s).

Imagine what a panel would look like if it was only as dark as the wavelengths it converted over… If it was, say, 35% eff, then it would appear 65% “light” in color, perhaps like a smoked mirror? And would not be hotter than the ground it sits on. These are the kinds of innovations we need before solar can continue its exponential climb into energy provider #1 (in about 35 years at present rate of growth).

We also have to spend these above noted senseless and wasteful monies on nothing but battery/supercapacitor tech (and their robotic mass manufacture). Batteries are the MOST efficient way to store energy, now it is up to us to DEMAND the research,,, hundreds of $billions! Otherwise we will fall victim to a PAST that is bent on fossil fueled depletion in an overheated world -:)
- Anonymous
  
  You might want to do a little reading and see how that “we’ll go it alone” stuff worked out for India.
  
  Then spend a little time an make a list of all the American companies which would fail as they are cut off from the world’s markets. Sharpen a few pencils, the list will be long.
  
  (You don’t think we can stop the inflow of other countries’ goods and not have them do the same to us, do you?)
http://ca.linkedin.com/in/gnanal Gnana

The figure of that it will take 15 years to generate the electricity used to make the Solar cell is a very high figure. Recent figures are like 1 to 2 years Energy Pay back. Please check the latest figures and update. Thinfim printing technique makes this energy requirement further less,