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Method for $1/Watt Solar Panels Will Soon See Commercial Use
An anonymous reader writes "A method developed at Colorado State University for crafting solar panels has been developed to the point where they are nearly ready for mass production. Professor W.S. Sampath's technique has resulted in a low-cost, high-efficiency process for creating the panels, which will soon be fabricated by a commercial interest. 'Produced at less than $1 per watt, the panels will dramatically reduce the cost of generating solar electricity and could power homes and businesses around the globe with clean energy for roughly the same cost as traditionally generated electricity. Sampath has developed a continuous, automated manufacturing process for solar panels using glass coating with a cadmium telluride thin film instead of the standard high-cost crystalline silicon. Because the process produces high efficiency devices (ranging from 11% to 13%) at a very high rate and yield, it can be done much more cheaply than with existing technologies.'"
Could some one show me that the cadmium used in the photovoltaic has little or no environmental impact please?
You don't need to worry about the environmental impact of cadmium, but rather the environmental impact of cadmium versus the environmental impact of current energy production from fossil fuels, etc.
Seven puppies were harmed during the making of this post.
Unless they have no alternative to home-generated electricity, the cost of alternative generation systems is an uneconomic solution for most people.
I too live off-grid, in a small observatory at the top of a high mountain. Even though the cost of AC mains to the site was well-beyond my means, the only reason I could afford to generate my own electricity was because I work in the electrical industry and got the batteries, heavy cable, components for regulators and inverters, etc, for free.
The only things I had to pay for was the PV array and that was not a trivial expense, at $10 per-watt, excluding taxes and shipping.
My off-grid system works very well, but it requires a lot of on-going TLC, far more than most people I know could be bothered with providing. They want systems they don't have to think about and which "just work". Few have the self-discipline and willpower required to minimise their loads, letalone perform regular maintenance checks.
I've always been a Renewable Energy geek, but if I could have got an affordable AC mains connection to my site, I would have one. As much as I love playing with windgens and solar setups, with a wife and two kids now, I simply don't have as much free time on my hands as I used to.
Exactly! $1 a watt panels are darn expensive if they only last 5 years.
I run on 20 year old Solar panels here. I buy only used and discarded from solar plants out west and they look brown from the years of solar exposure but cost me far FAR less than buying new so I can afford more watts for the money. Decent used one approach $2.00 a watt but that is at higher voltages. and my panels will last another 30 years easily with care.
Do not look at laser with remaining good eye.
Here in Taiwan, we just had the annual solar trade show which is becoming a really big deal on the silicon island. Solar has become a huge because it dovetails right in with other semi industry players that get put together in industrial parks.
So this year there was a big dollar-per-watt announcement from Oerlikon. If you don't know who they are, they're a Swiss provider of turn-key thin film or amorphous silicon solar panel factories. They've got several partners in Taiwan already including, most recently, some of the large-scale optical media manufacturers who already use similar techniques and equipment and have some cash to invest.
The local Oerlikon rep was saying that producers will be at sixty cents per watt within forty eight months and that this will mean actual product at the dollar a watt level. Hey, I'm just passing along what the sales rep said. Obviously he's got a reason to overstate his case, but that's what he claimed was coming down the piple.
I think it's also worth noting that a former Slashdot sweetheart that went by the name of Spheral Solar has basically dropped off the map because they realized that amorphous silicon was going to take over.
Oerlikon bought up Excimer laser of the UK last year. One of the repeated steps in doing thin film solar is laser etching.
I'm not too sure about the tech being referred to in this piece, but dollar-a-watt PV, which is what the UN and other agencies have said is the tilting point where solar is cheaper than coal or natural gas, is already being spoken of at industry trade shows and shouldn't be seen as a wildly implausible announcement.
OK, let's see if this is for real.
First, the "story" is a regurgitated press release. For an more critical story by a local reporter, see "AVA Solar enters crowded field", by Tom Hacker.
The AVA Solar web site has almost no useful information. But they have a patent on the manufacturing process, which discloses what they're trying to do. Among other things, the patent tells us that "AVA" stands for "Air-Vacuum-Air". The process is mostly conducted in a low grade vacuum, with some preprocessing in air before the vacuum chamber and some final steps after vacuum processing. The big deal is supposed to be that there's only one trip in and out of vacuum, which simplifies the production process. This patent was filed in 2000, so they've been working on this for a while now.
They're trying to make cadmium-telluride solar cells, which aren't new. The new thing is making them with a continuous process, instead of in batches.
AVA Solar has some job ads on Dice. They're looking for a plant manager, and on Dice they say "200+" employees, rather than the "500+" mentioned in the press release. AVA Solar doesn't seem to actually make anything yet, so they have to build and run a new kind of manufacturing plant of their own design without an organization experienced in doing that. That's hard.
They're supposedly building a pilot plant, to be running by the end of 2007. So wait a few months. If that works, it's worth looking at them again.
Lets see. Assume the competing cost is at present 10 to 25 cents per KW-hour. We'll use the upper end because future power prices will rise whereas the Solar panel is a fixed cost.
So let's see the solar panels are 100000 cents per KiloWatt. if the last 4000 then that's breakeven. We'll assume that the power is available 10 hours per day. That's not realistic for individual use but perhaps with batteries, and selling back to the grid this could be done. So 4000 hours is 400 days. Or about 1 year. Not too bad.
Now that ignores the efficiency of either pushing back to the grid or battery storage. Let's assume 50% loss. Then this is 2 years to payback on the cells. But now we also have to payback on the batteries. Let's assume the batteries needed const aout the same as the solar cells. That would double this payback to 4 years.
Finally this is assuming capital is free. Assume one borrows at 8 % interest. Then this another 5 months to payback.
So the whole operation needs to run undegraded for 4 to 4.5 years I estimate for break even.
That figure could be cut in half if one could sell back to the grid rather than batteries. ( Fine--as long as there is a grid and every one does not do that!. )
If the cells were down to 50% effiency after 4 years then this extends out to ~7 years to payback. If one cannot get that watt for the full ten hours then this gets even longer.
It sounds to me, roughly speaking that at 1 dollar per what things are in the ballpark for breakeven.
Some drink at the fountain of knowledge. Others just gargle.
I would like to use other cheap thin film photovoltaics like amorphous silicon, CIGS or polymer based instead of the CdTe PV. I handle cadmium a lot in my work, to me, the environmental impact of cadmium versus the environmental impact of current energy production from fossil fuels is like plastic bag or paper bag. Both of them are not the solution.
There is a spark in every single flame bait point.
with conventional solar pannels the cost per watt is around $3-$5. so the $1 per watt price isnt that impressive, what is impressive is the scale at which they can produce these new panels... they could sell self install kits at wal-mart and still have no problem with inventory..
conventional panels have always been restricted by the amount of pure silicon that can be produced, and with microprocessors using the same pure silicon its been tough for solar panel makers to have enough supply to meet demand. in fact the major tech companies have multi year contracts on 99% of the pure silicon being produced world wide.
btw this technology does not cheapen solar power to utility electric rates.. according to a website about solar energy Around 59% of world solar product sales installed the last five years were in applications that are tied to the electricity grid. Solar Energy prices in these applications are 5-20 times more expensive than the cheapest source of conventional electricity generation, although they may only be 3-5 times the electricity tariff that utility customers pay. By contrast, PV can be fully cost competitive on economic grounds in remote (off-grid) industrial and habitational applications.http://www.solarbuzz.com/StatsCosts.htm
so cutting the solar panel cost to 1/2 of what it was before makes solar a preffered method of off-grid electrical applications, and brings the total consumer cost down to levels (15cents/kwh) that they would actually pay for electricity. still not ideal, if they can bring the cost down further with economies of scale, then this will start a revolution for earth-friendly consumers who will be able to take out a loan to buy a $10k system that cuts their electric bill by 25% (to fully power a house with typical energy usage would run about $40k with these pannels, or $80k with normal solar pannels) which means the pannels would have to last at least 34 years to recoup the cost invested in installing a solar system. (theyd have to last for 68 years with normal solar panels) now if youre using a grid+solar setup you can probablly keep using those solar panels as long as theyll crank out energy, but of course they do degrade over the years, producing less energy... and widespead solar power adoption will cause winter energy spikes, but if they have to have coal fired plants that they only run 3 months a year, because of widespread solar adoption... well itll be an improvement.
$1 per watt is frankly about 10 times more expensive than we need to get solar energy for solar electric companies to adopt the technology without government subsudies/regulation.
this is why companies like excell energy are turing to wind turbines to meet the 20% renewable energy production mandate minnesota has put them under by 2020.. wind turbines are ALREADY produced around the COST per kwh of coal fired plants. (theyre sold for more obviously though)
wind energy is a natural byproduct of solar energy, and with the new tidal stream generators it is possible that the uk and scottland could see more than 10% of their total electrical consumption produced entirely from rapidly moving undersea currents.
tidal projects obviously have less problems with home owners that wind farms, and since areas with high tidal streams tend to be far from good scuba diving sites there should be little complaint about installing tidal stream generators.. in the handful of places where they are genuinely viable.
its nice to know that more californians will be able to afford a basic solar install, but this isnt something so revolutionary that were going to stop building coal fired plants because of it.
https://www.gnu.org/philosophy/free-sw.html
A 2 foot by 2 foot chunk of window glass in the store is $17.40 at Rona. A square meter is 10.76 square feet. So a 1 meter square piece of glass would cost $46.82 at these rates.
Even the cheapest solar cell should be expected to cost more than plain glass since it includes at a minimum plain glass.
Next.
Solar constant is 1300 watts per square meter in space and max 1000 on the surface of the earth.
One can expect on average 12 hours of darkness. Then we can expect only 50% of this max because most of the time its not high noon. One actually has to integrate the sin curve.
So we can say 12 hours at 500 watts average maximum collection and at best we can hope for about 50% of this. This 50% discount takes into account rainy days and snow blowing on it and maybe it gets a little dirty because people don't wash it often enough.... there are lots of things that can go wrong here. So I pick 50% out of the air as a practical fudge factor to convert to what is theoretically possible to what one might expect.
This is 3000 watt hours per day falling on the panel in a useful way, and the efficiency of the panel is say 10-13% so I'll use 10%. We can expect to get say 300 watt hours per day per square meter. This is 0.3 kwh which in worth say about 3 cents at a rate of 10 cents per kwh. This is still 25 watts per square meter for 12 hours and this is what a mini florescent draws.
But from the article - they say $1 per watt so I assume they mean per watt peak capacity.
This would be 100 watts per square meter since we have 10% of 1000 and the 1000 is peak. The duty cycle is at best 1/4 of this. Nevertheless, $1 per watt * 100 watts is $100 per square meter.
Thing is $100 per square meter is only 2x the cost of a plain glass windowpane so its actually unreasonable to expect they will be able to sell these panels at anywhere near 2x the cost of plain glass. A complete window assembly is in the order of a few $100 bux. Maybe we get the complete panel retailing at $200.
What should we expect to really get out of a $200 panel in terms of energy?
At best, 25% of max and this is about 25 watts per square meter and this is over 12 hours. Hence one should expect the thing to capture at most say 300 watt hours per day.
As I calculated before this is about 0.3 kwh = 3 cents worth of power. $0.03 * 365 = $10.90
Invest say $200 in a panel when it retails and get $10 per year from it in electricity. This is a 20 year pay back not counting installation, maintenance, and so forth. At a 5% interest rate (cost of capital) it has a ZERO Return on Investment (ROI).
Now the real issue. Suppose everyone does this. It will have the effect of destabilizing the grid because it puts the power company in the position of standing by ready to supply energy at night and when the sun doesn't shine but meanwhile when the sun is shinning their expensive infrastructure sits idle. So long before this gets deployed the rules get rewritten.
The thing is that we can already capture solar energy passively and build houses that will save way more than $1000 per year in energy and do this for a capital investment of less than $5,000. All we need to do is put R50 and R70 in the walls and ceilings. We can do a LOT more than this. To capture say $1000 per year with say these high efficiency panels will cost 100x$200 bux = $20,000 of capital and this does not include the control systems.