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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.'"
actualy, a 20x20 foot aray with good batterys and inverters will power a home with a family of four quite nicely. (I myself lived in a house that was totaly off the grid for about 5 years, pure sunlight on a 20x20 grid in the summer, minor supliment by propane generator in the winter months)
I've decided to Diversify my Holdings. I've divided my cash between my left and right pockets, instead of all in one.
The article doesn't mention how many watts per square meter this panel will produce. The cost of the panel is important, but so is the cost of the land required and the return of your investment.
Washington bullets will simply be known as the "Bulle
Well, 1 kilowatt for an hour costs me 25 cents (thereabouts). To make a kilowatt, I would need to spend $1,000 on these. That means that they would have to operate for 4,000 hours for me to make my money back (well, 4,000 hours of electric usage).
Basically, it looks like, if they last a couple years, they would pay for themselves (166 days of full utilization, but that's not going to happen in the real world). Not bad. If they're durable (and last 5-10 years), they could really cut down on electric costs.
Oh, plus the whole saving the planet from destruction thing. I guess that might have some value.
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.
One square meter of land on a bright sunny day will get appx 1.6kW of light in an hour. Assuming 11-13% efficiency as mentioned in the article, you'd get just a little over 160 watts per square meter per hour.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
There are several houses on my area in Northern California that have photovoltaic installations that produce more electricity than the homes consume. The excess goes to the power company for a credit against future use. These are homes with air conditioning and people that don't live austere lives. Their installations cover less than the entire south facing slope of a conventional roof. The problem is that they wouldn't come close to paying off without big fat gumnt subsidies. At $2.00/Watt they would be economically feasible without subsidies.
Assume the panels are 1/2 the cost of the system so the total system costs $4/Watt, or $8,000 for a 2 kW system. Assuming 6 hours a day generation, that's 4380 kW-hrs a year, or at $0.10 kW/hr that's $438 worth of electricity. 438/8000 = 5.4% tax free return on investment. If you live in the US with a decent income, you would have to earn over $700 to have $438 for your power bill after taxes.
If you don't like my numbers feel free to substitute your own.
The real question here is how will these panels stack up to current poly panels with regards to their life span? All solar panels degrade over time - that is, produce less power as they get older. Rule of thumb for a poly panel is around 25 years. While there are many types of panels only a few are actually in mass production and have the required life spans. If you are looking to install solar now, polycrystalline panels are what you want to get.
:-)
1.5 to 2 KW worth of panels is enough to run a typical house unless you have a machine room. Even if you use more power then your panels can produce, it's actually all to the good because it means the panels are recovering the highest-tier electricity costs for you, dropping you down to a lower tier with your utility company.
You don't want batteries unless you are off-grid, and most people will be on-grid. There are many grid-tie solutions available and costs have come down considerably over the years. Batteries are of course essential if you are off-grid but knowing the many hackers here I'm sure many of you would like to be able to disconnect from the utility completely, survive blackouts, and so forth... but generally speaking, the batteries and equipment required to do that adds a lot to the cost of the system and involve considerably more maintenance and worry.
A straight grid-tie system is completely maintenance free. I literally have not had to touch my system since the day it was installed. I just pop into the garage and stare at the cumulative power display every so often
http://apollo.backplane.com/Solar/
-Matt
A 2003 study on French dietary intake showed an average intake of 3.6 micrograms cadmium per day. Multiply that by the us population of around 300 million, and the US population should be able to safely consume at least 9 grams of cadmium per day. Multiply that by 365 days a year, and we (as a nation) should be able to ingest at least 3.2 kilograms over the course of the year.
Therefore, the solution to the cadium waste is obvious. Put it in the water. After all, dilution is the solution to pollution.
Damn_registrars has no butt-hole. Damn_registrars has no use for a butt-hole.
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.
The solar constant is about 1300 watts per square meter (in space). On earth the best you can hope for is about 1000 watts peak. So on average we will look at about say 50% of 50% and less on a cold winter day when we need both heating and more lighting. In fact on a winer day at about 51 degrees latitude we get about 8 hours of light and even then its less than 250 watts per square meter.
If we take 10% of 250 we get 25 watts. This is about as much as a high efficiency mini florescent uses.
To run a toaster we will need 40 square meters of solar panel and to roast a turkey and cook on top of the stove as well we look at 40 amps @ 240 volts (check your main panel folks) which is about 385 square meters at 25 watts per square meter.
Thing is that we might want to roast the xmas turkey after dusk, so we better plan on batteries.
A deep cycle 12 volt battery (lead acid) can be expected to hold 60 amp-hours.... at least this is what the Hawker batteries I use for my UPS system are rated for.
12*60 = 720 watts hours. To roast the turkey say takes 4 hours at a draw of say 30% of 40 * 240 which is about 11,250 watt hours. So we need 15 batteries for this. Next if we draw them down any more than about 20% the number of cycles goes into the toilet so we'll need about 5x as many so we can draw each to about 20% of their max rating. We'll need 75 batteries.
New these batteries cost more than $250 bux so that is a battery investment of $18,750.
Clearly one will not be running an electric range off that solar system.
I'm not scoffing at the idea. I think its good but one has to find a way to store that energy and perhaps the best use of it will be to create hydrogen.
The thing is that sure it can feed into the grid during the day. All this does is put idle the current generating infrastructure and we still need that infrastructure for night operation. Of course it would save the fuel needed to operate the plant.
But then what would we use the existing generating stations for when they are idle? Generating hydrogen?
Somehow it doesn't make sense to burn fuel to create electricity to make hydrogen when we can simply for instance chemically take the Methane apart and get hydrogen that way.
One really has to think about how this cheap solar technology fits into the full cycle of energy needs.
Nevertheless I think it is good and maybe we should use it to pump water up hill. Then at night we can let the water flow back through the pump and turn it into a motor-generator. Batteries are just one way to store energy. It can be stored as compressed air, water at the top of a hill, chemically such as hydrogen gas... but it will need to be stored and in great quantities if this technology is going to go anywhere.
Plants such as trees are another good solar collector. We tend not to use them. They are reasonably efficient and serve as their own battery system because if you need more heat you can chuck another log on the fire. Since most of us tend not to use the solar collectors mother nature already created for us, I suspect that there will be huge issues to overcome in order to deploy even cheap man-made ones.
Now here is another thought. The best efficiency of these collectors is say 10%. If we capture the same energy for space heating our houses we can easily get over 80%. Yet, most of us do not even do this.
A super heated house with R70 in the ceiling and R50 in the walls costs about $1 dollar per square foot of building envelope extra during construction. This will eliminate the vast majority of summer cooling and winter heating loads. Here in Calgary for instance a house like this does not need a furnace and we can have winter days that are 40 below for weeks on end. A house like this can get by with a nice fireplace and wood heat and will burn less than 1 cord of wood per year. That wood costs about $100 dollars.
But, most of us don't even do this.
I think solar is a great idea but a low
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.
Note that it's very hard to be green with an off-grid system. Off-grid systems tend to use batteries, and for proper operation you don't want to discharge the batteries too deep, and so quite often you overprovision your cells and you end up throwing away the energy from the cells into mostly full batteries a lot of the time. You can try to live greener (more efficient appliances etc.) and that's almost a must off-grid, but the off grid electricity itself is very expensive.
On grid, every watt generated by the panels goes somewhere and does something, because you feed it back to the grid, where it reduces the demand for fuel-burning electricity.
So living off the grid can be rewarding for those who want to be very non-urban, but it should not be confused with being green, energy wise.
Has it been over a year since you last donated to the Electronic Frontier Foundation
Be careful here. In California, which is where I live too, it doesn't get dreadfully hot like it does in the midwest, or at least not for more then a few days a year usually. A solar array of the size normally needed to reach net-zero with the power company doesn't even come close to being able to generate the power needed to run even small whole-home air conditioning systems. As long as the AC is only used a few days out of the year (which is typical in California), then you can still reach net-zero over the whole year. But in somewhere like Texas you wouldn't have a chance. AC is usually not in the cards if you are trying to achieve energy independence.
-Matt
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.
According to this article, they expect the things to last about twenty years, but they're still running stress tests. Same program, but a little over a year ago.
You want the truthiness? You can't handle the truthiness!
FirstSolar uses CdTe http://www.firstsolar.com/environment_cdte.php and the durability of the panels remains an issue, but one they are addressing. Their aim is to demonstrate 20 year performance above 80% of the initial efficiency. The trick is to do this in less time than 20 years and they are getting help from NREL to pull this off. Their cost of production is $1.19/Watt and headed down.
--
Rent solar power for your home and save: http://mdsolar.blogspot.com/2007/01/slashdot-users-selling-solar.html
Yes.
And after they place the condemnation notice on your front door, they'll kick your dog.
Seriously, what makes you think that the engineers building this thing are so incompetent that they haven't considered the possibility of hail falling on your roof? They actually do run tests like that. Second to last paragraph here.
I also find it very interesting that you didn't mention the dangers of actually living in a poison-dusted home, but only the danger that the EPA might deny you your God-given right to live in said death trap.
Tell you what, when serious people who actually know about the toxicity and regulatory requirements of cadmium telluride start telling me that this solar technology may present problems, then maybe I'll start worrying.
You want the truthiness? You can't handle the truthiness!
Well, if exposure to the sun is going to cause them to deteriorate and turn brown, you should probably try to install them in a shady location to prolong their life.
Depending on the investment in the solar panels, I might even consider setting up some sort of permanent awning to protect them from the sun at all times - protecting my investment as it were.
I would mod you up for that if I could. I try to not think about places that require AC at night
FWIW, this area has around 30 days over 100 per year. Nights are usually comfortable and the daytime humidity is low.
Shit, durring the summer in TX we're lucky if it gets below 90 at any point durring the night. Last night around 3am it got down to 87, and the AC was off for more than 15 min. AC units pretty much run 24/7 may-october here and a $350 july or august electric bill isn't at all uncommon ($.11-.13 per kw/hr here in Dallas). Temps typically only fluctuate 8-10 degrees between highs and lows here. I think solar would be a great argument here durring the summer...
moox. for a new generation.
If you want to correct people, you should check your facts first. I was referring to deep cycle batteries. They are called that because they can do far more deep cycling than typical car batteries, but in fact if you research it you will find that the deeper you discharge them the shorter their lifespan. Generally you want to design your system to not go below half in ordinary use, and drop down from time to time in peak use.
However, that's actually not relevant to the main issue. You don't want to live close to the edge. You want to be sure you have capacity for when you need it. But you also want your batteries returned close to full by the end of the day to provide your power needs that night and into the next run of cloudy days. So you have to provide enough solar wattage to make sure you do that most, if not all days. Or you need to have an alternate power source for peaks (like a generator.) But most solar people don't want to use a generator.
Anyway, point is on the many days when you use less than capacity and the batteries are fully charged, you are just throwing away the power when the batteries are full. That's not the green thing to do. Certainly the people who go off-grid on a property connected to the grid are being foolishly non-green. The grid provides both a way to get any excess power you need during low solar periods, and a way to make sure all the power you generate goes to good use. That's why government rebates etc. only apply to grid-tie solar installations.
Has it been over a year since you last donated to the Electronic Frontier Foundation
But an awning can only offer so much protection ... really the only surefire way to protect your solar panels from sunlight-induced degradation is to install them in some kind of underground environment where they are completely isolated from the environments.
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.
You guys are amateurs. I have installed my solar panels in an underground cave with a sealed access point along with my wind turbines. My solar panels never deteriorate due to solar degradation and my turbines never suffer the terrible wear and tear that is caused by constant motion. I figure that they should last 10x as long as an irresponsibly deployed solar/turbine array, which means I'll get 10x the return on my investment!
I hate printers.
wow, I was reading this thread and was utterly shocked at how people could get things so backwards. solar panels were meant to be used - degradation is inevitable. There is no need to protect them from the environment; you need to expose them to more environment. With only 11% efficiency you need as much light energy as possible to capture. That is why I poor kerosene on mine and light them ablaze. With all that direct light from the fire, I get unbelievable amounts of power before the unit dies.
When all else fails, try.