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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.
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.
1.6 is very high. A more practical estimate is between 800W and 1.2kW.
It did mention efficiency, so you can calculate it. Find an insolation map, find your location on it, find the average kWh/day you get, and multiply by the 11-13% figure mentioned in the article.
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
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
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
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.
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Rent solar power for your home and save: http://mdsolar.blogspot.com/2007/01/slashdot-users-selling-solar.html
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