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Solar Panels Reach $1 a Watt
ZosX writes "An article over at Popular Mechanics announces that, for the first time, solar cells have been manufactured for the much sought-after figure of $1/Watt. They also talk about a new study of the cost of the particular raw materials used in different manufacturing processes. The conclusion is that the company that just achieved the $1/W milestone, using cadmium telluride technology, may not prove to be the long-term winner capable of meeting demand when it rises into the terawatt range."
It does not take that long to put in the "grid" part. My system was wired (the part requiring an electrician) in a couple of hours. The large cost component besides the panels is the inverter for a DIY. The magical box converts the DC from the panels to a sync'ed grid AC. The DC from the panels is extracted in such a way as to maximize the power, by constantly adjusting the voltage of the panel output. Its a cool little box with all sorts of protection to make sure the power company and your line doesn't crackle.
I'm preparing to install solar on my roof. It isn't that hard. I've completed almost all of the paperwork for the CSI grant and local permits. Mounting the panels to the roof is simple as is figuring out which way to point them. The wiring is brain dead simple. I have a local electrician lined up to come out and hook it into the actual panel for me. Total cost for his time is about $300. I'm saving $10k by doing this myself! Total out the door cost is about $23,500 for 4.6 Kw.
This is something we are told about just about any mineral resource, and usually once it gets short, we manage to find a new resource, obviously this cant happen forever, but running out mightnt be an issue for a while. Also it means this technology isnt going to be cost effective for long using the current materials.
This sounds like the classic solar is not a renewable energy source tale because of the non-renewable materials in solar cells. You do realize that once the cells are built, that they continue to work until damaged or otherwise decommissioned, and that the nonrenewables are not consumed in the process? Also, there are alternative materials to use, and alternative places to mine what there is.
It is dangerous to be right when the government is wrong.
That may be true, but for TCO, we're talking set up costs vs. money saved over the expected life span of the panels. We put some up at work, enough to cover about 50 - 70% of our energy needs depending on the time of year. (we ran out of roof space to cover 100% of our energy needs) Now we viewed that as a sunk cost on the part of the business. Last year we all couldn't take anymore money home without getting bumped up into higher tax brackets. So we decided to reinvest the profits to help improve cash flow. Which it has. It freed up enough to hire a jr. developer.
Total time to ROI is about 7 - 9 years by the absolute numbers in terms of savings on our utility bills. But the extra developer allowed us to put a product on the market this quarter instead of late Q2 or even Q3 of this year. Already it is earning enough to cover 40% of his salary and should be profitable by the end of the year. The product could make enough by this time next year to pay for the solar panels. If not next year, certainly within 24 months. If the solar panels last us 15 years, we're looking at recovering a good long term ROI even figuring in the replacement of certain parts at least once during that period.
I would like to see more people putting these on their homes where it makes sense. Obviously places like Seattle aren't ideal candidates, but if you could turn every house and flat roof into a power producer instead of consumer. I'm sure the power companies don't want that. And I'm not sure if the current government would like that since it would empower people to take individual action to meet their energy needs instead of relying on the government. Even if every home/business just produced 20% of the power they used, it would reduce the load on the power grid by that much. And it would make life easier for places that are already having brown outs etc.. (California)
"The problem with socialism is eventually you run out of other people's money" - Thatcher.
Well as long as they're using rare earth metals, they will never become available. Their supply is much too limited.
Cadmium may not be that expensive, and not that super-rare (though calling the supply abundant would be a stretch), there is barely any tellurium supply.
From the wikipedia page :
Tellurium is extremely rare, one of the nine rarest metallic elements on Earth. It is in the same chemical family as oxygen, sulfur, selenium, and polonium (the chalcogens).
And the reality is ... of all the atoms in the universe (and "more or less" on earth) you have the following relation, for every ton of gold in existence (on earth), there's about 100 grams of Tellurium available.
It's not expensive, because no-one's using it. But if you start mass-producing anything with tellurium in it that cheapness will disappear sooner than you can say "exhausted supply".
It would probably be a very good investment to buy (right now) a ton or so of tellurium and put in your basement. Perhaps a bit unorthodox an investment, but before 20 years pass it will be many times more valuable than gold or platinum. Right now it costs between $70 and $100 per pound. You can reasonably expect that to become at least several thousand within the next ten years.
It doesn't matter what your peak load is. If you're in an area that's on the grid, then you want a grid-tied system, and therefore any power you can't generate on your own will come from the grid. At other times, when you have extra (e.g., a hot sunny day when you're out hiking), the power company buys it from you. There is typically a very strong economic incentive to buy a system that matches your yearly consumption, not your peak load. If it's providing less than your yearly consumption, then you aren't getting the best deal, because you still had to pay for a day's labor by the crew with the crane, etc., and you still had to pay for an inverter. The converse is also true: you probably don't want an oversized system. I have photovoltaics on my roof, and in my area, if I produce more than I use over a 12-month period, the electric company won't pay me for the excess. They'll just say, "Gosh, thanks for all that surplus power."
It's typically very, very difficult to make a realistic calculation of how long it will take a residential PV system to pay for itself. People always ask me how long mine will take to pay for itself, and I always tell them honestly that I have absolutely no idea. The problem is that energy prices are extremely volatile -- that's why they exclude them from the CPI. Remember just recently when gas was $4 a gallon? Historically, the price of electric power has always tended to go up, but we don't know how much it will go up over the 25-year design lifetime of our system.
What you can do is to consider all your local factors: latitude, amount of sunny weather, whether you have a south-facing roof, whether there is any shade on your roof, and current local prices for electricity. Every time this topic comes up on slashdot, people will make blanked statements about whether PV is economically viable. That's just nonsense. It depends on all those factors. If it was an utter economic no-go, the industry wouldn't exist. If it was 100% clear that it was economically favorable for everyone in, say, LA, then you'd see PV systems on the roof of every house in LA whose owners had sufficient capital to pay for the system. The fact that the industry exists, but is still fairly small, tells you that there's a lot of uncertainty about it. You're welcome to invest your money in the stock market instead, but it won't help with global warming.
Ain't gonna happen. Network effects are one reason. Another reason is that different devices naturally want to work from different voltages, but you can't step voltage up or down if it's DC.
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None of the elements being discussed are rare earth elements (which are indeed all metals). Cadmium and tellurium are not, and neither are copper, indium, gallium or selenium. This is too bad actually, since despite their name none of the rare earths, except of course for promethium, is very rare.
Tellurium is fairly common for an element of its atomic weight in the Universe. On Earth it is quite rare, but instead of 1/10,000 as common as gold as you would have it, tellurium has about one fourth the abundance of gold in the Earth's crust. See this abundance table.
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