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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.'"
ya, but for how long do they last
You know, $1/watt panels are good and all, but shouldn't someone be more concerned with making them useful? It doesn't matter if the panels are $0.01/watt if I still need the entire neighborhood covered in them to run the coffee maker. You need to get to the point where covering the roof of the house is sufficient to make a major impact on the power needed from the rest of the grid (if not replace it totally, a pipe dream).
I have always been worrying the environmental impact of the cadmium. Could some one show me that the cadmium used in the photovoltaic has little or no environmental impact please?
There is a spark in every single flame bait point.
if it turns out to not be vaporware, it may very well actualy make a dent in our use of coal and other fuels for generating electricity.
I've decided to Diversify my Holdings. I've divided my cash between my left and right pockets, instead of all in one.
"The cost to the consumer could be as low as $2 per watt"
Sweet! That's awesome, although I'll believe it when I see it.
about half the current cost of solar panels.
What!?! Where does one currently get 100 Watt panels for less then $800? Unless you are buying a few thousand watts worth (at which point I'd call it an industrial purchase and not a consumer purchase), the best price per watt I've seen is $8-9/W.
I'm in my right mind and I have the answer to everything!
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.
I am glad that we are making some headway in solar power, but without better and environmentally safe batteries I don't see the technology really being too useful yet.
a)How long do they last
b)How fragile are they
c)What temperature ranges can they survive
d)How strong light do they need
e)What environmental impact will the cadmium have
Sure, if it works all will be happy and dandy, but I somehow suspect there are some catches not mentioned here.
10% - 15% is not high efficiency for photovoltaic panels, 30%+ is high efficiency.
Cadmium... so not RoHS compliant, so not saleable at all in Europe and many other parts of the world. Oh dear.
I wonder if RoHS will be relaxed for solar energy?
Oolite: Elite-like game. For Mac, Linux and Windows
Electricity is usually billed per kilowatt-hour. Therefore, if these panels are to be compared to buying power from the grid, one would need to know their electric production in watts per unit time. If they generate a watt of power, thats great - but is it a watt per minute (pretty good), a watt per hour (not very good), or a watt per day (almost worthless)?
Damn_registrars has no butt-hole. Damn_registrars has no use for a butt-hole.
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.
$2/watt retail? I'm there. I'll take 5Kw worth of panels, a couple wind turbines, and backup diesel generator and the power company can kiss my big, white butt. Already have my battery boxes built, best start working on those wiring diagrams!
That's our life, the big wheel of shit. - The Fat Man, Blue Tango Salvage
Yeah, yeah, I know: Subjective term relative to current efficiency levels... still, they're pushing it.
You can't take the sky from me...
Let's be like China and make electricity the man's way - with coal! And let's go back to burning leaded gasoline so we don't have to fuck with this unleaded crap that limits engine compression. Also, catalytic converters suck. I always take mine off after inspection or go to shops that don't care. Also, we need to get rid of welfare and we need George W. Bush for another eight years! And fuck solar cells. Solar cells can't even power calculators properly.
Anonymous Coward Sig 2.0:
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Write in George W. Bush in 2008!
Management of the environment is constant compromise since nothing is perfect. However. Since burning coal is the major SOURCE of Cd in the environment ...a quick web search reveals a sense of the tonnage:
http://www.unu.edu/unupress/unupbooks/80841e/80841E0c.htm
a balanced view considers the following.
Which is cleaner?
a) a highly controlled manufacturing process
b) under-regulated coal bonfires belching Cd in the air and
disgorging Cd in the ash.
Bonus question: for extra credit what other nasty stuff comes
out of a smokestack?
---537
From TFA:
The cost to the consumer _could_ be as low as _$2_ per watt.
Anybody spot the weasel word? Then there is the $2 cost to the consumer, rather than the $1 which is the cited production cost. Also, the article makes no mention of what levels of incoming radiation these numbers were calculated for. $1/W means something quite different in Egypt than it would mean in Sweden. Is the $2/W derived from the peak efficiency under ideal weather conditions, or is it the average over a year?
Essentially, if you want a real estimate of the price of a power technology you don't want price per power, you want Energy per Life-cycle costs. So if these cells last for 10 years you want to know how much total energy they could be estimated to produce during that time, compared to the cost of the panel. Other aspects like intermittent production and so on factor in, but in any way, price per [peak ?] power output is not a very useful number from an economical point of view. For solar cells you want at least the estimated cost over a life cycle with the assumed weather conditions specified. Less than that and you can easily massage the data by making strange assumptions.
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
According to http://www.rohs.gov.uk/ on the decision tree link, "Fixed installations are outside the scope of the RoHS Regulations." and below that "Examples of fixed installations are: Domestic electrical supply systems (ring mains, fuse boxes and meters)" so we're good!
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
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.
This could be IT. Or, it could be another technology still in the works, "any day now". Despite the fact that it's been a long, long road dealing with the horrible mess of coal and other CO2 releasing power generation technology, it won't be forever. Cheap as dirt solar should rapidly surpass all other forms of energy generation : no complex, expensive plants like nuclear. No mining coal and having to deal with pollution. No dealing with commodity fuel prices, once the panels are installed they keep making power until they wear out.
Half the problem of fossil fuels could be solved in one stroke. Sure, it would take 20-30 more years before all the existing plants are replaced, but solar can in principle, in conjunction with a good method of energy storage, supply all the energy needed for electric power.
The solar panel is flat and doesn't move but is tilted toward the sun. That probably doesn't describe the instrument that measures the sunlight. It has probably changed since the last time I looked but we used to use something that looked like a glass hemisphere. You will also pick up a bit of energy if you have reflecting surfaces (like snow in the winter for instance). The bottom line is YMMV. The insolation is a starting point. As in all things, good engineering is conservative engineering.
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.
Solar became affordable years ago, for everyone except highrise apartment renters (no space nor say in their reality) and get rich quick scheme house flippers (have manuel j illegal slap contractor white on it, done, all repairs complete). for everyone else, normal middle class working people, who plan stay put in their house, it's been "there" for around a decade now. Current panels are rated 20-30 years, with maybe around 80% efficiency left then. I don't know on these new cheap panels, didn't see specs on it.
And if they made the coal and nuke and oil guys pay full price to produce power, where they would have to actually pass the cost directly along to the consumer, instead of the subsidies and incentives and credits they have gotten for years (cheap access to public land for mining, no environmental cleanup costs until recently, land seized for monopoly grid right of way and no money to the landowners, incredibly cheap per barrel cost back to the government/public till with NO auditing for oil and natgas, etc, indirect military cost to stay forking around in the middle east forever, and nukes, heavily subsidized risk insurance and government protection,not a single nuke plant has full "free market capitalist" risk coverage, the government has said they will cover some eventualities, that means the tax payer, armed guards forever, etc, solar became affordable two decades ago, and windpower further back then that. Turn about is fair play, the anti solar crowd are the first to cry "subsidy-it's not cost effective!!1!" and they always forget about their pet other conventional fuels, including nukes, being massively developed and deployed partially off the tax payers back.
Anyway, this cheaper stuff is quite good news I say. The quicker we can bump coal nukes and oil off the head of the list for power the better. Check the headlines, the three biggest threats the planet faces, shit that causes wars and stuff, is "who is allowed to develop nuclear technology" and "global climate change from greenhouse gases" and "we are running out of clean fresh water from being contaminated mostly from the petroleum and spinoff industries".
No one is going to war over a bunch of roofs covered in solar panels. Solar PV is so seriously carbon neutral and clean it ain't funny, it barely registers. There's a little from manufacturing, but negligible compared to coal or petroleum, and the toxic waste is of much less import than radioactive waste, uranium tailings, coal slag and exhaust, etc. People right now are being murdered over access to petroleum in the middle east and africa, and pretty soon now another bogus war over who gets to use nuclear tech, and that war could actually go nuclear weapons. This is insane when we have alternatives!! And coal is so damn dirty and obvious, even the industry admits it now, it's just all around bad news, it needs to stay stuck in the ground forever.
Solar, wind, hydro, geothermal, biofuels, and eventually some combo of the above to get to hydrogen, that is our energy future if we want to avoid more big wars and poisoning ourselves out of a planet. Artificial fusion is ridiculous when you have a huge fusion reactor right outside half the day. If we keep using oil coal and nukes-no hope, none, wars and a completely ruined environment. Simple as that. Yes, those three are energy dense, they are also the worst for being "major OMG levels risk dense" and as such, should eventually be banned from use.
If one day a flush of hail breaks the photovotaics on my house, and some of those pieces get all over my house, will the EPA declare my house "extreme poisonous" and "unsafe to inhabit"?
There is a spark in every single flame bait point.
flywheels are an interesting method of energy storage undergoing contemporary research.
in my book they're cool because they're clean and simple.
there was a good article in science news a few months back, but it's subscriber-only.
here's another.
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.
It doesn't matter how cheap and efficient solar panels become. The electric companies will do everything in their power to keep this kind of thing off the market to ensure the status quo.
More is needed, though - even with cheap and plentiful solar cells you're still up against some physical limits. You've only got so many square feet of southern exposure you can put panels on - and it's not anywhere near enough to support your current level of electric power consumption. Keep in mind that solar panels are rated at "full sun" and in the middle of winter you'll be lucky to get 10% of that on a bright sunny day.
So a good place to start is to find ways to reduce your power consumption. Not "feel good" little reductions, but serious cutbacks. Think about things like skylights in kitchens / bathrooms (free lighting), better insulation and weather stripping, and even some automatic controls on things like lighting, heating, etc. - these will remember to shut off the lights, turn down the heat, etc. even when you forget.
Pick up a small watt meter; something like the "Kill a Watt" can help you discover where the power is going. You'll find that a lot of it is pure waste and easily eliminated. Use task lighting instead of lighting up the whole room / house, look for more ways to reduce consumption.
You'll have to make some concessions and adjustments to live a low power consumption lifestyle - it's up to you to determine how far you can comfortably go. But if you can cut your consumption by 50% or more (very possible) then you're getting to the point where those solar panels can supply enough power to keep you going.
And you're going to need some kind of backup generation for those dark and dreary winter days. House sized generators are usually NOT cost effective, battery banks are expensive and troublesome. Grid-tied systems are clean and easy - but get the facts from your local utility before going this way. Some are very reasonable, some want to pay you their "generated cost" (less than wholesale) for the power you put into the grid - but charge you peak rate for the power you pull from the grid. This can wipe out your solar savings; be careful. Choose which ever of these best fits your needs and hope you never need to use it.
Now this hocus pocus about the after tax situation is wrong too. If you want to include that then you have to include it on the 8000 dollars as well so Since the 8000 cost is after taxes, there's no point in calling the return on investment after taxes. Or if you want to then it costs 12300 of pre-tax income to buy the 8000 panels.
The ROI is negative since 437 electricity minus 640 interest is a 200 loss every year.
Some drink at the fountain of knowledge. Others just gargle.
What worries me about solar cells is the life-span. For such a big up-front investment, would be good to have a guaranteed 30-year lifespan for them, but I have my doubts.
Semiconductors (having no moving parts) are effectively immortal, granted, but the regular thermal stresses that full-time solar cells see every 24 hours can make them prone to cracking I believe - after which they are pretty much bricked.
"I bless every day that I continue to live, for every day is pure profit."
Not to be overly cynical, but I've seen a lot of things described as "nearly ready" over the years, and it doesn't mean squat. It may be one year from production, or it may be twenty.
Call us back when it's *really* ready. That is to say, you've actually got a contract with a reputable manufacturer specifying when they'll be delivering the goods.
Now we need a DC power wires and Outlets in homes to get rid of the DC-AC and then back to DC waste. It's better to have a DC to DC transformer then an ac to dc transformer and in homes a lot people have ac to dc wall warts and PC that have build AC to DC PSU's.
If I live on a mountain miles from the nearest powerline, the cost of gaining access to the electricity grid is going to be very high. It may be cheaper to generate my own power, but it will still be an expensive option.
If I live somewhere like most populated areas then the cost of connecting to the electrisity grid will most likely be quite low, making renewable energy sources uneconomic.
Example:
Battery bank: For a practical bank, to provide adequate power for a family home, we're talking into the thousand+ Amp-hour range. That's going to mean a bunch of 2 Volt or 6 Volt cells, in all likelihood. These cells cost nundreds of dollars each and we'll need quite a few.
Inverter/Charger: To meet the needs of the average family home, you're talking many kilowatts and many dollars. If you're going to do it, get a good one, but they aren't cheap.
Cables: Checked out the price of copper recently? It's expensive, but you're going to have to pay, unless you know of some which has "fallen off the back of a truck". You cannot expect to skimp here, unless you're partial electrical fires.
Photovoltaic array: Forget the Slashdot hype, supercheap, uber-efficient solar cells are still just the empty promises of researchers soap-boxing for money. Instead you'll have to buy the ones available right now and they aren't inexpensive and you're going to need a lot of them to provide sufficient energy for the average family home's usage. We're taling kilowatts again, at least 2-4 kW in fact. At around ten bucks per watt.
I've heard all the stories about people who maintain a family of seven on an old truck battery and a solar panel they found behind a dumpster but they're all just horseshit. Spend a few hours studying basic electrical theory and you too will see that such stories are crap. Even a frugal family, well-versed in the needs and capacities of RE systems would be hard-pressed to exist on the electrical supply from anything but an expensive setup, assuming they paid for all or most of the components.
Renewable energy projects are fascinating and wonderful but the fact remains that unless you are in a position where you have no alternative, it's simply not economically viable (or at least practical) for most people. Those who choose to go off-grid either have no choice, or are deeply committed to "the cause" and have deep pockets.
And before you start claiming otherwise, remember that other people have Google too and ten minutes of searching will reveal to them the costs involved. Forget about the smoke-and-mirrors...we need to make sure people understand the fundamentals of the cost of RE before we try to convince them it's the right thing for them to get into.
Very good point!
Consider the modern hard disk drive. These have lifetimes measured in decades. With magnetic bearings surely we can create a decent flywheel system that can do the trick for stationary service. They won't do the trick for vehicles though because the loads are too great. I have read about "air cars" and this seems quite reasonable since the internal combustion engine is basically an air pump.
Would you care to calculate what the engineering parameters for a flywheel storage system for a house might be?
A good place to start is that at 10 cents per kwh... and a 100 power bill we are looking at 1000 kwh's power consumption per month.
One might want to buffer a day's worth... say 1/25th. 1000/25 = 40 kwh.
This is 40,000 watt hours and in my battery example that is $18,250 for 1/4 of that to roast xmas dinner.
Clearly one would use say a wood stove.
One could say buffer 1/2 a day instead of a day. That would be 20 kwh and maybe nighttime electricity use for the average home owner is less than daytime usage... for me it is.
If one's power bill is $100 per month then this will finance about $12000 in capital costs at 10%. There will be maintenance expenses and operating costs and infrastructure costs as well.
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Here is my observation. It costs during construction about $1 dollar per square foot of building envelope to super insulate a house. If you do this you can save over $200 per month in peak heating / cooling and overall here in Calgary I would save over $1000 per year and would do it except I have to tear this house apart in order to do it.
If my house is 40x50 = 2000 square feet then I have a building envelope of about 4000 square feet so the additional insulation costs me say under $5,000 and I get a pay back in say 5 years (or less) and I can chuck the furnace.
Builders are not doing this yet.
After the house is finished I need to tear the walls apart and rebuild them and this is more than a $50,000 touch. A $50,000 cost to save $1000 per year at 10% has a negative ROI.... so it never gets done.
The thing is that one can save $100 per month average in energy by investing $5000 into fiberglass insulation. We can pick this insulation up in any lumber store in North America at least. It requires zero maintenance and close to zero intelligence and its operating costs are non-existant.
Hence, if one wants to be environmentally friendly it would seem to me the thing is to invest in the simplest technology possible first and especially so with such inviting numbers. Yet, the vast majority of people are not doing this.
Then we have the tragedy of the commons where the few who are concerned enough to actually build a super insulated house make no difference in the grand scheme of things.
Its the same as the cyclist. He/she might be a very energy efficient person but the waste from everyone else makes their concerns and their efforts irrelevant.
On a related subject, my city wants to charge me on an average basis for the garbage I create. I refuse to buy the over-packaged foods. I buy most things in bulk. I do not open cans. As a result I have less than 2 safeway bags of garbage per month. Still I am suppose to save this for months on end to fill up a standard trash bag because they have these rules that they don't want to pick up a little Safeway bag.
Then I am expected to pay for a service that I don't use and its my money that subsidized my neighbours' extravagance. Next the city wants to up the rates so they can institute a "better" way to handle the trash.
An intelligent solution IMHO would be to surcharge those who create mountains of trash with their clearly wasteful consumption patterns and to reward people who are fruggle.
In our society, it doesn't seem to happen that way. The guy who rides his bike to work is still expected to subsidize the guy who drives an SUV what weighs in over a tonne. Then when an oil war shows up because Britain and the USA want to liberate Iraqii oil in order to maintain an unsustainable lifestyle... that guy on his bike will be told its his duty to carry a gun and kill people.
Also $1/watt is just the cost of the cells. By the time they're mounted in a panel, panel installed, and all the rest, the cost will be many times higher.
Here you go.Here is a major reason why a number of companies are interested in Ava's particular approach.
I prefer the "u" in honour as it seems to be missing these days.
And the 'war of the currents' starts anew....
read the avasolar site.
I prefer the "u" in honour as it seems to be missing these days.
Depends on your application.
In space constrained situations I suppose you can be concerned about maximum efficiency and not care about cost. But for the majority of the market cost is the foremost concern. This is why the dollar-per-watt is such a big deal.
Congratuations to all those who produce higher efficiency products, but that's not what's going to win over the majority of the market. To win over people who don't give a rats ass about the environment you need to focus on costs rather than efficiency.
Let's put it this way, a typical 200sq ft suburban home has enough roof area that even at 7% efficiency you would have more than enough space to fullfill that households electricity needs and perhaps enough left over for the marjority of their transportation as well. The space isn't a problem. The problem is the cost. If the cost could be reduced significantly below that of grid electricity over the product lifetime then it would most definitely happen.
Moreover, if it was cheap enough, you could also put panels on the fencing around the yard. In many American homes that would double the surface area. Also you can use curved tiles on the roof again significantly enlarging the surface area. Surface area is so low cost for most applications so what's the significance of efficiency?
But this is all academic because the key point is that the original target market isn't the residential market anyway. The first target market is membrane roofed industrial buildings. This is already going on big time in Germany and Spain.
Supposedly, China has our dollar against a "basket" of money. But if you go and map the dollar against all other money, you can watch it drop by roughly the same amount. Not so with the yuan. it has dropped a little, but only a little. IOW, we are still being held hostage to the communist regime. SO, we will be able to sell everywhere except to CHina via dollars. Of course, the good news is that the longer that China does that, the madder Americans are going to get and and we will quit buying. In addition, we will get smart and simply sell to them in Euros.
I prefer the "u" in honour as it seems to be missing these days.
If they work, then Americans will be buying cars equipped with these by the droves. The reason is that by tieing it to the house power, then these serve as a back up for running the homes. Imagine the homes all over who have back-up generators. Instead, they simply use their cars. I suspect that we will see ALL homes have at least 2 cars. Again. I would not be surprised to see them sold and buried in the ground to hold electricity from solar (while using geo-thermal heat pumps to heat/cool the homes).
I prefer the "u" in honour as it seems to be missing these days.
What matters is costs / watt, assuming that the efficiency is not so low that it requires too much space. In the end, homes could start moving to this, and when high efficiency, low costs solar cells via other methods appear, they could move over to that.
I prefer the "u" in honour as it seems to be missing these days.
Take a step back from 100% independence, forget about the batteries or selling back to the grid and just take what you can get for 6-8 hours a day. That will leave a hefty dent in the production needs of our power generation infrastructure which is pretty much built around that time period. The costs of that will be reduced tremendously.*
Your two year figure is very good. I see no reason to complicate it with batteries and sell back. Even a poor efficiency curve (within reason) only effects this span by a few months. We'll continue to need our power plants for the forseeable future and I don't think this tech needs to eliminate them to be worth while.
*Don't expect your utility companies CEO to accept a reduction in revenue simply because their costs have dropped significantly.
Platform advocacy is like choosing a favorite severely developmentally disabled child.
It's not really possible to do this. DC requires considerably larger wires unless you really bump up the voltage, otherwise you wind up with very serious losses from wire resistance. Plus nobody wants to have 1000+ VDC wiring going throughout their home, there are serious safety issues. If you look at history you will find that, in fact, DC came first but quickly lost out to AC due to wiring, wiring losses, and safety issues.
Maybe we will start to see more DC when we get low-cost room temperature superconducting cables. Running DC over superconducting cables is actually used in a few places in the U.S., by large power companies, because it is extremely efficient (when you have a superconducting cable) and requires no synchronization.
-Matt
1.21 Gigawatts at $1 a watt, no thank you I'm sticking to lightning.
I enjoyed the quick estimates and calculations of your battery example, so I read this post too (especially as I've been interested in flywheels for quite some time); also decent.
1/
I was confused by your calculation of your house envelope. You appear to be calculating square footage for one storey, then multiplying by two (for the second floor). I think you should be computing the exterior surface area of the house, not the square footage.
2/
Regarding your dismay over the meaningless contribution of the cyclist. Although it's disappointing, if you pursue that line of thought, I think it's true changes made in Canada (solar, batteries, flywheels, no garbage, no combustion engines, etc. etc.) are meaningless in a global context, given the growing energy consumption (and requisite generation, mostly being done by coal fired plants) in China and India.
3/
Regarding infrequent garbage collection in your city. If you produce less than two small garbage bags per months, although slightly inconvenient to do, you storing them is a good idea. Assuming everyone did this, less frequent pickup would be possible, thereby saving money (capital cost such as equipment, wages, fuel, etc. and ecological cost such as fuel, exhaust, etc.). You simply need an airtight container that will hold, perhaps, four small garbage bags. Then your garbage pickup could be reduced to once every two months!
Anyway, nice posts.
For those specific purposes, solar is a winner because in our situation money is no object.
Using solar to power our society though? load of crap. unless some mega break through happens and solar cells reach 90%, they are just an expensive novelty.
If you mod me down, I will become more powerful than you can imagine....
Is someone able to provide us a breakdown of how these panels compare to other available solutions?
- how well do they perform as they age? (some panels lose 50% of their capacity in their first 7 yrs)
- how delicate are they? (some panels are damaged by RAIN unless protected)
- are they flexible at all?
- can they be fitted to curved surfaces?
- is it easy to fit them to non-square shapes, such as sides of a peak of a house, without the "checkerboard edge"?
- also getting into the delicacy aspect, how well do they respond to vibration? (think solar powered vehicles)
- how are they for weight?
I'm assuming they produce electricity on par with existing solutions, and are reasonably inexpensive.
Those contests where the solar powered cars have to drive from A to B make excellent benchmarks for solar technology, as they press all of the above to their limits. If they want to impress me, make a solar car that clears the room.
I work for the Department of Redundancy Department.
I live in Colorado and I find this story interesting in relationship to another story about a year or so ago about a man in Colorado who installed a roof's worth of solar electric panels which gave him juice to spare. The spare electricity was fed back to the grid, causing his electric meter to spin in reverse. When the local power company found out about it, they installed a "special" meter that would only spin in one direction (in their favor, of course). I think we need some legislation to require power companies to buy back any excess generated power. CB
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.
Try visiting Tracy, Stockton, or any other central valley city in California and you'll change your tune real fast. HOT in summer and COLD in winter, just like the rest of the country.
I get the building envelope as follows:
40*50 = 2000 square feet.
40+50+40+50 = 180. I made the walls about 10 feet high so that is 180*10 = 1800.
1800+2000 = 3800 and I rounded it up to 4000.
Currently we put R20 in the walls. R20 costs just under 70 cents per square foot in Rona and Home Depot.
Thus R30 will cost about $1 dollar. R20+R30 = R50 for the walls. Currently ceilings are typically insulated to about R30-R40 so we simply add another R30 to that. This gives walls which are about 1 foot thick. Walls are built of 2x6, 24" on center. It is perfectly fine to rip the 2x6 into a 2x4 + 2x2 and use a spacer to create a cavity that is the proper distance for the insulation. Hence the actual construction costs are about $1 per square foot of building envelope and a wee bit of extra labour. From this you can deduct the cost of the furnace because you won't need one. You can add the cost of a small radiant in floor heating system or even radiators around the perimeter and with a heating load this small you can use a simple hot water tank as a boiler. I did this is my garage which is 670 square feet and the tank easily heats the building even when it is 40 below. That building was built to R20 standards not R50 because at the time I listened to a contractor and like most of them, they don't know how to do these energy calculations and hence their recommendations are not worth listening to.
Another thing to note: Consider the perimeter of the house is 180 linear feet. This is about 90 studs when done 24" on center. Studs cost about $5 bux. That is less than $500 in studs on the outside walls. Even if you incur a few extra bux here it isn't going to add up to a hill of beans on a finished house. About the only difference this makes is that your window sills are say a foot deep. This is wonderful for plants. My grandfather built a house from logs and the walls were a foot thick at least. When I bought the house I am in now I was dismayed that I could not even put a plant in the windows so I built window sill extensions.
This house has R12 or even less in it. It is so hot in the summer I hate it. This illustrates just how bad construction is and most houses in North America fall into this category. We have burned off a HUGE amount of the non-renewable gas supplies and also oil supplies because of this. When we start to have shortages I hope people realize that had these resources been conserved and managed well, then our supplies would have easily lasted into the 22 century. As it stands now I think those who say we are past world oil are correct and that Mathew Simmons' estimate that oil will pass $300 per barrel shortly is also unfortunately correct. We passed the peak of North American natural gas production January 2001.
Because of this much of the North American fertilizer industry is permanently shut down. Natural Gas hit over $17 per gigajoule and it will hit this again in the not too distant future. We will be likely facing a major crisis before 2015.
Next: Garbage pickup.
The garbage truck goes down the back alley every week. IF I put that little Ssafeway bag in a big garbage bag then they are happy. If I put it all by itself in the garbage pail they leave it. They left two (2) of them all summer long as I was not in town for most of July and August and didn't realize they decided to leave them. Since there was some raw bones and a fish head in one of the bags it was pretty high by the end of August. Their excuse? They didn't like me using two little Safeway bags.
Now for the cyclist. I'm all for him. He may not make much difference but at least he's trying and I pat him on the back for the effort he and others make.
Nice try. You are correct that distributing DC is inefficient but not for the reasons you mention.
DC is incredibily difficult to change voltages with compared to AC. Sure, there are DC-to-DC converters but if you look inside that black box you will discover it is transformed into AC and back into DC with pretty big losses. This isn't done unless there is some overwhelming reason to do it.
There is no difference in the wire between AC and DC, even over long distances. There are no additional losses with DC. Resistance is resistance and it is the same between DC and AC. With AC you also have impedence which isn't a factor with DC.
Because of impedence, over very long distances actually make AC less efficient in a transmission line. However, it was DC you couldn't use a transformer. So even though AC does incur some complications, DC is out of the question because (again) the inability to change the voltage.
Safety? DC was originally touted as being safer (by Edison) than AC as a criticism of Tesla. Edison was winning for a while but eventually lost out because Tesla was correct about distribution issues. I think at house current voltages a claim can be made either way and it is difficult to say which is safer. Both cause nasty effects on humans.
Superconducting distribution wouldn't change the situation between AC and DC either.
The reason we have AC today isn't losses or safety - it is transformers. Not the little ones in power cubes but the big ones out at the substation. The little ones might be replaced by switching power supplies, but the big ones aren't going anywhere.
The one smart move might be to change from 60Hz to 400Hz. It makes for smaller transformers, smaller capacitors (the other big thing at electric substations) and smaller filter capacitors in power supplies. Lots more efficient overall. Very hard to change the infrastructure that is built around 60hZ though.
Kind of how you feel when you take food out of the mouths of the poor to make alternative fuels.
So the whole operation needs to run undegraded for 4 to 4.5 years I estimate for break even.
The current payback period is about 7 years now, with batteries. Even a reduction to 5 years would have a considerable effect. Thing is is pretty much a lot of hardware is rated for 10 years or more. If you continue using the equipment for the full 10 years you're basically getting free power for three years. However by upgrading after 7 years you're getting better efficiency. What could be done then is to add to the system. Say add more PVs then an inverter.
FalconShould there be a Law?
This was looking good until i read about the cadmium. This is somewhat of a concern especially when the panels needs to be disposed of. Cadmium is a rather unfriendly substance.
I do wonder if with the right economy of scales and improvement in manufacturing efficiency if the present common solar panel technology could be made more inexpensive, i have heard that perhaps as production scaled up the price of the present technology would come down some more and become more affordable.
4000 / 365 = over 10 years. And that's assuming 24/7 production. Unless you are doing this in the north pole during the summer, that is impossible. It's more like 20 years for payback.
You do realise that he was right? The green revolution along with declining birth rates in the western world has ensured that we have enough food - but starvation is a reality elsewhere.
That's the thing about many, I won't say all because I consider myself one, environmentalists don't and won't consider, as people improve their economics they have fewer children. Up until recently the countries with the highest population growth were China and India. However now that their economies are booming their population are leveling off. A concern in China is that in a generation or two there won't be enough working adults paying for an aged population. Whereas now there's something like up to 10 people working for every retired person then there will be only 3 workers. Where population growth is now a concern is in Africa which due to conflicts and politics is doing poor economically.
FalconShould there be a Law?
Not trying to say the tech is not possible, but like every other "revolutionary" or wonderful new tech (or drug) announced from the "Lab" of some university I'll be impressed when I can buy it.
Take a look at the revolutionary drugs/tech that was supposed to change our lives 10 years ago and ask where is it today?
Everything announced is ALWAYS 5-7 years away seemingly.
11-13% is high efficiency now?
Regular commercially available solar cells are usually 17% and the various other 'gonna be available real-soon-now' technologies are claiming 40%.
I understand that these are cheap to build and may be a good deal overall but they are not high-efficiency.
You can't take the lowest available efficiency and call it high.
...but solar doesn't exactly do much for those of us in Alaska or other high latitudes, particularly in winter, when the sunlight is least (Like Barrow's month of darkness), and energy demands are highest, thanks to heating needs.
Here's the thing. It always seems like solar cell wattages are not average, but rated assuming a sahara desert level of sunlight. So, you'll rarely see 1watt out of a 1 watt panel - and if you did, it would be for perhaps an hour or so on a july day, and not much more. On average, you would get a curve going from zero to something like a fraction of the watt, and from there, you can extrapolate that you'd need a lot more solar cells to actually power your house.
This is my sig.
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.
I too have been into renewables for years, however even though I live in a major city, downtown Minneapolis is less than a 20 minute bike ride for me, after I buy the building of apartments I live in and save money I plan on remodeling the building to be more energy efficient and would like add some PV panels. Eventually I want to build a home off the grid, someplace that the closest powerlines are miles away.
How old are your children? If they are old enough maybe you can show them how the system works. Then after a few years, or more if they're too young, they could apprentice under an installer in the area. If they wanted to major in Electrical/Electronic Engineering in college this could be valuable experience. Turn something that seems like a negative and turn it into a positive.
Should there be a Law?
Cheap as dirt solar power means high energy consumption. High consumption means increasing prices unless we cover all deserts etc with solar cells. That, on the other hand, is bad for the local ecology. Besides, I wonder if it will affect global temperatures if all the land starts being covered with energy absorbing materials. That's how it always is. Energy is always either expensive or ruins the environment. This is of course true for all products, but it seems especially true for energy.
Even if we do get cheap electricity, there are still technological leaps to be made before that becomes an efficient way of powering cars, let alone trucks, cargo ships or worst of all: Aircraft. Also, industries like to keep running 24/7. Solar power is only really efficient around noon and completely inefficient at night. Now there are ways to get around this, but they are very expensive. The even bigger issue is northern countries that get very little sunlight during the winter. Sure, they can import power, but that means power will be wasted in the grid.
These issues can be solved of course, but not for free, and not soon, and there goes the idea of cheap solar power in our lifetime. Its a bit like fusion. It seems to be the solution that's constantly 30 years away. Solar power seems more probable than fusion, but its really the exact same issue: They both work, but neither produces more energy than what is put in. Sure, solar cells produce more power than what is put in if they are placed at the optimal spots and used only as a complementary power source. But if we want to use them for more than 50% of the global power consumption, we have to start putting them at pretty bad spots too, and we will lose so much power in various conversion and transportation processes necessary to counteract the bad sides of solar power. A global average of 5% efficiency when converting the sunlight at the working solar cell to energy at the consumer will seem very optimistic, even if the cells themselves could convert sunlight to electricity at 50% efficiency in optimal conditions.
So no, this is not the solution any more than fusion is. Wind, various forms of hydro power and solar power in combination might eventually turn out to solve the big issue, but in the end, energy will never be cheap again.
for proper operation you don't want to discharge the batteries too deep
That's what Deep Cycle batteries are for. They are made to almost compleatly discharge before recharging.
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.
Today the payback period for a properly designed system can be as low as 7 years, ie it takes 7 years to pay for the system. Since most hardware components are warrantied for at least 10 years, that leaves 3 years of free energy. And because off the grid systems save the owners from paying an electrical bill more and more Green lenders are offering higher mortgages to pay for off the grid systems.
FalconShould there be a Law?
AC is usually not in the cards if you are trying to achieve energy independence.
AC isn't needed much if at all in a properly designed and constructed building. Neither is heat.
Though I now live in Minnesota, which shares a border with Canada, I used to live in Florida and the last year I lived there I never used AC, or heating. Well, I'd turn on AC for a few hours once or twice a week to try to prevent mold buildup in the ducts because of humidity.
Should there be a Law?
Most investment advisers will suggest that you put most of your investment money in stocks, but some in bonds.
Actually it greatly depends on the age of the investor and their plans. Someone in their 20s and 30s should most definitely have the bulk of their investments in stocks, aggressive growth for someone in their 20s and growth in their later 30s, for instance. However as they age and get closer to retirement their portfolio should shift from growth to income.
No, I'm not one myself but my brother-in-law is a Certified Financial Planner, CFP.
FalconShould there be a Law?
Typical, it's actually to their advantage to have you over-generating since in the US daytime A/C is
a big load and they get stung with their peak (installed capacity) charges at that time of day.
Every w/h they don't get from you during peak costs them a lot more than their residential rate , probably 20x.
So instead of taking the long term view (not just save the world, but how many $$$ will this make us) , some cheap bastard decides they'll win short term by screwing the domestic generators.
It's not even as though doing this saves them money, it's costing them big time.
It remains to be seen: which will happen first? Affordable solar power, or the Year of Desktop Linux.
- Night (50% averaged for the year).
- Suboptimal angling on the panel relative to the sun throughout the day (guessing pi/4 since I'm too lazy to do the integral).
- Weather (highly dependent on location but this report says 54% in the northern hemisphere, let's use 30% to account for light that manages to get through the clouds).
- Panel efficiency (12%).
- Conversion losses. I should be including losses converting solar panel DC into the AC most household appliances use, but let's be optimistic and say these panels spur development of DC appliances.
- Battery efficiency. Unless you plan to use your lights only during the day, you're going to have to store electricity for night use. Lead acid batteries are about 90% efficient. Wild guess, but say a half of your daily electricity use will be drawn off the batteries, yielding an average 95% battery efficiency. Yeah you could draw electricity off the grid at night, but since we're hypothesizing DC appliances and throwing away conversion losses, I think this is the smaller of the two.
Phew. So what do we have? 1600 W/m^2 * 0.5 (atmosphere) * 0.5 (night) * pi/4 (angling) * 0.7 (weather) * 0.12 (panel) * 0.95 (battery) = 25 W/m^2. That's probably a more realistic figure to use if you want to calculate how much electricity use the panels will save you over a year. The average U.S. home consumes about 1 kW (averaged over the year), so to completely take each home off the grid would require about 40 m^2 of panels. You'd probably want more than that to get you through the Winter months and long bouts of bad weather, but that's very location-specific. We'll just use 40 m^2 and calculate a minimum.Assume the $1 per Watt figure is under ideal conditions (companies love to do that). 800 W/m^2 * .12 = 96 W/m^2. So a square meter of this stuff will run you $96. Multiply by the required 40 m^2 to yield $3840 per home.
Figure an average electricity cost of $0.13 per kWh (in the higher priced areas where this stuff will be used first). Average home burning 1 kW (yearly time-average) would thus spend 24*365*1 kWh = 8760 kWh for the year. At $0.13 per kWh, that's $1139/yr in electricity costs. Ignoring installation labor, the panels would pay for themselves in 3 years and 4.5 months at earliest. Adjust up depending on your latitude and weather. Adjust down if you aren't as power-hungry as homes in the U.S.
I think we have a winner.
First, please check www.cia.gov and compare china vs. USA's economy. We are still bigger. In addition, we still export more than they do (though we are a lot closer than we were 8 years ago).
Second, few things are NOT made here. The problem is that the majority of our low-end goods come from China. Basically, we have the ability to scale back up, but it would take time.
Debt is our biggest issue. In particular, federal debt. reagan and W. have hurt america badly. For all the gripes about clinton (and poppa bush), I think that they were a lot closer to where we needed to be.
I prefer the "u" in honour as it seems to be missing these days.
It appears the poster above needs to look up the definition of a Watt. If they do not bother I can point out that something that generates one kilowatt that runs for one hour gives you a kilowatt hour. If it runs for twelve hours that is twelve kilowatt hours. Watts measure power consumption or production at a given moment; you multiply that by the number of hours it runs for to get the billed amount in kilowatt hours.
I worked on amorphous silicon thin-film solar technology at BP solar (the old Solarex) years back. The aSi panels had a number of good attributes but we could never get the $/watt down below grown silicon. I'm glad to see a similar technology succeed because thin film offers mechanical properties in terms of light weight and yeild that make it ideal for building-integrated installations.
Scruting the inscrutable for over 50 years.
For heating houses, wood makes a lot of sense (especially compressed pulp/sawdust). Wood furnaces are incredibly efficient and it is a renewable resource.
.0017 acres of land. So it seems that you could sustainably heat your house with less than 0.1 acres of land if you can get by with 1 cord of wood per year. So that would be great for people with fairly large properties (the size is about 66 feet on each side).
About half way through: http://www.na.fs.fed.us/pubs/silvics_manual/Volume_1/pinus/strobus.htm they list the yield for white pine (in a *natural* forest). It's somewhere between 300 - 800 fbm per year per acre (assuming harvesting of 50 year old trees). Assuming 1 cord is about 500 board feet (a number I pulled mostly out of my ass since you can't really convert reliably) and assuming 300 fbm per year, this means that 1 cord of wood represents about
But in terms of land use a ground source heat pump driven by solar power (with batteries) will take up a lot less room.
Ulp... in fact you are right. I don't know what I was thinking. The only real problem is converting the voltages to reasonable values at the home.
-Matt
For most cooking, including the turkey, forget about turning sun into electricity and using standard appliances. Keep it simple and use a solar oven.
Solar oven links:
http://solarcookers.org/
http://www.sunoven.com/usa.asp
To cool a house without using electricity, use solar energy to circulate air which is cooled by the earth.
http://www.enertia.com/Science/HowItWorks/tabid/68/Default.aspx
With TOU rates you need a smaller system to reach zero so the rate structure does make a difference.
which means the pannels would have to last at least 34 years to recoup the cost invested in installing a solar system.
You may want to readjust your figures. The last numbers I saw on ROI, Return Of Investment, showed the payback period was 7 years. In other words it took 7 years to pay for a properly designed solar system in a sunny location. With typical components having at least a 10 year warranty that means that after 7 years you get three years of "free" energy. Of course that's for a good system in a good place.
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)
Those wind gennies get government subsidies as well, not as much as others but some. Yea, Minnesota produce several megawatts of wind power, as does both of the Dakotas, and they can all produce more. I read of a USGS survey that concluded the Rocky Mountains have enough potential wind power to supply all of the electrical needs of the US.
FalconShould there be a Law?
You're the second person to talk about Deep Cycle batteries but seemingly only read the name. If you follow even the wikipedia link you will find it saying they can be discharged up to 80% for several cycles, but the reality is you don't want to routinely discharge them that deep. They will deliver far more watt hours discharged to only 50% or less.
As for the payback period (not sure why a link to wikipedia here) even grid-tie solar panel systems never pay for themselves, ever, compared to just putting the money into the mortgage, except in certain places with large subsidies. Payback for an off-grid system is a different story, in that there is no grid power to compare it to, only other forms of off-grid power. I have not done the math but would like to see what system you are comparing it to that costs more than solar over 7 years. Do you mean pays for itself vs. diesel generator, or something else? As noted, with a solar system you want a generator anyway, to deal with cloudy periods and special peak loads, though of course it can be a smaller one run only when needed compared to a full-time.
Has it been over a year since you last donated to the Electronic Frontier Foundation
Using the panel for 20 years gives you electricity at $0.10/kWh, but with accelerated depreciation you get to set the future cost of electricity against today's tax bill. That makes this kind of solar power very attractive to retailers.
With the world slated to end in 2012, all of us should really dump all the money we can into energies that could prolong our inevitable deaths. Granted, there may be some left wing conservatives who really want coal to lead us into the future, but who really wants to go down without a fight? This right winged liberal (me) says, let's fight til the last momment, then take the energy saved in our strategically placed battery cells to the grave with us.
WWPD - What Would Picard Do?
Actually, both statements are true in a way: it's difficult to change DC voltage, so we either have to have 10kV in the house, or transmit 110V long-distance. Transmitting low voltage long distance is very inefficient because of wire losses.
This interview with Nanosolar CEO Martin Roscheisen (coming on line this year at $1/watt wholesale price) http://earth2tech.com/2007/07/30/10-questions-for-nanosolar-ceo-martin-roscheisen/ says that he feels that vacuum based processes are not going to be competitive. Doubt he's getting 13% efficiency though.
Well, 1 kilowatt for an hour costs me 25 cents (thereabouts).
WOW! Counting all of the fees and taxes, I pay less than 12 cents per Watt Hour.
Even so when I remodel the building I still want to install PVs.
FalconShould there be a Law?
If you want to make a 'fair' comparison to fossil fuel sources, okay, great, but don't forget the total cost - include the environmental cleanup costs of each. The environmental costs of making the panels and what to do with them after their useful life is over, and the environmental cleanup costs of coal (production, transportation, processing, burning, the cost of the plants, etc.). I bet your calculations will come out differently then. :)
If I generate more than I use, then they don't send me a check, they just say, "Thanks for the free electricity." If I overproduce, it means I goofed big-time, because I spent more money than I needed to on my system
Do you do net metering or do you do guerrilla solar? I ask because with net metering you're paid less for power you put into the system than what you pay for power you use that's theirs. But you're right, if you produce more than you use then you're providing them with free power.
FalconShould there be a Law?
25 cent/gallon gasoline?
How many KWH are in a gallon of gas, anyway?
Are we moving closer to $$/joule pricing (or $$/MJ, dunno scale)?
No one would ever deploy an off-grid (i.e. battery backed) system and expect it to make financial or other sense. The only reason to deploy such a system is if you have no way to connect your site to the grid.
You're partially but not compleatly right. It can cost a builder tens of thousands of dollars to have the power company a couple of thousand feet:
"In nearby Marlboro, Sunny and Nat Tappan live in an older-style off-grid home, about 2 1/2 miles up a hill off a dirt road on an isolated 90-acre tract. The rustic, timber-frame house, which sits next to a pasture with sheep and chickens, has a composting toilet and no running water (they have a well). Sunny and her former husband bought the property 18 years ago and spent a few thousand dollars on a solar power system. Connecting to the power grid would have cost $80,000, but Sunny, 53, had no interest anyway."
FalconShould there be a Law?
Deer Balloonhead, our research indicates that you come outside not very often and usually not when the sun shines. This means that the sunshine that was meant for you is wasted every day. You are aware that we all need to conserve energy, that is why we are asking you now to turn off your portion of sunlight so as not to waste it.
This space is intentionally staring blankly at you
You know, it kinda makes me wonder how that increase will happen.
... In which case people buying energy-saving appliances will make almost no difference to the total.
... In which case they can build their own power plants, thank you very much. Electricity can't even be transported over _too_ large distances, so it's not like more space heaters in India will cause brownouts at your power plant in Florida.
Will it be mostly in the industrial sector for example?
Will it just mean more energy used in currently third world countries?
I'm saying that because, alarmism be damned, I just don't see that kind of increase in what people use electricity for. If I look at what I have around the house these days, vs what my parents had back in 75 (to use the same time interval back as what you propose forward to 2040), I'm not sure I actually use more energy than they did. E.g.,
- they had big ol' fashioned 100W lightbulbs all around the house, I have 15W CCFLs. Their (admittedly large) living room alone had 5x 100W light bulbs lighting it, I only have 2x 15W in mine.
- they had 1 fridge, I have 1 fridge. I think mine has better insulation, because, well, people discovered stuff in 30+ years.
- they had 1 washing machine, I have 1 washing machine. Theirs used a lot more power, I think. (When they bought a particular washing machine, we quickly discovered that the breakers kicked in when the washing machine's water heater, fridge and god knows what else, all kicked in.) Plus mine is rated for pretty high energy efficiency, while way back the notion wasn't even invented yet.
- for washing, there's only so much you can save, you know. (Short of stopping washing. Then again, looking at one particularly stinky co-worker... please, please, please don't. Saving the planet be damned, go take a shower;) Heating 1 litre of water by 1 degree has a lower limit on how little energy you can use, because, you know, it's just physics. Plus heating it was always as efficient as it gets: converting electricity to heat, we can do with 100% efficiency. It's only converting to other stuff that starts to be inefficient. The only thing that works differently is the insulation, and I think that's getting better too.
- they had 1 TV, I have 1 TV. You could keep the room warm with theirs, way back. Literally.
Etc.
The only thing that comes to mind as more energy used these days is my computer. Let's say that's, oh, I don't know, 200 or let's say 300W total. Just the lightbulbs in the living room cover that difference comfortably.
A polar bear is a cartesian bear after a coordinate transform.
In theory the one child per couple policy in China has been going on long enough that those children are marrying and each of those couples will be expected to look after 4 parents in later life. Worse still the couple's single child will marry and have 4 parents and 8 grandparents to worry about eventually.
I think the really big problem China will find is that because of the 1 child per family rule, they will find that there are a lot more men than women shortly. That is if they haven't already noticed. This is because for most, men at least, if they can only have one child they want a boy so they'll kill girl babies. Though I disagree with having any such law, if the Chinese wanted to reduce population pressure then what they could of done would of been to allow one boy and one girl per family. Because to maintain a stable population a birthrate of something like 2.1 or 2.6 (I've heard both) babies for each female, allowing two children would still reduce population, abet slowly.
FalconShould there be a Law?
Claim:
... guess it does look about right. Eeeep. Toss in the world population increasing roughly 50% by 2040, and the proliferation of energy-sucking technologies, and I guess the numbers make sense.
The world is on track to double its energy consumption by 2040. To reach that point in a linear fashion--not geometric one--would mean bringing on line three gigawatt class power plants every day from now until then.
So...right now we're all cumulatively using the equivalent of 36,135 gigawatt class power plants? averaging 6,022.5 watt/hrs per person per day? Lesseehere, that's about 250 watts per hour per person per planet right now - two light bulbs and a notebook computer
Just thought the numbers should get kicked around for a reality check.
Can we get a "-1 Wrong" moderation option?
The camping application usually looks for a high power to weight ratio and so is often based on thin film. The energy payback time might not be as long as you think. DARPA is sponsoring the production of 40% efficient silicon based concentrators for field applications and these will certainly have a lower payback time. But all of this is a niche application.
With regard to off-grid not being green, I think you are not looking at the whole picture. It takes greens a great deal of political effort to get the grid ammenable to net metering which does all kinds of good thing for the grid and for the environment, but utilities pushback quite hard. In many cases, excess generation over a year is not compensated, and there are ridiculously low limits on overall enrollment in some net metering programs. In 9 states, there is no net metering legislation. As the cost of solar power comes down, it is quite likely that going off grid will become more common. Now you point out that some solar generation capacity will not actually be used in this case, but this is what we should expect from cheap renewables in any case so those who go off grid will just be ahead of the curve on the ratio of generating capacity to use that we'll be arriving at in about 20 years base on 45% annual growth in renewables. You are thinking in terms of scarcity but renewable energy is fundementally abundant. It would be nice if the grid survived because it could reduce costs for storage over the long run particularly through HVDC transmission on the continent scale, but with renewable energy it does not really need to exist. The grid needs to be looking at justifications like how it might provide international stability through power sharing or how it might support very energy intensive projects by gathering together many inputs rather than its current central distribution model. It is not that renewable energy is going to be too cheap to meter, it will be cheaper but not free, but rather that the meter may become more trouble than it is worth owing to the scarcity mindset of the utlities that control it.
In summary, people who choose to reduce their environmental impact off grid are doing what they intend and while your arguments about "wasted" solar power have a sort term appeal, they are merely transition related and the huge tide of renewble energy conversion we can expect makes them pretty marginal. A person deciding to go off grid today will likely see may neighbors doing the same long before the equipment used is worn out or even comes out of warrantee. A radical change in the way utilities veiw their role might stem this, but based on experience so far, this seems unlikely.
Ovonics He gets borrowed from alot. http://en.wikipedia.org/wiki/Energy_Conversion_Devices_Ovonics Stanford Ovshinsky pioneered the field and coined the term after he founded Energy Conversion Devices, Inc. (ECD) in 1960 to further his research in amorphous semiconductors. ECD Ovonics works to create non-polluting, non-climate-changing energy sources.
Nice and insightful...
Just wondering if you were responding to the underground storage comments or the Solar Cells Flambé comments?
Not in commercial production yet but there are several competing technologies
that do at least 40%:
http://www.technologyreview.com/Energy/18910/page2/
http://www.technologyreview.com/Energy/18415/
And thank you to the commenters who have done the math: the pay back period is a fairly tricky thing to calculate even if you assume linear functions of time for efficiency decay and money costs and the KWH cost of competing sources like the power co.s
SLASHDOT: news for people who can't concentrate on work or have no life at all and got tired of yelling back at the TV.
How about using *different* generators? Like hydroelectric? Like geothermal? Like nuclear? Or do you heat your food on a plutonium pile?
Fossil fuels *must* die *now* or they will cause us great hardship real soon.
Many places can have geothermal plants. All you have to do is put pipes deep enough. Oil industry innovations can help here, I'm sure (ie. the oil rig does not only dig straight down or in straight line).
Because the record for a Cadmium Telluride cell was at approximately 16% in 2001. Six years later they are ready to manufacture a 11% efficient cell, and we're supposed to think this is progress ?
...Open Source isn't the only answer -- but it's almost always a better value than the alternatives...
AVA Solar has a facility near the intersection of I-25 & Mulberry in Fort Collins, Colorado. I know, I dropped off my resume in person. First Solar has 6 production lines in operation right now producing 60MW of panels each year and an R&D line. They have another 8 lines under construction in Malaysia, scheduled to come online in 2008. They have ~$1.5 billion USD in back orders. With all 14 production lines running it would take 3-4 years to deliver. I've toured their plant in Perrysburg, Ohio and seen the two production lines in action. It takes 3 hours from the time the pre-coated (TiO2 = transparent conductor) pre-cut 2ft by 4ft soda-lime glass panels are off-loaded to the production line till the completed solar panel modules are boxed for shipment. Most of the line is automated with robots handling the panels at strategic points along the line, otherwise it's pretty much a conveyor belt type process. The lifespan to 80% of original output is warranted to be >20 years. The 2ft by 4ft panels produce between 65-75 Watts each at the year long RMS average peak solar intensity seen at 40 degrees N latitude. The panel/module sells for about $120-$180 each. The price per Watt includes the cost of reclaiming and recycling the old panels/modules. This is why First Solar sells only to large scale installations (i.e., solar farms). CdTe and CdS, the two compounds used to create the photo diode is a much more stable compound than metallic Cd with respect to toxicity. The panels have been exposed to fires up to 1100C for several hours with very little loss of Cd. Check the First Solar website for more info. This in combination with the recycling cost/program is why they can sell in Europe. Additionally, they have 4 manufacturing lines in a plant in Dresden, Germany. The draws about CdTe/CdS is that the effective adsorption spectra is nearly perfectly in sync with the solar spectra, it only takes several microns of the polycrystalline film to adsorb ~90% of the impinging light, it works better than CIGS, amorphous Si and Si in diffuse light, it can be easily created in a non-cleanroom environment and it takes much less active material (doesn't require a wafer of Electronics grade single crystal Si) to create. The biggest drawbacks to the efficiency is the ability to capture the photo ejected electrons before electron-hole recombination occurs, the transmission and anti-reflection efficiency of the glass and TiO2, and the effect of grain boundaries on electron mobility. This is where a lot of the research is taking place, to understand the complex/non-linear nature of manufacturing the polycrystalline film versus the process control knobs. There aren't any effective simulations/models of the chemo-physical process, nor of the degradation properties of the films. That's why the yield varies so much (65Watts-75Watts) panel to panel.
The first solar panel I used was an amazing 5% efficient, so 13% is just not bad. Still, it makes me long for "Douglas-Martin Sunscreens", private space vehicles, and MY FLYING CAR!
I grew up in the '50s and '60s and read every issue of Popular Science. As they still do today, there was always an article about some cool thing that would lead to warp engines or flying cars. Reading Heinlein and Asimov further stoked me for a future with electric cars, clean sparkling cities, plenty of food for everyone, routine spaceflights to the Moon, Mars, and on out into the Belt.
Sadly, we're not even close.
No, I don't really want a flying car as the idiots with 4 wheels on the ground are terrifying enough just commuting to work. And while I do drive 30+ miles one way every weekday, flying just seems stupid. But, I do wonder if George Jetson ever really appreciated his car that folded up into a briefcase.
My feeling (*GASP*, I didn't do the math!) is that unless we go much, much, much further towards clean energy in a big hurry, we may just render this planet useless to live on. And since the warp engines (hell...our only "impulse" engine is a chemical rocket) are seemingly scarce, we don't have a lot of options on where to move humanity.
Better solar cells are certainly a step, albeit a small one, in the right direction.
I am my own gestalt.
Cadmium is a heavy metal and possibly even more dangerous then Mercury or Lead.
Cadmium Telluride is apparently even more toxic then just straight Cadmium.
Making sure these panels stay water tight so Cadmium contaminated water doesn't drip out into local ground water, as well as for manufacturing and disposal is going to be a real issue. I can just see another environmental disaster in the making if this isn't done right.
I am all for Green Technologies, but let's make sure the cure isn't worse then the problem.
J
I am always doing that which I can not do, in order that I may learn how to do it. - Pablo Picasso
Consider the modern hard disk drive. These have lifetimes measured in decades. With magnetic bearings surely we can create a decent flywheel system that can do the trick for stationary service. They won't do the trick for vehicles though because the loads are too great. I have read about "air cars" and this seems quite reasonable since the internal combustion engine is basically an air pump.
Flywheel-powered vehicles have been around for decades, and are still used in some places.
Quote: "The Basel transport authority has saved approx. 20-25% of the energy used by the trolleybus fleet fitted with flywheel accumulators compared to conventional trolleybuses on the same line. After over 10 years of use, the accumulators now average one repair/38,000 hours of operation."
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Unfortunately, the amount of money saved on electricity are quickly offset by the increase in property taxes for having solar panels in many places in the US vs. the tax breaks given in other countries.
Oh, say does that Star-Spangled Banner entwine / The myrtle of Venus with Bacchus's vine?
To calculate cost-making sense we need to know the following: The price per instant energy production and the length of time energy will be produced. You first call into question the $1 per watt value, and I that is the cost to produce. I'd expect the retail cost to be 2-3 times that as you show, so let's say $3 per watt of maximum capacity. Now how many hours will we be sunlit? Thankfully someone put out a chart for us displaying low, high, and average Sun Hours / day so we don't have to calculate based on weather data and seasons. Let's use someplace close to me, Ames, IA, with a relatively low 4.4 sun hours / day. With a $3,000 investment, that would get us 4.4 kwh/day. The typical life of most solar cells is around 20 years, so that turns out to be 32,120 kwh for a $3,000 investment, or around 9.3 cents per kilowatt hour. Pretty close to your calculations. However, this may make more sense for someone living in Las Vegas. With 6.41 average sunlit hours per day, that brings the total to 46,800 kwh over the usable life of the product, or 6.4 cents per kwh. So the price per kwh produced could be anywhere from 2.1 cents ($1 production price per watt with zero markup in Las Vegas) to 9.3 cents (200% markup and in Iowa). I currently pay 8.2 cents per kwh, so the break-even point for me would be if I could get a working unit installed for $2.60 per watt. In Las Vegas, the break-even point would be at $3.80 per watt (if their electricity costs the same as mine).
Peak energy usage hours are usually in the daytime, and when it is sunny. The main reason I believe is air conditioning and because people are at work. This could actually help to stabilize energy usage so the power companies' equipment that struggles to meet demand in the daytime isn't sitting idle at night anymore. The electric company would have instant additional unused capacity without making a capital investment and a more constant demand for energy.
You really start to notice how things were different when you look at the amount of outlets in an old house, and try to live in today's world using 6 duplex outlets in 6 rooms. Power strips and ground-lifting adapters for older ungrounded outlets become second nature in older houses.
You can say that you don't contribute to it because you don't use Glade plug-ins or have wall-warts everywhere... but that doesn't mean all of your neighbors haven't. It's just become part of society... electricity made our lives easier, right? Heh. My great-uncle tells me that it takes a lot of labor to fix that labor-saving equipment when it breaks. Sometimes I think he's more right than he knows.
-Dave
The presidents impact on the economy is pretty small, the reason that clinton's time saw a surplus was because of a Tech boom.
This argument doesn't work. The tech boom is from the 1970s when homebrewers started creating homebrew microcomputers such as the Apple and the IMSAI 8080. It really picked up when IBM released the IBM PC, then when Amiga Corporation released the Amiga and Apple released the Mac. The internet? It's the beget of Milnet which in 1983 split off of Arpanet. And Arpanet started in 1966.
Most VoIP suffered from latency issues, and other problems.
What does VoIP have to do with the boom? The tech boom was going along great before VoIP came on the scene.
The internet is still kicking, but US broadband has fallen to 16th worldwide.
Oh, I most emphatically agree. The telco incumbents are holding not just broadband but wireless braodband back. As a first step I support Google's push to have the 700mh airwaves opened. However I'd rather have the FCC abolished. The FCC was created from the Federal Radio Commission in 1934 with the passage of the Communications Act of 1934. Both were created in a period of scarcity of airwaves, however since today there is no real scarcity the FCC is not needed.
I credit the Tech Boom
I agree but the tech boom started earlier than you give credit for, see above. Clinton's as well as Newt Gingrich's fiscal policies also helped.
FalconShould there be a Law?
There are many indications that our timing systems are completely up the duff, & the fact that they’re calibrated by one another is negatively helpful.
In real (observed) life, it takes more along the line of 50-200,000 hours of burial under moist compression rather than millions of years (& the busted theories claim hundreds of millions of years) to convert organic material into petroleoids.
Likewise, diamonds can be carbon-14 dated to just a handful of thousands of years old, which represents a problem even for those who trust that the myriad assumptions which go into C-14 dating are all valid (impressive trust!).
A lot of geologic stuff only makes good sense if it could happen really quickly just like a lot of astronomical stuff only works if you do it Velikovski style.