The energy to weight ratio is about 200 times better for silicon than it is for coal in terms of required transportation infrastructure. So, solar allows development without requiring as much hardware. You probably would not transport a lot of coal by mule train, but for solar that is an option. -- Rent solar power for your home: http://mdsolar.blogspot.com/2007/01/slashdot-users -selling-solar.html
I think the variations you are seeing at the Watson house are seasonal: http://256.com/solar/graphs/kwh_prod_mon.gif. Solar panels degrade over long periods mostly owing to cosmic ray induced defects. They can be recycled though. I expect panels built today to be in service 30 years from now and on slate or tile roofs much longer. When people reshingle though, I think there will be a good chance that they will put on new panels, just for peace of mind, and it will be a toss up if the old panels end up producing somewhere else or end up getting refurbished first. I was really just winking at the joke about exponential growth. We will surely see $0.50/Watt silicon at least with refurbished stock because the energy costs will be so much lower compared to fabricating it from scratch and there is still much room for improvement of the efficiency of thin films so they may get to $0.25/Watt. That is a tenth of the cost of nuclear plant construction. As solar pushes prices for energy down, its own fabrication cost goes down so there is a bit of a virtuous circle as well.
I very much agree, there is no need for storage now. But, the question I was responding to was how do other sources of electricity moderate the growth of solar power (22 years to replace net generation). We may not need it (other than what hydro can provide) but if it is cheaper than even wind we'll likely use it. In some ways, with electric transportation, there will be storage from the degraded but still usable batteries which I think will be used regardless of cost because they will be made anyway.
Wow, that is about the least accurate thing I've seen. Not even within an order of magnitude. Their other numbers appear to be fabricated as well. Hope Beller is out of work because you don't want to be anywhere near anything he's been involved in.
You are looking at retail prices which are all silicon. There has been a raw material shortage for these and demand has been high. Wholesale, and especially thin film panels are much less expensive but these don't get used on homes much. The issue with silicon in mentioned in the article.
-- Rent solar power and save: http://mdsolar.blogspot.com/2007/01/slashdot-users -selling-solar.html
The cells do degrade mostly owing to cosmic rays creating defects in the doping layer. So, they'll perform to better than 80% over 25 years. In 100
years they'll degrade to 40%. You get about 66 effective new years in a century. Cells can be recycled: http://www.solarworld.de/solarmaterial/english/pre ss/8AV.3.14.pdf at about a third of the cost in energy to make them originally. Used in a location that give an energy returned on energy invested (EROEI) of 33 for extended life panels (two years payback), the recycled panels will have EROEI of 99. This is higher than any other energy source. -- Rent solar power: http://mdsolar.blogspot.com/2007/01/slashdot-users -selling-solar.html
I've been having a discussion with Chuck DeVore who is in the California Assembly: http://mdsolar.blogspot.com/2007/08/what-dormouse- said.html. He is very pro-nuke and anti-solar. One thing that has come up is the Pacific Intertie which carries power from the Northwest to LA. He points out that the
Northwest is growing and may not have power to send in the future. That is where he comes from originally. If that future includes solar, then the power might flow in the other direction. I don't think I've persuaded him yet, but it is a very impressive piece of hardware: http://en.wikipedia.org/wiki/Pacific_DC_Intertie. -- Rent solar power with no installation cost: http://mdsolar.blogspot.com/2007/01/slashdot-users -selling-solar.html
It depends on two things. The cost of solar and the cost of storage. If the cost of solar gets cheaper than everything else but the cost of storage makes the combination more expensive than some we'll likely see hydro getting more generation capacity and used less frequently (at night) because this
is effective storage and some other night time sources will be used, likely wind since it is the cheapest now. If storage gets cheap enough to have the
combination lower than other methods of generation, then the others will retire though I'd think flood control would still leave some hydro. -- Rent solar power: http://mdsolar.blogspot.com/2007/01/slashdot-users -selling-solar.html
You forgot to account for panels that wear out I think. Still what is 7th decimal place among freinds. Depending on the cost of storage, producing enough solar power to handle use at say 5 PM in the spring and just discard some of the noon generation. Just add a couple more years of production. -- Rent solar power and save: http://mdsolar.blogspot.com/2007/01/slashdot-users -selling-solar.html
First Solar's panels are only available to commercial installers. $1.19/Watt is what it cost them to make, but the sell at over $2/Watt. And, no one is quite sure yet how long they last though they are doing quite a lot of work with NREL to get that nailed down. They want for them to last 20 years. So,
if you could buy at cost and you were happy with DC when the sun shines, assuming 5 hours average peak equivilent sun light per day you cost for that electricity would be about 3.3 cents per kWh. Inverters cost about $0.9/Watt assuming you want 20 years out of them. If you could get the panels, you
would mount them in a yard because they are not that efficient so your roof would be too small but that means that your installation cost would be low.
You can certainly beat 15 cents per kWh though. -- Rent solar power and save: http://mdsolar.blogspot.com/2007/01/slashdot-users -selling-solar.html
There were 1.7 GW installed in 2006: http://www.solarbuzz.com/Marketbuzz2007-intro.htm bringing the world up to about 6 GW. At a typical 5 hours
per day equivilent peak generation that comes to 11 billion kWh per year. World net generation was 16,590.6 billion kWh per year in 2004: http://www.eia.doe.gov/emeu/aer/txt/ptb1116.html, so your fraction should be 0.07%, off by about 4 orders of magnitude. At 45% growth, how long would it take to replace world net generation? Somewhat less that 22 years since 1.45^22=3550 which would imply that more than half of the worlds net generation would be fabricated in the year 2028, with the rest fabricated prior to that year. Since panels last 25 years or longer there would have been
little need to replace existing solar PV capacity by that time. -- Rent residential solar power: http://mdsolar.blogspot.com/2007/01/slashdot-users -selling-solar.html
Under GR, the effect of mass in the medium is to change the geodesic but this is achromatic. Are you thinking of electromagnetic effects that change the index of refraction as a function of wavelength? -- Rent residential solar power: http://mdsolar.blogspot.com/2007/01/slashdot-users -selling-solar.html
These are some interesting issues. Weather stations are a pretty old technology people have been checking data quality for quite some time. The more advanced areas I was thinking of were more along the lines of trying to understand why models underpredict sea level rise. I could be that weather stations and satellites are under reporting temperatures but more likely it is that models of glacial melting are too simple and do not capture accelerated flows owing to enhanced lubrication from surface meltwater that bores down to the base.
One thing that might be done is to keep a record of temperatures at your home and try to compare this with stations in the network that are close to you. This might reveal systematic drifts that might be tied to the sorts of conditions you are worried about. Another effort might be to reproduce a station and then attempt to affect its operation in different ways. This would likely reproduce early calibration work but it would be good to have an independent effort. One old temperature record that seems sound was provided by Benjamin Franklin. He measured the Gulf Stream temperature on a couple of voyages: http://www.nha.org/history/hn/HN-v44n2-gulfstream. htm. The records used in the warming charts don't go as far back as this but may have been obtained with similar care.
Except for mine, where the grass won't grow, I notice I can usually tell how the drain field is laid out by the color of the grass. Probably won't be long before a remote sensing system can manage to figure out what special fertilizers are involved. It would be kind of like those science projects with caffeine and bean seeds. You're next.... -- Rent solar power: http://mdsolar.blogspot.com/2007/01/slashdot-users -selling-solar.html
Solar is currently competitive as distrubuted generation, displacing delivered central generation. It is also developing rapidly in the southwest as central generation, displacing gas. You'll notice wind does not appear in your link either yet wind development in PA is pretty spectacular. You're link may not be the best guide to what is happening. Your number for nuclear power seems low but what is important here is the future cost. You may want to look at table 39 here: http://www.eia.doe.gov/oiaf/aeo/assumption/pdf/ele ctricity.pdf#page=3 keeping track of online years. Nuclear does pretty poorly. Assuming solar beats wind in ten years (and wind continues its decent) nuclear is going to be at the top of pricing.
Slashdot Mirror
The energy to weight ratio is about 200 times better for silicon than it is for coal in terms of required transportation infrastructure. So, solar allows development without requiring as much hardware. You probably would not transport a lot of coal by mule train, but for solar that is an option.s -selling-solar.html
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Rent solar power for your home: http://mdsolar.blogspot.com/2007/01/slashdot-user
HVDC lines are built to last so corrosion is one of the things considered. If solar power is truely cheap, more line loss will be acceptable. It seems to me that truly high capacity lines will have less line loss for a couple of reasons: http://mdsolar.blogspot.com/2007/03/coast-to-coast .html. So, a worldwide web of transmission could make a lot of sense.s -selling-solar.html
--
Rent solar power: http://mdsolar.blogspot.com/2007/01/slashdot-user
I think the variations you are seeing at the Watson house are seasonal: http://256.com/solar/graphs/kwh_prod_mon.gif. Solar panels degrade over long periods mostly owing to cosmic ray induced defects. They can be recycled though. I expect panels built today to be in service 30 years from now and on slate or tile roofs much longer. When people reshingle though, I think there will be a good chance that they will put on new panels, just for peace of mind, and it will be a toss up if the old panels end up producing somewhere else or end up getting refurbished first. I was really just winking at the joke about exponential growth. We will surely see $0.50/Watt silicon at least with refurbished stock because the energy costs will be so much lower compared to fabricating it from scratch and there is still much room for improvement of the efficiency of thin films so they may get to $0.25/Watt. That is a tenth of the cost of nuclear plant construction. As solar pushes prices for energy down, its own fabrication cost goes down so there is a bit of a virtuous circle as well.
I very much agree, there is no need for storage now. But, the question I was responding to was how do other sources of electricity moderate the growth of solar power (22 years to replace net generation). We may not need it (other than what hydro can provide) but if it is cheaper than even wind we'll likely use it. In some ways, with electric transportation, there will be storage from the degraded but still usable batteries which I think will be used regardless of cost because they will be made anyway.
Wow, that is about the least accurate thing I've seen. Not even within an order of magnitude. Their other numbers appear to be fabricated as well. Hope Beller is out of work because you don't want to be anywhere near anything he's been involved in.
You are looking at retail prices which are all silicon. There has been a raw material shortage for these and demand has been high. Wholesale, and especially thin film panels are much less expensive but these don't get used on homes much. The issue with silicon in mentioned in the article.s -selling-solar.html
--
Rent solar power and save: http://mdsolar.blogspot.com/2007/01/slashdot-user
Yes, there is a project in New Mexico to do just this linked here: http://mdsolar.blogspot.com/2007/07/new-mexicans-c onspire.html. s -selling-solar.html
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Solar power at home: http://mdsolar.blogspot.com/2007/01/slashdot-user
The cells do degrade mostly owing to cosmic rays creating defects in the doping layer. So, they'll perform to better than 80% over 25 years. In 100 years they'll degrade to 40%. You get about 66 effective new years in a century. Cells can be recycled: http://www.solarworld.de/solarmaterial/english/pre ss/8AV.3.14.pdf at about a third of the cost in energy to make them originally. Used in a location that give an energy returned on energy invested (EROEI) of 33 for extended life panels (two years payback), the recycled panels will have EROEI of 99. This is higher than any other energy source.s -selling-solar.html
--
Rent solar power: http://mdsolar.blogspot.com/2007/01/slashdot-user
I've been having a discussion with Chuck DeVore who is in the California Assembly: http://mdsolar.blogspot.com/2007/08/what-dormouse- said.html. He is very pro-nuke and anti-solar. One thing that has come up is the Pacific Intertie which carries power from the Northwest to LA. He points out that the
Northwest is growing and may not have power to send in the future. That is where he comes from originally. If that future includes solar, then the power might flow in the other direction. I don't think I've persuaded him yet, but it is a very impressive piece of hardware: http://en.wikipedia.org/wiki/Pacific_DC_Intertie. s -selling-solar.html
--
Rent solar power with no installation cost: http://mdsolar.blogspot.com/2007/01/slashdot-user
You slipped the units. That should be 4.32 kWh/day. But, you also for got to tilt the panels: http://www.nrel.gov/gis/images/us_pv_annual_may200 4.jpg. You want 5 kWh per meter^2 per day and at 17% system efficiency that is about 0.85 kWh/m^2/day. You need 39 m^2 of panels to get 33 kWh/day or about 6 meters on a side.s -selling-solar.html
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Rent solar power and save: http://mdsolar.blogspot.com/2007/01/slashdot-user
The cost of fuel cells is similar to solar http://www.eia.doe.gov/oiaf/aeo/assumption/pdf/ele ctricity.pdf#page=3 but is not falling as fast. Do you have a reference for the conversion efficiency for the algae? Current silicon PV gets close to 20% and 40% cells are expected to be in production in 3 years as a result of a DARPA initiative. s -selling-solar.html
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Solar power saves money: http://mdsolar.blogspot.com/2007/01/slashdot-user
It depends on two things. The cost of solar and the cost of storage. If the cost of solar gets cheaper than everything else but the cost of storage makes the combination more expensive than some we'll likely see hydro getting more generation capacity and used less frequently (at night) because this is effective storage and some other night time sources will be used, likely wind since it is the cheapest now. If storage gets cheap enough to have the combination lower than other methods of generation, then the others will retire though I'd think flood control would still leave some hydro.s -selling-solar.html
--
Rent solar power: http://mdsolar.blogspot.com/2007/01/slashdot-user
You forgot to account for panels that wear out I think. Still what is 7th decimal place among freinds. Depending on the cost of storage, producing enough solar power to handle use at say 5 PM in the spring and just discard some of the noon generation. Just add a couple more years of production.s -selling-solar.html
--
Rent solar power and save: http://mdsolar.blogspot.com/2007/01/slashdot-user
Actually, the algae are not quite as efficent as current solar cells http://mdsolar.blogspot.com/2007/02/photosynthesis .html and you later lose about 60% of the energy when you burn the biofuels since internal combustion engines are not very efficient.s -selling-solar.html
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Solar! It's what's for power: http://mdsolar.blogspot.com/2007/01/slashdot-user
At current system efficiencies (17%) residential rooftops can supply 46% of net generation. That is more that the residential sector consumes. http://mdsolar.blogspot.com/2007/08/roof-pitch.htm l. Land
area is not really an issue with solar.s -selling-solar.html
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Rent solar power with no installation charge: http://mdsolar.blogspot.com/2007/01/slashdot-user
First Solar's panels are only available to commercial installers. $1.19/Watt is what it cost them to make, but the sell at over $2/Watt. And, no one is quite sure yet how long they last though they are doing quite a lot of work with NREL to get that nailed down. They want for them to last 20 years. So, if you could buy at cost and you were happy with DC when the sun shines, assuming 5 hours average peak equivilent sun light per day you cost for that electricity would be about 3.3 cents per kWh. Inverters cost about $0.9/Watt assuming you want 20 years out of them. If you could get the panels, you would mount them in a yard because they are not that efficient so your roof would be too small but that means that your installation cost would be low. You can certainly beat 15 cents per kWh though.s -selling-solar.html
--
Rent solar power and save: http://mdsolar.blogspot.com/2007/01/slashdot-user
Could not resist this: http://webexhibits.org/daylightsaving/franklin3.ht ml s -selling-solar.html
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Solar power for what you pay now: http://mdsolar.blogspot.com/2007/01/slashdot-user
I came across an interesting article explaning how California utility PG&E is entering into a contract to obtian used batteries from electric cars: http://money.cnn.com/magazines/business2/business2 _archive/2007/08/01/100138830/index.htm. They'll use these for stationary storage. If the
current fleet is converted to electric, I calculate that these used batteries can store about half a day of our energy use: http://mdsolar.blogspot.com/2007/08/roof-pitch.htm l. That does not cover seasonal variations in solar power, but it does look more like getting
base load as well as peak from solar.s -selling-solar.html
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Save money by renting solar power: http://mdsolar.blogspot.com/2007/01/slashdot-user
There were 1.7 GW installed in 2006: http://www.solarbuzz.com/Marketbuzz2007-intro.htm bringing the world up to about 6 GW. At a typical 5 hours per day equivilent peak generation that comes to 11 billion kWh per year. World net generation was 16,590.6 billion kWh per year in 2004: http://www.eia.doe.gov/emeu/aer/txt/ptb1116.html, so your fraction should be 0.07%, off by about 4 orders of magnitude. At 45% growth, how long would it take to replace world net generation? Somewhat less that 22 years since 1.45^22=3550 which would imply that more than half of the worlds net generation would be fabricated in the year 2028, with the rest fabricated prior to that year. Since panels last 25 years or longer there would have been little need to replace existing solar PV capacity by that time.s -selling-solar.html
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Rent residential solar power: http://mdsolar.blogspot.com/2007/01/slashdot-user
You are mistaken that quality checks are not performed. Read this: http://www.ncdc.noaa.gov/oa/climate/research/ushcn /hcntmptrends.php. I think that the other efforts you mention will confirm the soundness of the data for the purpose for which it is used.
Under GR, the effect of mass in the medium is to change the geodesic but this is achromatic. Are you thinking of electromagnetic effects that change the index of refraction as a function of wavelength?s -selling-solar.html
--
Rent residential solar power: http://mdsolar.blogspot.com/2007/01/slashdot-user
These are some interesting issues. Weather stations are a pretty old technology people have been checking data quality for quite some time. The more advanced areas I was thinking of were more along the lines of trying to understand why models underpredict sea level rise. I could be that weather stations and satellites are under reporting temperatures but more likely it is that models of glacial melting are too simple and do not capture accelerated flows owing to enhanced lubrication from surface meltwater that bores down to the base.
. htm. The records used in the warming charts don't go as far back as this but may have been obtained with similar care.
One thing that might be done is to keep a record of temperatures at your home and try to compare this with stations in the network that are close to you. This might reveal systematic drifts that might be tied to the sorts of conditions you are worried about. Another effort might be to reproduce a station and then attempt to affect its operation in different ways. This would likely reproduce early calibration work but it would be good to have an independent effort. One old temperature record that seems sound was provided by Benjamin Franklin. He measured the Gulf Stream temperature on a couple of voyages: http://www.nha.org/history/hn/HN-v44n2-gulfstream
So either that or Ozzie and Harriet...s -selling-solar.html
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Groan for solar power: http://mdsolar.blogspot.com/2007/01/slashdot-user
Except for mine, where the grass won't grow, I notice I can usually tell how the drain field is laid out by the color of the grass. Probably won't be long before a remote sensing system can manage to figure out what special fertilizers are involved. It would be kind of like those science projects with caffeine and bean seeds. You're next....s -selling-solar.html
--
Rent solar power: http://mdsolar.blogspot.com/2007/01/slashdot-user
Solar is currently competitive as distrubuted generation, displacing delivered central generation. It is also developing rapidly in the southwest as central generation, displacing gas. You'll notice wind does not appear in your link either yet wind development in PA is pretty spectacular. You're link may not be the best guide to what is happening. Your number for nuclear power seems low but what is important here is the future cost. You may want to look at table 39 here: http://www.eia.doe.gov/oiaf/aeo/assumption/pdf/ele ctricity.pdf#page=3 keeping track of online years. Nuclear does pretty poorly. Assuming solar beats wind in ten years (and wind continues its decent) nuclear is going to be at the top of pricing.