Post by thread:[EE]: solar farm on 10 / 100 square miles

So you are saying 10 miles square, which is 100 square miles ? cc {Quote hidden}> > On Mar 16, 2008, at 6:23 PM, Bob Axtell wrote: > > Cedric Chang wrote: >> Someone said they had a link to a proposal to use 10 or 100 square >> miles of sunny desert land to make hydrogen and oxygen from water and >> solar energy. Can anyone direct me to this proposed solar farm ? >> >> I want to run the numbers on acquiring land down south ( USA ) and >> what the technology costs would be. >> >> cc >> >> >> > I can't find the original book I saw those figures in, sorry. It was a > good book, about 15 years > ago, can't locate it now. But I remember after reading it that I > did the > math, and 10miles square > indeed did the job nicely, with energy left over, even with the sun > going down every night. > > --Bob Axtell >

Yep. Cedric Chang wrote: {Quote hidden}> So you are saying 10 miles square, which is 100 square miles ? > cc > > >> On Mar 16, 2008, at 6:23 PM, Bob Axtell wrote: >> >> Cedric Chang wrote: >> >>> Someone said they had a link to a proposal to use 10 or 100 square >>> miles of sunny desert land to make hydrogen and oxygen from water and >>> solar energy. Can anyone direct me to this proposed solar farm ? >>> >>> I want to run the numbers on acquiring land down south ( USA ) and >>> what the technology costs would be. >>> >>> cc >>> >>> >>> >>> >> I can't find the original book I saw those figures in, sorry. It was a >> good book, about 15 years >> ago, can't locate it now. But I remember after reading it that I >> did the >> math, and 10miles square >> indeed did the job nicely, with energy left over, even with the sun >> going down every night. >> >> --Bob Axtell >> >>

Paul Hutchinson wrote: > I found a pro-solar energy web site that claims: > "Covering 9% of Nevada with parabolic trough systems could generate enough > electrical power for the whole of the USA." > http://www.power-technology.com/projects/sanfrancisco/ See final paragraph. > > Nevada is a bit over 110,000 square miles in size. This would make it around > 10,000 square miles of land to power the US. > > Paul Hutch > > Nevada has less sunlight than So Arizona. But this size is huge, compared to what it really takes to do this. I think this is dramatically incorrect. But the verbiage is otherwise correct; the parabolic trough systems can concentrate the sunlight to the working medium almost ideally. Nevertheless, the problem isn't generating the energy...that's a piece of cake, really...the problem is moving the electricity to where it is needed, which cannot be done with the grid system we have now...and this fiscal crisis will take at least a decade to wash out, so I can't see anything happening to fix it in my lifetime... The advantage of Arizona is that the state is mostly Indian reservations, who would appreciate getting the chance to lease some of their useless land. Also, the Indian populations are all incredibly low- almost nobody lives there- even the tree huggers would have a tough time getting wound up over the idea, so it would bring welcome jobs... --Bob Axtell >> {Original Message removed}

David VanHorn wrote: >>> Well, we do have >1% of our population in prison. >> >> So to keep the labor force close, build the prisons under the solar >> farms. Perfect! > > not a sucky idea actually.. I do like the idea of those guys doing > something productive. I can see the law enforcement guidelines after this is implemented... "Our mirrors are dirty; we need more workers. Your target for this quarter is twenty court-confirmed prison man-years per officer per month. Whoever stays below that, needs to look for another job; this is no place for sissies. I'm not really saying that you should tamper evidence, but you should definitely look at your future with the force." :) Gerhard

> -----Original Message----- > From: piclist-bouncesKILLspammit.edu On Behalf Of Bob Axtell > Sent: Monday, March 17, 2008 1:03 PM > > Nevada has less sunlight than So Arizona. But this size is huge, Reference please. A reference I found, National Renewable Energy Laboratory (NREL), does not appear to support that statement. It looks to me like southern Nevada has more potential solar energy than any other area of the USA. This makes sense for why the pro-solar organization would choose Nevada for its statement over Arizona. Direct Normal Solar Radiation (Two-Axis Tracking Concentrator) annual: www.nrel.gov/gis/images/us_csp_annual_may2004.jpg Main page http://www.nrel.gov/gis/solar.html Frankly since you have provided no references for either of your assertions it seems you are just making this stuff up out of thin air. Perhaps the book(s) you saw the information in were just totally wrong. 10,000 sq. mi. vs. 100 sq. mi. is an extremely significant discrepancy. With no references to the 100 sq. mi. version I can't consider it even remotely matching reality. Hand waving away referenced statements and changing the subject doesn't count when trying to determine the reality of a situation. Paul Hutch {Quote hidden}> compared to what it really takes to do this. > I think this is dramatically incorrect. But the verbiage is otherwise > correct; the parabolic trough systems can > concentrate the sunlight to the working medium almost ideally. > > Nevertheless, the problem isn't generating the energy...that's a piece > of cake, really...the problem is moving the > electricity to where it is needed, which cannot be done with the grid > system we have now...and this fiscal crisis > will take at least a decade to wash out, so I can't see anything > happening to fix it in my lifetime... > > The advantage of Arizona is that the state is mostly Indian > reservations, who would appreciate getting the chance > to lease some of their useless land. Also, the Indian populations are > all incredibly low- almost nobody lives there- > even the tree huggers would have a tough time getting wound up over the > idea, so it would bring welcome jobs... > > --Bob Axtell

Paul Hutchinson wrote: {Quote hidden}>> -----Original Message----- >> From: .....piclist-bouncesKILLspam.....mit.edu On Behalf Of Bob Axtell >> Sent: Monday, March 17, 2008 1:03 PM >> >> Nevada has less sunlight than So Arizona. But this size is huge, >> > > Reference please. > > A reference I found, National Renewable Energy Laboratory (NREL), does not > appear to support that statement. It looks to me like southern Nevada has > more potential solar energy than any other area of the USA. This makes sense > for why the pro-solar organization would choose Nevada for its statement > over Arizona. > Direct Normal Solar Radiation (Two-Axis Tracking Concentrator) annual: > www.nrel.gov/gis/images/us_csp_annual_may2004.jpg > Main page > http://www.nrel.gov/gis/solar.html > > Frankly since you have provided no references for either of your assertions > it seems you are just making this stuff up out of thin air. Perhaps the > book(s) you saw the information in were just totally wrong. 10,000 sq. mi. > vs. 100 sq. mi. is an extremely significant discrepancy. With no references > to the 100 sq. mi. version I can't consider it even remotely matching > reality. Hand waving away referenced statements and changing the subject > doesn't count when trying to determine the reality of a situation. > > Paul Hutch > > >> compared to what it really takes to do this. >> I think this is dramatically incorrect. But the verbiage is otherwise >> correct; the parabolic trough systems can >> concentrate the sunlight to the working medium almost ideally. >> >> Nevertheless, the problem isn't generating the energy...that's a piece >> of cake, really...the problem is moving the >> electricity to where it is needed, which cannot be done with the grid >> system we have now...and this fiscal crisis >> will take at least a decade to wash out, so I can't see anything >> happening to fix it in my lifetime... >> >> The advantage of Arizona is that the state is mostly Indian >> reservations, who would appreciate getting the chance >> to lease some of their useless land. Also, the Indian populations are >> all incredibly low- almost nobody lives there- >> even the tree huggers would have a tough time getting wound up over the >> idea, so it would bring welcome jobs... >> >> --Bob Axtell >> > > OK, I'll work on it as soon as I can. I didn't make any of this up; no need to, since I won't be able to do the work on it anyway; it will be you young guys.Your links look good, BTW. --BobA

> OK, I'll work on it as soon as I can. I didn't make any of > this up; no > need to, since I won't be able > to do the work on it anyway; it will be you young > guys.Your links look > good, BTW. Postscript: According to http://upload.wikimedia.org/wikipedia/commons/4/4e/USEnFlow02-quads.gif only about 38% of energy input in the US systems results in "useful energy" :-(. _____________ An amazingly polite answer, I thought, considering :-) Lets try again as I think someone has already done. With Cedric's benison I'll start off in imperial and translate to metric somewhere along the way. if we crash on Olympus Mons you'll know what happened. 1 square mile is (1600 metres) ^2 m^2 = 2,560,000 m^2. Say 2.5E6 m^2. Assume 1 standard sun = 1000 W/m^2 (which it is) Assume 15% energy conversion. Assume (without looking at insolation maps) 5 kWh/m^2/day mean. Assume 50% loss from source to sink. Available energy per annum per square mile is: 2.5E6 m^2 x 1000 W x 15% * 50% * 5 hrs/day x 365 days ~= 6.8E11 Watt.hours = 6.8E8 kW.h = 6.8E5 MW.h / mile^2 For 100,000 square miles thats about 7E10 MW.h/year or 7E5 TW.h/year Turning that back into a power figure that's 7E5/8765 ~= 80 TW = 80 TerraWatt. Average US usage in 2005 was about 3.3 TW http://en.wikipedia.org/wiki/Energy_use_in_the_United_States so if my above figures are correct (which is highly unlikely) we could get by on say 4/80 or 5% of the above area. Double this to 10% for inefficient area utilisation (which I had meant to include) to get 10%. = 1000 square miles or about 30 miles x 30 miles. By all means revisit my assumptions and find my [purposeful [tm]] errors and report back. Doing it would be the hard part :-). 15% is about as good as the best realistic single junction solar arrays. They'll get better and other means will give them a run for their money so I think 15% is not too bad a guesstimate. Russell McMahon

Apptech wrote: {Quote hidden}>> OK, I'll work on it as soon as I can. I didn't make >> > any of > >> this up; no >> need to, since I won't be able >> to do the work on it anyway; it will be you young >> guys.Your links look >> good, BTW. >> > > Postscript: > > According to > http://upload.wikimedia.org/wikipedia/commons/4/4e/USEnFlow02-quads.gif > > only about 38% of energy input in the US systems results in > "useful energy" :-(. > > _____________ > > An amazingly polite answer, I thought, considering :-) > > Lets try again as I think someone has already done. With > Cedric's benison I'll start off in imperial and translate to > metric somewhere along the way. if we crash on Olympus Mons > you'll know what happened. > > 1 square mile is (1600 metres) ^2 m^2 = 2,560,000 m^2. > Say 2.5E6 m^2. > Assume 1 standard sun = 1000 W/m^2 (which it is) > Assume 15% energy conversion. > Assume (without looking at insolation maps) 5 kWh/m^2/day > mean. > Assume 50% loss from source to sink. > Available energy per annum per square mile is: > > 2.5E6 m^2 x 1000 W x 15% * 50% * 5 hrs/day x 365 days > > ~= 6.8E11 Watt.hours > = 6.8E8 kW.h > = 6.8E5 MW.h / mile^2 > > For 100,000 square miles thats about > > 7E10 MW.h/year > or 7E5 TW.h/year > > Turning that back into a power figure that's > > 7E5/8765 > ~= 80 TW = 80 TerraWatt. > > Average US usage in 2005 was about 3.3 TW > > http://en.wikipedia.org/wiki/Energy_use_in_the_United_States > > so if my above figures are correct (which is highly > unlikely) we could get by on say 4/80 or 5% of the above > area. > > Double this to 10% for inefficient area utilisation (which I > had meant to include) to get 10%. > = 1000 square miles or about 30 miles x 30 miles. > > By all means revisit my assumptions and find my [purposeful > [tm]] errors and report back. > > Doing it would be the hard part :-). > > 15% is about as good as the best realistic single junction > solar arrays. They'll get better and other means will give > them a run for their money so I think 15% is not too bad a > guesstimate. > > > Actually, I had no plan to use PV arrays, but to concentrate the sunlight and use standard heat engines (Stirling, steam, et ) although, as stated, PV cells are being improved all the time. --Bob > > > Russell McMahon > >

>> 15% is about as good as the best realistic single >> junction >> solar arrays. They'll get better and other means will >> give >> them a run for their money so I think 15% is not too bad >> a >> guesstimate. > Actually, I had no plan to use PV arrays, but to > concentrate the > sunlight and use standard > heat engines (Stirling, steam, et ) although, as stated, > PV cells are > being improved all the > time. Yes. I used PV as a benchmark as it's much easier to get current costings and efficiencies for them and they price is falling nicely and should continue to do so for some time. As noted "other means will give them a run for their money" - I'm a Stirling aficionado but don't think that they yet have a real world place at this sort of scale, alas. In time they should. Steam and similar (water or exotic fluids) is done currently at scale in the largest systems installed so far, but the mechanical challenges at the energy levels involved and the mature nature of the underlying technology (if not the actual implementation) may mean that if PV prices continue to fall as they are doing now then the mechanical systems will become less competitive. Stirling systems should be able to double current PV percentages*, but one can expect PV percentages to double in the next decade while Stirling would be very hardput to scale up similarly to stay ahead of them (the laws of Physics being an unkind master). Also, PV advances in continuous sheet processes may see vastly cheaper cost per Watt at lower than current efficiencies, or even at around current efficiencies. Stirling would be doing well in practice to get over say 50% Carnot, although some specialist systems do. At say 350 K cold sink and 1050 K hot, Carnot efficiency is 66% so 50% of this is 30%+. Running the hot side to 1400 K (1100C) gives a 75% Carnot efficiency but invites extreme engineering problems. Russell

Apptech wrote: > Lets try again as I think someone has already done. With Cedric's benison > I'll start off in imperial and translate to metric somewhere along the > way. if we crash on Olympus Mons you'll know what happened. > 1 square mile is (1600 metres) ^2 m^2 = 2,560,000 m^2. > Say 2.5E6 m^2. > Assume 1 standard sun = 1000 W/m^2 (which it is) > Assume 15% energy conversion. > Assume (without looking at insolation maps) 5 kWh/m^2/day > mean. > Assume 50% loss from source to sink. > Available energy per annum per square mile is: > > 2.5E6 m^2 x 1000 W x 15% * 50% * 5 hrs/day x 365 days > > ~= 6.8E11 Watt.hours Fixing the units (which is especially important when using non-SI units -- we all know why :) and using the insolation figure, I get: ((1600 m)^2)/sqmi * 5 kWh/m^2/day * 365 day/year * 0.15 * 0.5 = 350e6 kWh/sqmi/year = 350 GWh/sqmi/year > For 100,000 square miles thats about > > 7E10 MW.h/year > or 7E5 TW.h/year (7e10 M = 7e5 T ? :) Here I get: 350 GWh/sqmi/year * 100'000 sqmi = 350e5 GWh/year = 35e3 TWh/year > 7E5/8765 > ~= 80 TW = 80 TerraWatt. Again, using proper units: (35e3 TWh/year) / (8765 h/year) = 4 TW Which somewhat (but not substantially) affects the conclusions. This just for an example of a procedure that helps avoiding unit errors: Put the units in the calculation, not in the text. The unit calculation must also work out -- if it doesn't, there's somewhere an error. Gerhard

Last night I was reading this weeks EETimes and found it has an article on the seventeenth annual Photovoltaic Science and Engineering Conference. http://www.eetimes.com/news/design/showArticle.jhtml;?articleID=206902796 A quote relevant to this topic: "In fact, a solar array 150 x 150 km could, in principle, meet all of North America's energy needs. But PV technology is still more expensive than grid power, lacks a suitable load-balancing solution and requires considerable space for electricity generation." If I've done the conversion factor correctly that's 9000 square miles. That's 10% less area than the old 2002 article I found earlier had proposed. Paul Hutch > {Original Message removed}

Without delving too much in to the realm of politics, I would like to point out that if you took the cost of the Iraq war ($3 trillion when you take in to account the future interest payments and care of veterans, infrastructure costs, etc.) you could probably build a number of these solar farms and export power to the rest of the world! ----- A quote relevant to this topic: "In fact, a solar array 150 x 150 km could, in principle, meet all of North America's energy needs. But PV technology is still more expensive than grid power, lacks a suitable load-balancing solution and requires considerable space for electricity generation." If I've done the conversion factor correctly that's 9000 square miles. That's 10% less area than the old 2002 article I found earlier had proposed. {Quote hidden}> > so if my above figures are correct (which is highly > unlikely) we could get by on say 4/80 or 5% of the above > area. > > Double this to 10% for inefficient area utilisation (which I > had meant to include) to get 10%. > = 1000 square miles or about 30 miles x 30 miles. > > By all means revisit my assumptions and find my [purposeful > [tm]] errors and report back. > > Doing it would be the hard part :-). > > 15% is about as good as the best realistic single junction > solar arrays. They'll get better and other means will give > them a run for their money so I think 15% is not too bad a > guesstimate. > > > > > > Russell McMahon

Hmmm... without delving too much in to politics either, it would be possible with $3T to produce a few around the world that were strategically placed (nevada, sahara, etc.) such that as one region experiences a sun set the next region is coming online.... with some smart energy management it may be possible to distribute the energy worldwide as required and not have to come up with some serious energy buffering strategies that local geography would require. Somehow I don't think the current international 'political climate' will allow for 'certain' countries to maintain a localized control of the energy resources for the rest of the world.... unless that country is the US, of course.... meet the OPEC's future sibling, the OSEEC (Organisation of Solar Energy Exporting Countries). Rolf Mike Reid wrote: {Quote hidden}> Without delving too much in to the realm of politics, I would like to point > out that if you took the cost of the Iraq war ($3 trillion when you take in > to account the future interest payments and care of veterans, infrastructure > costs, etc.) you could probably build a number of these solar farms and > export power to the rest of the world! > > ----- > > A quote relevant to this topic: > > "In fact, a solar array 150 x 150 km could, in principle, meet all of North > America's energy needs. But PV technology is still more expensive than grid > power, lacks a suitable load-balancing solution and requires considerable > space for electricity generation." > > If I've done the conversion factor correctly that's 9000 square miles. > That's 10% less area than the old 2002 article I found earlier had proposed. > > >> so if my above figures are correct (which is highly >> unlikely) we could get by on say 4/80 or 5% of the above >> area. >> >> Double this to 10% for inefficient area utilisation (which I >> had meant to include) to get 10%. >> = 1000 square miles or about 30 miles x 30 miles. >> >> By all means revisit my assumptions and find my [purposeful >> [tm]] errors and report back. >> >> Doing it would be the hard part :-). >> >> 15% is about as good as the best realistic single junction >> solar arrays. They'll get better and other means will give >> them a run for their money so I think 15% is not too bad a >> guesstimate. >> >> >> >> >> >> Russell McMahon >> > >

> ... if you took the cost of the Iraq war ($3 trillion when you take in to account the future interest payments and care of veterans, infrastructure costs, etc.) you could probably build a number of these solar farms and export power to the rest of the world! At $1/watt $3 terabucks would noticeably undershoot current US consumption. On the bright side, 3 trillion seems pretty optimistic - I remember the economic prognostication about our SEA adventure back in the day - Around $150 billion would cover it, thought the wise men... Hell, I personally have cost the govt over $1 M in medical & related costs since then, and that tab is still running , thank you very much :) I like the idea of spending our mad money on Solar instead. Jack us (SEA vets). Jack On 3/18/08, Rolf <EraseMElearrspam_OUTTakeThisOuTrogers.com> wrote: {Quote hidden}> Hmmm... > without delving too much in to politics either, it would be possible > with $3T to produce a few around the world that were strategically > placed (nevada, sahara, etc.) such that as one region experiences a sun > set the next region is coming online.... with some smart energy > management it may be possible to distribute the energy worldwide as > required and not have to come up with some serious energy buffering > strategies that local geography would require. > > Somehow I don't think the current international 'political climate' will > allow for 'certain' countries to maintain a localized control of the > energy resources for the rest of the world.... unless that country is > the US, of course.... meet the OPEC's future sibling, the OSEEC > (Organisation of Solar Energy Exporting Countries). > > Rolf > > > Mike Reid wrote: > > Without delving too much in to the realm of politics, I would like to > point > > out that if you took the cost of the Iraq war ($3 trillion when you take > in > > to account the future interest payments and care of veterans, > infrastructure > > costs, etc.) you could probably build a number of these solar farms and > > export power to the rest of the world! > > > > ----- > > > > A quote relevant to this topic: > > > > "In fact, a solar array 150 x 150 km could, in principle, meet all of > North > > America's energy needs. But PV technology is still more expensive than > grid > > power, lacks a suitable load-balancing solution and requires considerable > > space for electricity generation." > > > > If I've done the conversion factor correctly that's 9000 square miles. > > That's 10% less area than the old 2002 article I found earlier had > proposed. > > > > > >> so if my above figures are correct (which is highly > >> unlikely) we could get by on say 4/80 or 5% of the above > >> area. > >> > >> Double this to 10% for inefficient area utilisation (which I > >> had meant to include) to get 10%. > >> = 1000 square miles or about 30 miles x 30 miles. > >> > >> By all means revisit my assumptions and find my [purposeful > >> [tm]] errors and report back. > >> > >> Doing it would be the hard part :-). > >> > >> 15% is about as good as the best realistic single junction > >> solar arrays. They'll get better and other means will give > >> them a run for their money so I think 15% is not too bad a > >> guesstimate. > >> > >> > >> > >> > >> > >> Russell McMahon > >> > > > > > > > -

"North America" usually refers to Canada and parts of Mexico as well. ...I am wondering if these estimates include grid-cable losses, as well. --Bob Axtell Paul Hutchinson wrote: {Quote hidden}> Last night I was reading this weeks EETimes and found it has an article on > the seventeenth annual Photovoltaic Science and Engineering Conference. > > http://www.eetimes.com/news/design/showArticle.jhtml;?articleID=206902796 > > A quote relevant to this topic: > > "In fact, a solar array 150 x 150 km could, in principle, meet all of North > America's energy needs. But PV technology is still more expensive than grid > power, lacks a suitable load-balancing solution and requires considerable > space for electricity generation." > > If I've done the conversion factor correctly that's 9000 square miles. > That's 10% less area than the old 2002 article I found earlier had proposed. > > Paul Hutch > > >> {Original Message removed}

Rolf wrote: > Hmmm... > without delving too much in to politics either, it would be possible > with $3T to produce a few around the world that were strategically > placed (nevada, sahara, etc.) such that as one region experiences a sun > set the next region is coming online.... with some smart energy > management it may be possible to distribute the energy worldwide as > required and not have to come up with some serious energy buffering > strategies that local geography would require. > > Somehow I don't think the current international 'political climate' will > allow for 'certain' countries to maintain a localized control of the > energy resources for the rest of the world.... unless that country is > the US, of course.... meet the OPEC's future sibling, the OSEEC > (Organisation of Solar Energy Exporting Countries). > > Rolf > > Good idea.

Rolf wrote: {Quote hidden}> Hmmm... > without delving too much in to politics either, it would be possible > with $3T to produce a few around the world that were strategically > placed (nevada, sahara, etc.) such that as one region experiences a sun > set the next region is coming online.... with some smart energy > management it may be possible to distribute the energy worldwide as > required and not have to come up with some serious energy buffering > strategies that local geography would require. > > Somehow I don't think the current international 'political climate' will > allow for 'certain' countries to maintain a localized control of the > energy resources for the rest of the world.... unless that country is > the US, of course.... meet the OPEC's future sibling, the OSEEC > (Organisation of Solar Energy Exporting Countries). > > Rolf > > > Mike Reid wrote: > >> Without delving too much in to the realm of politics, I would like to point >> out that if you took the cost of the Iraq war ($3 trillion when you take in >> to account the future interest payments and care of veterans, infrastructure >> costs, etc.) you could probably build a number of these solar farms and >> export power to the rest of the world! >> >> ----- >> >> A quote relevant to this topic: >> >> "In fact, a solar array 150 x 150 km could, in principle, meet all of North >> America's energy needs. But PV technology is still more expensive than grid >> power, lacks a suitable load-balancing solution and requires considerable >> space for electricity generation." >> >> If I've done the conversion factor correctly that's 9000 square miles. >> That's 10% less area than the old 2002 article I found earlier had proposed. >> >> >> >>> so if my above figures are correct (which is highly >>> unlikely) we could get by on say 4/80 or 5% of the above >>> area. >>> >>> Double this to 10% for inefficient area utilisation (which I >>> had meant to include) to get 10%. >>> = 1000 square miles or about 30 miles x 30 miles. >>> >>> By all means revisit my assumptions and find my [purposeful >>> [tm]] errors and report back. >>> >>> Doing it would be the hard part :-). >>> >>> 15% is about as good as the best realistic single junction >>> solar arrays. They'll get better and other means will give >>> them a run for their money so I think 15% is not too bad a >>> guesstimate. >>> >>> >>> >>> >>> >>> Russell McMahon >>> >>> >> >> > > > The article in Scientific American about 4-5 months ago discussed the grid-loss problem, and suggested using "zero-resistance" cabling, superconducting cable kept at very cold temperatures, and shipping hydrogen gas by pipeline. --Bob

David VanHorn wrote: >> The article in Scientific American about 4-5 months ago discussed the >> grid-loss problem, and >> suggested using "zero-resistance" cabling, superconducting cable kept at >> very cold temperatures, >> > > Yeah, that'll work in the desert, in the summer, tornadoes... > > Power utilities are already using superconductors for runs of a few KM I am led to believe. Not to say it wouldn't be a big job to ring the earth in super conducting wire + infrastructure but it would be good practise for giving mars a magnetosphere. >> and shipping hydrogen gas by pipeline. >> > > I wonder how much would leak away. > That would be the scary part I feel. > Next, the nutcases will be screaming about how we'd use up all the > earth's water! :) >

>> People are currently using small diameter (50mm?) pipe to >> carry Hydrogen around a km or two from a microhydro >> scheme >> to the point of use. Far cheaper than using electric >> transmission apparently. >> > What is there conversion system like at the two ends? > What efficiancy do they get? Gargoyle ... Search Hylink Totara Valley for much more, I imagine The most pleasing thing below is the high pipeline efficiency and capacity. 98% at 1kW range but with they say 240 kW capacity. (Plastic pipe). NZ system. Industrial research demo on a farm. Wind turbine 2 KW Electrolyser 2 km hydrogen pipeline Electrolyser 66% Pipeline 98% up to 240 KW ! Fuel cell 35% up to 1 kW Overall 23% Target 43% Burning the Hydrogen would give about 90% + for about 60% overall. I suspect the electrolyser should be able to be vastly improved over 66%. 20 powerpoint slides Good overview. http://energy.massey.ac.nz/Documents/conference/Conference%20Presentations/Steve%20Broome.ppt

On Fri, Mar 14, 2008 at 9:58 AM, Cedric Chang <@spam@ccKILLspamnope9.com> wrote: > > Someone said they had a link to a proposal to use 10 or 100 square > miles of sunny desert land to make hydrogen and oxygen from water and > solar energy. Can anyone direct me to this proposed solar farm ? A Salon article was recently posted on this subject: http://www.salon.com/news/feature/2008/04/14/solar_electric_thermal/ I'm curious about the heat storage component that they talk about. Developed by H.E. Wilsie. I couldn't find anything via a google search, does anyone know more details? It seems to me that a better way of providing enery during the night would be an agreement with the hydro people to increase their production during the night / reduce it during the day. But I don't know much about how the energy 'market' works, so that might be a non-starter. Alex

Alex Wrote: >It seems to me that a better way of providing enery during the night >would be an agreement with the hydro people to increase their >production during the night / reduce it during the day. But I don't >know much about how the energy 'market' works, so that might be a >non-starter. I was fairly heavily involved in the US energy trading market about 5 years ago, and unless something major has changed hydro is the closest thing they have to a generation 'battery'. So, 'wasting' it during off-peak hours isn't going to fly. Some hydro plants even pump water back into the top reservoir during the night so that they can provide electricity for peak hours the following day. They call this 'pumped storage', and use pump turbines that can both generate or pump depending on demand. This is economically viable due to the large difference between peak and off-peak power costs. Andy.

There was a solar plant for many years in Yermo, CA. I'm in Las Vegas right now at the National Association of Broadcasters convention and have driven by the plant every year or the past 35 years. It used molten salt for heat storage to generate electricity at night. A little about the plant is here: http://virtualglobetrotting.com/map/19342/ . Google Maps shows it here" maps.google.com/maps?ie=UTF8&oe=utf-8&client=firefox-a&q=Yermo,+CA,+USA&ll=34.890894,-116.675306&spn=0.014327,0.033302&t=h&z=15 . Driving by it, you could see a tower with a black "boiler" at the top. When the system was operating, the black boiler glowed a very bright white. A little west of there is Tehachapi which has a lot of wind generators. It's also home to a Borax mine where they used "twenty mule teams" to haul the ore from the mine to the railroad head. Also, about 20 or 30 years ago, in the Carrisa Plain area of California, ARCO Solar had a large photovoltaic power plant. A whole bunch of panels were steered to track the sun. The resulting power was fed back into the grid. Also, the comment about backing down hydro plants during the day and use them for nighttime energy production was interesting. Here in CA, nighttime power from the Diablo Canyon nuclear power plant pumps water up hill at the Helms Project. That water then goes back down hill to increase the peak power capacity of the system. There is some discussion of it at https://eed.llnl.gov/flow/pdf/CA-84.pdf . This also mentions the Yermo solar plant. This also mentions the Carrisa Plain solar plant. A few years back, in California, we were able to pick our power producer. for a few percent more than normal, we could choose to have our power produced from wind, solar, and hydro. Somehow the price to consumers was capped, so when energy prices went up, our bill for production from Green Mountain Energy went way up, but our bill from PG&E for distribution went negative such that our total bill stayed under the cap. This, of course, did not work out well for PG&E. The "choose your producer" plan was scrapped and the governor recalled. I thought the idea of choosing your producer or resource mix was a good idea, but did not think the price caps made sense. There was some gaming the system by producers (and Enron got into trouble for that), but without tricks like that, it seems a competition between producers could work. Ideally producers would compete to be the most green. Harold -- FCC Rules Updated Daily at http://www.hallikainen.com - Advertising opportunities available!

> I was fairly heavily involved in the US energy trading > market about 5 years > ago, and unless something major has changed hydro is the > closest thing they > have to a generation 'battery'. So, 'wasting' it during > off-peak hours isn't > going to fly. Solar thermal plants such as currently the world's largest - the 64 MW Luz built solar trough concentrator installation in Nevada, USA use molten salt thermal storage to get about 7 hours of off-sun storage. Abengoa of Spain are about to build a 280 MW installation at Gila Bend* - near Arizona USA. It also uses thermal storage to allow input smoothing during day to day operations and 'into the night'. Scheduled to commence power generation in 2011. Russell * Advice: NEVER camp in a tent in Gila Bend trailer park in midsummer !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! :-)

> Solar thermal plants such as currently the world's > largest - > the 64 MW Luz built solar trough concentrator installation > in Nevada, USA use molten salt thermal storage to get > about > 7 hours of off-sun storage. > > Abengoa of Spain are about to build a 280 MW installation > at > Gila Bend* - near Arizona USA. It also uses thermal > storage > to allow input smoothing during day to day operations and > 'into the night'. Scheduled to commence power generation > in > 2011. Serendipitously, this just turned up as a reference in an email newsletter "Barriers to Commercialisation of Large-Scale Solar Electricity:- Lessons learned from the Luz experience" http://www.nrel.gov/csp/troughnet/pdfs/sand91_7014.pdf While this is a 1991 Sandia report it was actually written by the previous President for business development for Luz, so his perspective is partisan, but useful. The Nevada Luz solar thermal parabolic concentrator plant was and AFAIK still is the worlds largest. It was built on the subsidy structure of the 1970's oil shocks and the com,pany foundered when the nightmare memories faded and the pricing structures were varied. The plant itself remained viable as a cash cow and is still chugging along nicely some 20+ years on. The new Gila Bend plant will be bigger. The latest "carbon credits" regime helps the economic viability of such plants. They are not too uncompetitive compared with alternatives and if eg 'cheap' hydrocarbons were not available the cost jump to cost effective operation would not be vast. As noted, longer term night storage than the existing thermal is desirable. Pumped hydro is one option. NZ has substantial hydro % capacity and is currently looking at a 5% chance of winter power shortages due to low summer lake inflows. Russell