Solar Panels, Moors' Law, closed food systems

[Nosi]

Moor's Law has done wild things to the world of micro computing and personal computers. I think there are signs of it (http://images.google.com/imgres?imgurl=http://imagesme.net/igreenspot/teatro-del-agua-solar-desalination-plant1.jpg&imgrefurl=http://www.igreenspot.com/teatro-del-agua-by-grimshaw-architects/&usg=__1XBD4SWq_IpZxSnFcjeBF6FN3K8=&h=324&w=450&sz=46&hl=en&start=1&um=1&tbnid=BJItyjPughWZoM:&tbnh=91&tbnw=127&prev=/images%3Fq%3Dsolar%2Bpanels%2Bdesalination%26hl%3D en%26safe%3Doff%26client%3Dfirefox-a%26rls%3Dcom.ubuntu:en-US:unofficial%26sa%3DN%26um%3D1) coming into play in alternative energy, particularly solar energy and solar panels.

Today, desalination of sea water is an expensive proposition only for rich coastal cities such as Saudi Arabia using massive amounts of oil based fuel. As water gets scarcer, solar energy, desalination, and hydroponics will begin to make the production of our food and food chain a closed system (http://nymag.com/news/features/30020/) with much less waste.

We already have hothouse crops for premium fruits and vegetables for the fussy eaters willing to pay premium prices. Skyfarms (http://nymag.com/news/features/30020/) will probably cater to the premium set at first in order to get the concern going.

While are expensive to set up, but they lack some very major expenses of open-air farming. There's low to nonexistent risk of e-coli contamination from animal excreta, and predators of fruits and veggies won't bother them, with the possible thief exception. You can grow 27/7-365.

[GreenLines]

Moore's Law was an observation on the number of transistors on a chip double every two years, with the cost decreasing per transistor by 30% over the same amount of time.

Solar panel cost per megawatt has NOT decreased in the past decade, and has been stable for the past twenty years[1].

"As water gets scarcer"? I don't see water getting any scarcer, it's probably one of the most abundant compounds on the planet. I'm going to assume you meant usable water.

A farm going into the sky powered by a huge solar panel with additional power from waste products? Good luck getting a self contained system like that going in the next hundred years. Biomass probably wouldn't give a tenth of the power, and the solar panel during nighttime might give enough for a quarter of the energy needs of lighting. But I guess I should have read that again, since it's meant to supply cooling rather then lighting. As long as there's direct sunlight I can see that working out.

Hydroponics are a good idea, that I can go with. The system all seems kind of pie in the sky and not as sustainable as the article makes it seems. Would need a LOT of, in my opinion, outside energy.

[1]Photovoltaic System, Second Edition. Figure 1-7, page 8.

[Dancing David]

You can also desalinate water with plastic sheeting and two or three troughs.

[macdoc]

Solar panel cost per megawatt has NOT decreased in the past decade, and has been stable for the past twenty years[1].

I take it you are unfamiliar with NanoSolar

http://www.celsias.com/article/nanosolars-breakthrough-technology-solar-now-cheap/

http://www.technologyreview.com/business/23482/

http://www.greentechmedia.com/articles/read/nanosolar-boosts-cells-efficiency-starts-mass-production/

[Cuddles]

I take it you are unfamiliar with NanoSolar

Nanosolar is certainly a step in the right direction, but a single breakthrough by one company can hardly be taken as evidence of a Moore's law equivalent for solar power.

hydroponics will begin to make the production of our food and food chain a closed system (http://nymag.com/news/features/30020/)

No it won't. Food production can never be a closed system, by definition. If it were closed, you wouldn't get food out. Since you do get food out, there must also be inputs, unless you plan on generating matter from nowhere. Reducing waste is certainly an admirable goal, but food production can never be a closed system. At least not without defining the system in such a way as to make the claim a pointless tautology.

[macdoc]

Umm the statement was made there was "no change in 20 years" of solar costs.
That statement is incorrect. I did not address the patently silly Moore's law nonsense.

There are dozens of other examples of reduced costs/improved yield in even traditional solar panels.

••••

With carbon neutral energy sources food can be a closed sustainable series of loops....good agriculture already does that by effectively reprocessing waste.

Since agriculture is mainly solar anyway there is no barrier there - it's yield and transport that is the issue.
Mining agricultural land by way of unsustainable practices ( Australia notably ) is a sure way to societal suicide.

[Nosi]

Food production can never be a closed system, by definition. If it were closed, you wouldn't get food out. Since you do get food out, there must also be inputs, unless you plan on generating matter from nowhere. Reducing waste is certainly an admirable goal, but food production can never be a closed system. At least not without defining the system in such a way as to make the claim a pointless tautology.

Oh... seeds in, plants out. I can see where that would be a problem with 'closed system'.

[IchabodPlain]

Moor's Law has done wild things to the world of micro computing and personal computers. I think there are signs of it (http://images.google.com/imgres?imgurl=http://imagesme.net/igreenspot/teatro-del-agua-solar-desalination-plant1.jpg&imgrefurl=http://www.igreenspot.com/teatro-del-agua-by-grimshaw-architects/&usg=__1XBD4SWq_IpZxSnFcjeBF6FN3K8=&h=324&w=450&sz=46&hl=en&start=1&um=1&tbnid=BJItyjPughWZoM:&tbnh=91&tbnw=127&prev=/images%3Fq%3Dsolar%2Bpanels%2Bdesalination%26hl%3D en%26safe%3Doff%26client%3Dfirefox-a%26rls%3Dcom.ubuntu:en-US:unofficial%26sa%3DN%26um%3D1) coming into play in alternative energy, particularly solar energy and solar panels.

Today, desalination of sea water is an expensive proposition only for rich coastal cities such as Saudi Arabia using massive amounts of oil based fuel. As water gets scarcer, solar energy, desalination, and hydroponics will begin to make the production of our food and food chain a closed system (http://nymag.com/news/features/30020/) with much less waste.

We already have hothouse crops for premium fruits and vegetables for the fussy eaters willing to pay premium prices. Skyfarms (http://nymag.com/news/features/30020/) will probably cater to the premium set at first in order to get the concern going.

While are expensive to set up, but they lack some very major expenses of open-air farming. There's low to nonexistent risk of e-coli contamination from animal excreta, and predators of fruits and veggies won't bother them, with the possible thief exception. You can grow 27/7-365.

I do not see why having a closed system is more beneficial than an open system (though I'm sure the optimal mix is somewhere in between). For instance, introducing more organisms which contribute to plant health and growth is a good thing. There is no waste in nature. By having organisms such as earthworms in the process of food production, or certain insects which repel or are predators of other organisms which stifle or otherwise reduce yield, you can increase capacity and sustainability.

[GreenLines]

Umm the statement was made there was "no change in 20 years" of solar costs.

Your links did not directly address the cost to the consumer, which I think the graph I'm looking at does. There is a note pointing out that "Retail price per watt of crystalline silicon modules" so in that respect the "NanoSolar" would likely not have been included.

Additionally, there isn't any mention of price to the consumer that I saw (though I have a habit of overlooking things, so if I miss something, don't be surprised), but there was mention that the plant is producing less then a twentieth of a percent of its capacity. That's bound to make prices to the final customer go up a bit.

http://www.celsias.com/article/nanosolars-breakthrough-technology-solar-now-cheap/

http://www.technologyreview.com/business/23482/

http://www.greentechmedia.com/articles/read/nanosolar-boosts-cells-efficiency-starts-mass-production/

First article: Only thing that really pops out as being wrong is that solar panels have been around for over fifty years, not thirty. They were first used in rural telecommunication lines.

Second article: I don't see these panels as making installation less complicated. There's still going to be the need for power conditioning, and higher output means higher gauge wire, meaning initial cost outside of the solar panels could be slightly higher. I do applaud getting around that annoying shade issue. A 20% shade coverage can cripple 50% of the power coming out of a traditional array.

Third article: Makes mention of Photon magazine, sounds like a trade paper to me, might have to subscribe to that.

I have a vested interested in solar panels being more cost effective, easier to install/maintain, and producing more electricity. Hopefully by the end of May I'll have a certification in installing these suckers.

[GanipGnop]

Solar panel cost per megawatt has NOT decreased in the past decade, and has been stable for the past twenty years[1].



Yes it has Nanosolar isn't the only company offering cheap new solar technology. Everbrightsolar uses thin film ribbon technology to decrease their silicon waste. Old styled silicon cells are cut out of blanks wasting as much as 50% of the blank. Thin film silicon ribbons are made by melting the silicon and drawing a carbon filament through it to create an ultra thin ribbon of silicon the waste ratio is 1-5%. They can use recycled ultra pure silicon from bad microprocessor production runs and other ultra pure "waste" to bring costs down.

Find me some UL listed 175 watt grid tie panels for $436 each 20 years ago (remember to adjust for inflation). I own a few of these panel now and they work great I intend to buy a few more along with a MPPT charge controller with my tax refund this year. I'm not off the grid but I have a large enough battery bank to run some lights and a small TV or radio for 5 or 6 evenings.

http://www.everbrightsolar.net/ul-approved-solar-panels.html

http://www.discountpv.com/charge_controllers/mppt250hv.htm

I agree that Moore's law doesn't apply here this price drop is coming from new production methods an increased efficiency, the economy of scale and the 30% US federal tax break but that $436 price doesn't include the tax credit, solar power is cheaper today than 20 years ago and it will get cheaper.




http://www.everbrightsolar.net/info.html

[GreenLines]

Yes it has...

To be fair to me, I'm using a slight piece of knowledge gained from a traditional school textbook. Bound to be some discrepancies to reality.

[GanipGnop]

To be fair to me, I'm using a slight piece of knowledge gained from a traditional school textbook. Bound to be some discrepancies to reality.

To be truly fair I'm not saying every company is selling solar power panels this cheap but the price is coming down.

[GreyICE]

Moore's Law was an observation on the number of transistors on a chip double every two years, with the cost decreasing per transistor by 30% over the same amount of time.

Solar panel cost per megawatt has NOT decreased in the past decade, and has been stable for the past twenty years[1].
O RLY:
http://www1.eere.energy.gov/tribalenergy/guide/images/chart3_solar_pv.gif http://www1.eere.energy.gov/tribalenergy/guide/costs_solar_photovoltaics.html

US DOE

ETA: The 'cost to the consumer (aka price)' is driven by market demand. The supply is driven by cost. Interesting that, Econ 101 strikes again.

[GreenLines]

O RLY: http://www1.eere.energy.gov/tribalenergy/guide/costs_solar_photovoltaics.html

US DOE

ETA: The 'cost to the consumer (aka price)' is driven by market demand. The supply is driven by cost. Interesting that, Econ 101 strikes again.

And as I clarified in a later post, and I'm agreeing that I was wrong, is that the graph I was looking at was based on "Retail price per watt of crystalline silicon modules", leaving out other types of "photovoltaic" panels.

[portlandatheist]

I'm sad to say that photovoltaics have made only incremental improvements and not exponential improvements and its likely to stay that way. The next biggest innovations to look forward to is not any improvements in efficiency, but rather the cost of production and the final cost to the consumer.
Can you imagine a day when the manufacturers of solar panels choose to use solar power themselves to make their own product? Now that would be impressive but I would bet dollars to donuts that I won't live to ever see such a day. Solar power is great for remote locations such as space, but not as a base energy source.

[GanipGnop]

I'm sad to say that photovoltaics have made only incremental improvements and not exponential improvements and its likely to stay that way. The next biggest innovations to look forward to is not any improvements in efficiency, but rather the cost of production and the final cost to the consumer.
Can you imagine a day when the manufacturers of solar panels choose to use solar power themselves to make their own product? Now that would be impressive but I would bet dollars to donuts that I won't live to ever see such a day. Solar power is great for remote locations such as space, but not as a base energy source.

Hey look a 12 year old boy thinks you're wrong

"In his project, 'A Highly-Efficient 3-Dimensional Nanotube Solar Cell for Visible and UV Light,' William invented a novel solar panel that enables light absorption from visible to ultraviolet light. He designed carbon nanotubes to overcome the barriers of electron movement, doubling the light-electricity conversion efficiency. William also developed a model for solar towers and a computer program to simulate and optimize the tower parameters. His optimized design provides 500 times more light absorption than commercially-available solar cells and nine times more than the cutting-edge, three dimensional solar cell."

http://www.katu.com/news/28432984.html

http://presskit.ditd.org/2008_Davidson_Fellows_Press_Kit/2008_DF_William_Yuan.pdf

[GreenLines]

http://www.katu.com/news/28432984.html

"If he is right", and believe me, I hope he is. If it's a feasible design, get it going as soon as possible. Cash in and be a millionaire.

[Brian-M]

You can also desalinate water with plastic sheeting and two or three troughs.


Through the evaporated water condensing in droplets on the plastic, and running down into a different container I assume?

Just a wild guess, but you'd probably need more than a quarter-acre of land filled with these troughs just to supply enough drinking water for one person. To supply enough fresh water to irrigate your crops as well... that comes to a hell of lot of land.

[Dilb]

Hey look a 12 year old boy thinks you're wrong

"In his project, 'A Highly-Efficient 3-Dimensional Nanotube Solar Cell for Visible and UV Light,' William invented a novel solar panel that enables light absorption from visible to ultraviolet light. He designed carbon nanotubes to overcome the barriers of electron movement, doubling the light-electricity conversion efficiency. William also developed a model for solar towers and a computer program to simulate and optimize the tower parameters. His optimized design provides 500 times more light absorption than commercially-available solar cells and nine times more than the cutting-edge, three dimensional solar cell."

http://www.katu.com/news/28432984.html

http://presskit.ditd.org/2008_Davidson_Fellows_Press_Kit/2008_DF_William_Yuan.pdf

It's extremely unclear what exactly he did, but no, this isn't going to improve the efficiency of solar cells anything like how Moore's law applies to transistors. Solar cells are typically ~8% efficient outside the lab, so it's literally impossible to improve them more than about 1 order of magnitude. There already are ~50% efficient solar cells, which need conditions like 100 suns intensity of light on a fresh cell, and wear out in a few months. In comparison, there are still several orders of magnitude before hitting any thermodynamic limits of computing, and there were dozens when Moore's law was first observed.

I'm not sure what they mean by 500 times more absorption, but a solar cell that produces 500 times as much power is definitely not what's going to happen.

[Cuddles]

Solar cells are typically ~8% efficient outside the lab, so it's literally impossible to improve them more than about 1 order of magnitude.

This is the point I was going to make. Moore's law is possible because we have not reached the limit of how small transistors can be. When the law was first stated we were many orders of magnitude away from that, so massive gains were possible. The expanded law, referring to processing power rather than just transistors, has potential to keep going even after we reach the limit on transistors, because we are nowhere near the theoretical limit of information processing.

Solar power, on the other hand, has a very hard limit - the amount of power actually coming from the Sun. I was going to speculate that the increase of hundreds of times was a result of only measuring the efficiency across a certain range of wavelengths, so being able to absorb more could result in a much larger increase. However, it appears that the standard measure calculates efficiency as the ratio of output power to total irradiance from the Sun, so it is impossible to ever get higher than 100%, and therefore any claim involving an increase of more than about 3 times must be wrong (highest achieved efficiency is a little over 40% in the lab, around 25% commercially available).

This boy may well have come up with a neat idea, but he's not going to magically make solar cells produce more energy that is actually coming from the Sun in the first place.

[technoextreme]

However, it appears that the standard measure calculates efficiency as the ratio of output power to total irradiance from the Sun, so it is impossible to ever get higher than 100%, and therefore any claim involving an increase of more than about 3 times must be wrong (highest achieved efficiency is a little over 40% in the lab, around 25% commercially available).

There is no standard.
"In his project, 'A Highly-Efficient 3-Dimensional Nanotube Solar Cell for Visible and UV Light,' William invented a novel solar panel that enables light absorption from visible to ultraviolet light. He designed carbon nanotubes to overcome the barriers of electron movement, doubling the light-electricity conversion efficiency. William also developed a model for solar towers and a computer program to simulate and optimize the tower parameters. His optimized design provides 500 times more light absorption than commercially-available solar cells and nine times more than the cutting-edge, three dimensional solar cell."
You can't make carbon nanotubes consistently. Its an impossible pipe dream at the moment. It also sounds like plagerized other people's work.
Moore's law is possible because we have not reached the limit of how small transistors can be.
Yes actually we have.

[Cuddles]

There is no standard.

Yes there is (http://www.astm.org/cgi-bin/SoftCart.exe/STORE/filtrexx40.cgi?U+mystore+eteh4957+-L+G173NOT:(STATUS:%3CNEAR/1%3E:REPLACED)+/usr6/htdocs/astm.org/DATABASE.CART/REDLINE_PAGES/G173.htm).

[technoextreme]

Yes there is (http://www.astm.org/cgi-bin/SoftCart.exe/STORE/filtrexx40.cgi?U+mystore+eteh4957+-L+G173NOT:(STATUS:%3CNEAR/1%3E:REPLACED)+/usr6/htdocs/astm.org/DATABASE.CART/REDLINE_PAGES/G173.htm).
Its an industry standard which means squat didly to a scientist in a laboratory. In the lolipops and candycane world that you live in it would be nice to actually be able to quickly compare papers off of a nice standard. The reality is that its a painful experience because everyone's definition is different.

[Dilb]

Its an industry standard which means squat didly to a scientist in a laboratory. In the lolipops and candycane world that you live in it would be nice to actually be able to quickly compare papers off of a nice standard. The reality is that its a painful experience because everyone's definition is different.

The science of how solar cells work stopped being an interesting question quite a while ago. The scientists working on solar cells nowadays (and they have labs and everything) are quite aware that they want to build a practical product which will be exposed to sunlight. You can buy artificial sunlight sources (http://www.radiantsourcetechnology.com/html/solar_applications.html) straight from the catalogue.

[Cuddles]

Its an industry standard which means squat didly to a scientist in a laboratory. In the lolipops and candycane world that you live in it would be nice to actually be able to quickly compare papers off of a nice standard. The reality is that its a painful experience because everyone's definition is different.

What on Earth are you babbling about? There certainly is a standard way to measure the efficiency of solar cells - you measure the ratio between the total incoming power and the output. I had speculated that perhaps some people only considered the incoming energy within a certain range of wavelengths, which could explain how anyone could think a 500* increase in efficiency might be possible. However, it appears that that is not the case. If you would like to present evidence that some people do measure efficiency in a completely different way, feel free to present it. Your condescending attitude would be bad enough if you actually had a point, but given that you appear to completely wrong as well it's really rather sad.

[portlandatheist]

Hey look a 12 year old boy thinks you're wrong

"In his project, 'A Highly-Efficient 3-Dimensional Nanotube Solar Cell for Visible and UV Light,' William invented a novel solar panel that enables light absorption from visible to ultraviolet light. He designed carbon nanotubes to overcome the barriers of electron movement, doubling the light-electricity conversion efficiency. William also developed a model for solar towers and a computer program to simulate and optimize the tower parameters. His optimized design provides 500 times more light absorption than commercially-available solar cells and nine times more than the cutting-edge, three dimensional solar cell."

http://www.katu.com/news/28432984.html

http://presskit.ditd.org/2008_Davidson_Fellows_Press_Kit/2008_DF_William_Yuan.pdf
Yes indeed, a 12 year old thinks I'm wrong. Perhaps because he hasn't been disappointed with the promise of solar energy being "right around the corner" for the past 30 years as I have even though there has been no end to media hype about it during that time frame.
We know solar photovoltaics don't follow Moore's law based on its existing history. How much further along are we with photovoltaics than we were in 1970? Or the last 100 years for that matter? Certainly, there will be impressive innovations and discoveries, but don't hold your breath for the day we can power our society with them. One of the more important metrics, along with efficiency, is the cost of kWh over the lifetime of the cells. In a climate like mine, that would be something like 77.48 cents kWh source (http://www.solarbuzz.com/solarindices.htm)
Solar concentrators and wind power are more promising technologies. I look forward to new technologies with solar power but I'm not anticipating any miracles along the lines of Moore's law. It just isn't very likely to happen.

[GreenLines]

How much further along are we with photovoltaics than we were in 1970? Or the last 100 years for that matter?

From what I understand, which has been shown to not be much or very accurate, photovoltaics started with selenium, moved to silicon, and now has that CIGS stuff. So I would guess that it moves in leaps every fifty years or so. Have fun waiting for the next well spread and well implemented system.

[Nosi]

I wonder, maybe pure solar cells like you saw on roofs in the 80's are a mature tech, but combined with other things...they may complement (I'm talking out of my :rule10 very late at night so take me with a grain of salt). Some kind of battery, windmill, solar cell nuke combination... Each tech adding to the efficiency of the others.

[soylent]

If anything they seem to be making logarithmic improvements as time goes on, but I guess that could be a kind of a twisted inverse to Moore's law.

[ThunderChunky]

Solar power, on the other hand, has a very hard limit - the amount of power actually coming from the Sun. I was going to speculate that the increase of hundreds of times was a result of only measuring the efficiency across a certain range of wavelengths, so being able to absorb more could result in a much larger increase. However, it appears that the standard measure calculates efficiency as the ratio of output power to total irradiance from the Sun, so it is impossible to ever get higher than 100%, and therefore any claim involving an increase of more than about 3 times must be wrong (highest achieved efficiency is a little over 40% in the lab, around 25% commercially available).


I agree with your point, but what really matters is the cost per watt. That can continue to go down after the theoretical limits of efficiency are approached.

[jimbob]

Rather than starting a new thread:




Report Claims Solar Energy Now Cheaper Than Nuclear Power (in North Carolina)
(http://www.powerpulse.net/story.php?storyID=22670)
Duke University has issued a report claiming that solar energy costs are now cheaper than those of nuclear energy after what it describes as a "historic crossover" in North Carolina.

The study was written by John O. Blackburn, professor of economics at Duke University in North Carolina, and Sam Cunningham, a graduate student at Duke. Titled "Solar and Nuclear Costs – The Historic Crossover," the study states that changes in cost on both solar and nuclear energy have brought the competing energy sources to a point of equality, and that now solar has become the lower-cost renewable energy resource.

The authors argue that solar energy costs have met nuclear energy costs, which occurred at 16 cents per kilowatt hour, then fell below nuclear costs, and that there is hope that the push for nuclear will slow down and that the government may look to a combination of solar and other renewable energy resources that are low carbon and low cost.

The other points in the report are interesting (I am just not quoting them for copyright reasons).

I think that solar is starting out as a niche application, and as it grows, and matures, it will increase the area that it can serve. I guess that North Carolina is more sunny than much of the US, but even so, this suggests that solar is now more viable than nuclear there.

There is a lot of activity aimed at improving the real-world efficiency of solar panels, for example, Solar magic by National Semiconductor (http://www.solarmagic.com/power_optimization)

Power optimization increases PV system energy harvest and maximizes ROI by correcting hidden imbalance and extending system life. Imbalance is caused by current or voltage mismatch and can prevent systems from meeting performance expectations. SolarMagic™ power optimization improves system output regardless of environmental conditions, weather, or design. Independent studies have shown that SolarMagic power optimization recaptures up to 71% of energy lost to mismatch.



SolarMagic power optimization technology was installed at Oak Street Affordable Housing unit in Oakland, California. According to Jigar Shah, founder of SunEdison, "For over four years, our Oak Street installation has been helping residents pay less electricity. SolarMagic is helping us to get 22.6 percent more power out of the same panels, making the system even more productive and cost effective."

As well as this, there is the actual cost of producing the solar panels, which has plenty of scope to fall.

With concentrating solar, one can of course get more efficiency per unit area of solar cell, for an additional cost of some mirrors and control electronics.

There is a penalty, because these might run hot, so need additional cooling, but this paper (http://www.nature.com/nmat/journal/v9/n9/full/nmat2814.html) in nature is interesting in that respect:

Photon-enhanced thermionic emission for solar concentrator systems

Jared W. Schwede1,2,3, Igor Bargatin4, Daniel C. Riley1,2,3, Brian E. Hardin1,5, Samuel J. Rosenthal1,5, Yun Sun6, Felix Schmitt1,2, Piero Pianetta6, Roger T. Howe4, Zhi-Xun Shen1,2,3 & Nicholas A. Melosh1,2,5

Abstract

Solar-energy conversion usually takes one of two forms: the ‘quantum’ approach, which uses the large per-photon energy of solar radiation to excite electrons, as in photovoltaic cells, or the ‘thermal’ approach, which uses concentrated sunlight as a thermal-energy source to indirectly produce electricity using a heat engine. Here we present a new concept for solar electricity generation, photon-enhanced thermionic emission, which combines quantum and thermal mechanisms into a single physical process. The device is based on thermionic emission of photoexcited electrons from a semiconductor cathode at high temperature. Temperature-dependent photoemission-yield measurements from GaN show strong evidence for photon-enhanced thermionic emission, and calculated efficiencies for idealized devices can exceed the theoretical limits of single-junction photovoltaic cells. The proposed solar converter would operate at temperatures exceeding 200 °C, enabling its waste heat to be used to power a secondary thermal engine, boosting theoretical combined conversion efficiencies above 50%.

[jimbob]

And of course the photovoltaic approach is not the only one.

[Cuddles]

this suggests that solar is now more viable than nuclear there.

If you look at cost alone, maybe. If you include all the other rather important factors, such as clouds and night, it's clear that solar power will never be the solution on its own. Until we find a renewable power source that is capable of providing continuous, reliable base load, we're going to need either nuclear or to keep burning stuff. As far as I know only geothermal and wave power currently have any hope of achieving that, and neither is going to work in many places.

[Ririon]

If you look at cost alone, maybe. If you include all the other rather important factors, such as clouds and night, it's clear that solar power will never be the solution on its own. Until we find a renewable power source that is capable of providing continuous, reliable base load, we're going to need either nuclear or to keep burning stuff. As far as I know only geothermal and wave power currently have any hope of achieving that, and neither is going to work in many places.
There was no single solution at any point in history for all our energy needs (at least not after our ancestors started using fire). So obviously there will never be a single solution to save us from everything. Solar panels is one solution with huge potential in many places. It will get cheaper, but Moore's law is a rather extreme case. The obvious flaw that it doesn't work at night doesn't mean it is useless. For one thing, it works best when you need the most air conditioning. :) Combined with many other solutions on the grid, it works just fine.

[Cuddles]

There was no single solution at any point in history for all our energy needs (at least not after our ancestors started using fire). So obviously there will never be a single solution to save us from everything. Solar panels is one solution with huge potential in many places. It will get cheaper, but Moore's law is a rather extreme case. The obvious flaw that it doesn't work at night doesn't mean it is useless. For one thing, it works best when you need the most air conditioning. :) Combined with many other solutions on the grid, it works just fine.

I guess it's a good thing I never said there ever was a single solution or that it was in any way useless.:rolleyes:

[Ririon]

I guess it's a good thing I never said there ever was a single solution or that it was in any way useless.:rolleyes:
Good thing. :)

If I may add: Where it is available (like around here) hydroelectric power is excellent for balancing out energy sources that are not reliable 24/7.

[jimbob]

There is molten salt solar thermal generation: (http://en.wikipedia.org/wiki/Solar_thermal_energy#Molten_salt_storage)

[dasmiller]

There was no single solution at any point in history for all our energy needs (at least not after our ancestors started using fire). So obviously there will never be a single solution to save us from everything. Solar panels is one solution with huge potential in many places. It will get cheaper, but Moore's law is a rather extreme case. The obvious flaw that it doesn't work at night doesn't mean it is useless. For one thing, it works best when you need the most air conditioning. :) Combined with many other solutions on the grid, it works just fine.


bah! Are you sure that you understand politics? Any energy solution that meets only part of our energy needs, has any negative impact on the environment, involves any foreign government, requires any infrastructure changes, has significant up-front costs, shifts jobs from one region or market sector to another, or requires more than 6 months to implement, is simply unacceptable.

Why, there are people recommending more use of solar power without even having proved that there's no potential for some regional, economical, or other demographic group to receive more benefit than some other group!

The obvious solution is to do further studies. Perhaps a tiered committee structure, with one (or more!) top-level committees designating study areas to a large number of subcommittees to study various types of potential impacts of hypothetical power-generation systems. I'd estimate a year or two to come up with a good framework for the studies, with preliminary guidelines and a draft list of topics. Then there will be the comments & revision period, followed by a second draft, 2nd round of comments, and then a final set of recommended topics and guidelines which could then be sent out for approval. Of course, there will be a few more iterations before the final approval, but I'd estimate that we could actually start identifying the subcommittees within 5 years if we started today.

I'm assuming that for an accelerated program like this, we could work the funding issues in parallel. No need to stretch out the process!

The candidate selection process for the top-level committees will probably take a year or so, but once that was completed, we could start identifying the host cities and facilities for the subcommittees. There will be a lot of regional interests to balance, but with the usual draft-comments-revision cycle, this shouldn't take more than 2 years.

So, with a lot of political will and some luck, by 2018 we could be ready to actually start work on doing some studies that could potentially identify some of the real concerns associated with changing our national energy strategy.

ETA - gah, I dashed off a quick response without really thinking about it. But before they can start the initial outline, there's going to be at least 6 months to come up with the proper logos and catchphrase. So make it 2019 instead of 2018.


(everybody here has a sense of humor, right?)