Safe Storage of Nuclear Waste

In summary, there is no easy or cheap way to dispose of or store nuclear waste, and it poses a risk to our planet. It would be prohibitively expensive to launch nuclear waste into space, and the most radioactive components decay quickly. The alternatives to storing nuclear waste on Earth are expensive and impractical.
  • #36
baywax said:
This may not be completely related to the thread but, why isn't there more research into the Hydrogen Fuel Cell generators (like the ones being used for individual households in Japan)? This would certainly reduce the waste of resources and the waste disposal issue.
They were using the Fuel Cell on the Apollo missions (40+ years ago), there must have been some advancements with them by now.

As far as I understand, hydrogen fuel cells use a catalytic process to combine hydrogen and oxygen into water, producing electricity. But the fuel for these cells is hydrogen, which can, for instance, be obtained by electrolysis of water.
So it is a kind of battery.
 
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  • #37
vanesch said:
As far as I understand, hydrogen fuel cells use a catalytic process to combine hydrogen and oxygen into water, producing electricity. But the fuel for these cells is hydrogen, which can, for instance, be obtained by electrolysis of water.
So it is a kind of battery.

These things have been around since the 1800s. For some rea$on, they've been kept way on the back burner.

There are several different types of fuel cells, each using a different chemistry. Fuel cells are usually classified by their operating temperature and the type of electrolyte they use. Some types of fuel cells work well for use in stationary power generation plants. Others may be useful for small portable applications or for powering cars. The main types of fuel cells include:

Polymer exchange membrane fuel cell (PEMFC)
The Department of Energy (DOE) is focusing on the PEMFC as the most likely candidate for transportation applications. The PEMFC has a high power density and a relatively low operating temperature (ranging from 60 to 80 degrees Celsius, or 140 to 176 degrees Fahrenheit). The low operating temperature means that it doesn't take very long for the fuel cell to warm up and begin generating electricity. We’ll take a closer look at the PEMFC in the next section.

Solid oxide fuel cell (SOFC)
These fuel cells are best suited for large-scale stationary power generators that could provide electricity for factories or towns. This type of fuel cell operates at very high temperatures (between 700 and 1,000 degrees Celsius). This high temperature makes reliability a problem, because parts of the fuel cell can break down after cycling on and off repeatedly. However, solid oxide fuel cells are very stable when in continuous use. In fact, the SOFC has demonstrated the longest operating life of any fuel cell under certain operating conditions. The high temperature also has an advantage: the steam produced by the fuel cell can be channeled into turbines to generate more electricity. This process is called co-generation of heat and power (CHP) and it improves the overall efficiency of the system.

Alkaline fuel cell (AFC)
This is one of the oldest designs for fuel cells; the United States space program has used them since the 1960s. The AFC is very susceptible to contamination, so it requires pure hydrogen and oxygen. It is also very expensive, so this type of fuel cell is unlikely to be commercialized.

Molten-carbonate fuel cell (MCFC)
Like the SOFC, these fuel cells are also best suited for large stationary power generators. They operate at 600 degrees Celsius, so they can generate steam that can be used to generate more power. They have a lower operating temperature than solid oxide fuel cells, which means they don't need such exotic materials. This makes the design a little less expensive.

Phosphoric-acid fuel cell (PAFC)
The phosphoric-acid fuel cell has potential for use in small stationary power-generation systems. It operates at a higher temperature than polymer exchange membrane fuel cells, so it has a longer warm-up time. This makes it unsuitable for use in cars.

Direct-methanol fuel cell (DMFC)
Methanol fuel cells are comparable to a PEMFC in regards to operating temperature, but are not as efficient. Also, the DMFC requires a relatively large amount of platinum to act as a catalyst, which makes these fuel cells expensive.

http://auto.howstuffworks.com/fuel-cell1.htm
 
  • #38
baywax said:
These things have been around since the 1800s. For some rea$on, they've been kept way on the back burner.

Yes, but don't go thinking that they are a *source* of power. They are, as I said, a kind of battery: they can give back (part of the) electricity that you consumed to make the hydrogen.
 
  • #39
vanesch said:
Sure, the idea is to switch to fast breeders, no ? The current cycle is not only producing annoying waste, it is especially wasteful with ressources!

Hopefully, but if the current prospecting cycle finds a lot of cheap uranium, like it probably will, I think that will put a big dent in the nuclear industries motivation to go towards fast breeders.
 
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  • #40
vanesch said:
Yes, but don't go thinking that they are a *source* of power. They are, as I said, a kind of battery: they can give back (part of the) electricity that you consumed to make the hydrogen.

I'm only mentioning the FC technology as one way to reduce or eliminate nuclear waste. Thank you vanesch.
 
  • #41
baywax said:
I'm only mentioning the FC technology as one way to reduce or eliminate nuclear waste. Thank you vanesch.

In what way would they reduce nuclear waste ??
 
  • #42
vanesch said:
In what way would they reduce nuclear waste ??

I think he means they would reduce nuclear waste if we used some non-nuclear method of generating power to produce hydrogen, then stored and transported power in fuel cells maybe?

But baywax, the thing is, every way we currently have to produce the hydrogen for fuel cells consumes more energy from conventional sources (like nuclear reactors that produce electricity) than ever comes out of the fuel cell. So fuel cells at the moment aren't a solution to the same problem that nuclear power is; nuclear power is for generating energy and fuel cells are for storing energy, as vanesch said they're like batteries. Using fuel cells wouldn't have any effect on whether nuclear waste is produced in generating energy.

Theoretically, if we could find or bioengineer something like bacteria or algae that produce large quantities of hydrogen as a byproduct, and they didn't take too much conventional energy to cultivate, we could maybe get fuel cells and other parts of a hydrogen economy working. But I don't think there's any technology like that even on the horizon.
 
  • #43
CaptainQuasar said:
I think he means they would reduce nuclear waste if we used some non-nuclear method of generating power to produce hydrogen, then stored and transported power in fuel cells maybe?

But baywax, the thing is, every way we currently have to produce the hydrogen for fuel cells consumes more energy from conventional sources (like nuclear reactors that produce electricity) than ever comes out of the fuel cell. So fuel cells at the moment aren't a solution to the same problem that nuclear power is; nuclear power is for generating energy and fuel cells are for storing energy, as vanesch said they're like batteries. Using fuel cells wouldn't have any effect on whether nuclear waste is produced in generating energy.

Theoretically, if we could find or bioengineer something like bacteria or algae that produce large quantities of hydrogen as a byproduct, and they didn't take too much conventional energy to cultivate, we could maybe get fuel cells and other parts of a hydrogen economy working. But I don't think there's any technology like that even on the horizon.

That's right Capt. Q, less emphasis on Nuclear Power as a source of energy would reduce nuclear waste.

As for hydrogen production, solar power is a "free" source of energy, wind and hydro are as well. What's more is the fact that we tend to make leaps in technological discoveries and this is one area where we can use a few. Remember that most computers used to need a warehouse to contain them and that your mobile phone used to be the size of an AK7. I have the feeling that there is an efficient and cheap method of hydrogen extraction just waiting to make someone a lot of money.

Sorry to get off the topic, inadvertently. I am particularly interested in the safe mining and storage of nuclear material since I was one of many who helped to instill a 28 year long moratorium on uranium mining in my province.
 
  • #44
Uranium is already mined safetly and to high environmental standards in Australia and Canada. Its really no worse than other kinds of mining.

There is one simple thing that limits solar power that no technology can change. Its incredibly diluted. About 1000 watts/m^2 at the best of conditions around the equator. The intermittens means its only producing a third of that on average. So you need 3 square kilometers of solar panels to produce the same amount of energy as a average sized reactor. That is assuming if they are in sahara and have 100% energy conversion. In reality we are talking anything from 10-300 square kilometers depending on location in the world and efficiency of the conversion.

Now consider that solar panels require exotic metalls like germanium, Tellurium ect that offcourse need to be mined, mining those have in general a larger environmental impact than mining uranium because of less concetration in the ore. Factor that in and solar power isn't all that environmental, especially not considering the need for a backup because of its intermitten nature.

Solar power is no more "free" than uranium is "free".

Wave power however has a huge potential, wind perhaps as well but the experience so far from denmark and germany isn't very encouraging. But the environmental impact of nuclear power is already as small as the impact from vind and hydro. With closed fuel cycles the environmental impact would further be reduced by orders of magnitude.
 
  • #45
baywax said:
As for hydrogen production, solar power is a "free" source of energy, wind and hydro are as well. What's more is the fact that we tend to make leaps in technological discoveries and this is one area where we can use a few. Remember that most computers used to need a warehouse to contain them and that your mobile phone used to be the size of an AK7. I have the feeling that there is an efficient and cheap method of hydrogen extraction just waiting to make someone a lot of money.

Well, yes, it's possible. But nuclear power is here now and switching to building nuclear plants instead of coal-fired or oil-fired plants would confer immediate environmental benefits. If you would depend on a nebulous possibility that we might, some day, achieve an efficient and cheap method of hydrogen production, why not depend on a bet that we're going to find a cheap, efficient solution to nuclear waste at some point in the future?

baywax said:
Sorry to get off the topic, inadvertently. I am particularly interested in the safe mining and storage of nuclear material since I was one of many who helped to instill a 28 year long moratorium on uranium mining in my province.

I sympathize in some ways with people who oppose the construction of nuclear reactors - but it doesn't make any sense to me at all why someone would oppose the mining of uranium. I mean… isn't mining uranium basically the same thing as cleaning up nuclear waste that's freely present in the environment and containing it?

And even besides that… surely coal or oil or whatever else is used to produce power, instead of nuclear reactors, wherever you live is just as environmentally damaging, if not more so to mine compared to uranium?

What was the perceived benefit of prohibiting uranium mining? A moratorium actually seems like it might benefit whoever held the mineral rights, if it defers mining to a point in the future where uranium is more scarce on the world market.
 
  • #46
CaptainQuasar said:
Well, yes, it's possible. But nuclear power is here now and switching to building nuclear plants instead of coal-fired or oil-fired plants would confer immediate environmental benefits. If you would depend on a nebulous possibility that we might, some day, achieve an efficient and cheap method of hydrogen production, why not depend on a bet that we're going to find a cheap, efficient solution to nuclear waste at some point in the future?



I sympathize in some ways with people who oppose the construction of nuclear reactors - but it doesn't make any sense to me at all why someone would oppose the mining of uranium. I mean… isn't mining uranium basically the same thing as cleaning up nuclear waste that's freely present in the environment and containing it?

And even besides that… surely coal or oil or whatever else is used to produce power, instead of nuclear reactors, wherever you live is just as environmentally damaging, if not more so to mine compared to uranium?

What was the perceived benefit of prohibiting uranium mining? A moratorium actually seems like it might benefit whoever held the mineral rights, if it defers mining to a point in the future where uranium is more scarce on the world market.

All valid points. The moratorium was about how the tailings from the uranium mine might pose a problem to people who like to drink water in the area.

I think any mining today beats the mess created by tar sands oil extraction.
 
  • #47
Azael said:
Uranium is already mined safetly and to high environmental standards in Australia and Canada. Its really no worse than other kinds of mining.

There is one simple thing that limits solar power that no technology can change. Its incredibly diluted. About 1000 watts/m^2 at the best of conditions around the equator. The intermittens means its only producing a third of that on average. So you need 3 square kilometers of solar panels to produce the same amount of energy as a average sized reactor. That is assuming if they are in sahara and have 100% energy conversion. In reality we are talking anything from 10-300 square kilometers depending on location in the world and efficiency of the conversion.

Now consider that solar panels require exotic metalls like germanium, Tellurium ect that offcourse need to be mined, mining those have in general a larger environmental impact than mining uranium because of less concetration in the ore. Factor that in and solar power isn't all that environmental, especially not considering the need for a backup because of its intermitten nature.

Solar power is no more "free" than uranium is "free".

Wave power however has a huge potential, wind perhaps as well but the experience so far from denmark and germany isn't very encouraging. But the environmental impact of nuclear power is already as small as the impact from vind and hydro. With closed fuel cycles the environmental impact would further be reduced by orders of magnitude.

Yes the extraction methods such as using acids or arsenic are not good. These tailings can damage major areas of wilderness and populated areas as well. You are making a very squeaky clean image of Nuclear power especially calling it less damaging than hydro. I'm trying to remember a whole town like Chernobyl being irradiated and wiped out by a hydro dam. I suppose the technology has come quite a ways since then. But, its not the technology at fault here, its the people using it and their lack of attention to details like those found in environmental issues.
 
  • #48
baywax said:
You are making a very squeaky clean image of Nuclear power especially calling it less damaging than hydro. I'm trying to remember a whole town like Chernobyl being irradiated and wiped out by a hydro dam.

It sounds like you're Canadian. Did you read the CANDU report about Chernobyl? I think http://canteach.candu.org/library/19910101.pdf" . (I live in the U.S. but that happens to be the first engineering report I read about Chernobyl.) It was a seriously careless reactor design.

Do you know how many Soviet space missions simply blew up on the launch pad? They had some major accomplishments but they took a kind of trial-and-error approach to engineering. From what I've read about when they started trying to manufacture their own microprocessors in the 1970's, each chip would get shipped with a list of instructions that didn't work because the manufacturing tolerances were so poor - almost every processor was unique. Whoever received the chip and built a computer around it would have to rewrite all of their software to avoid using the faulty instructions. Eventually they just gave up and started importing Western hardware.

You might know that while U.S. ICBMs are armed with a single high-yield warhead, Soviet/Russian missiles have a large number of smaller warheads. They had to do this because a fair number of the warheads were duds and if they only used one they couldn't be sure it would detonate.

I wouldn't say that nuclear power is squeaky clean but with hydro entire towns get wiped out just building a hydro dam. Way more than that, in fact - The Three Gorges dam which will be the largest in the world is going to http://en.wikipedia.org/wiki/Three_Gorges_Reservoir_Region" (and of course drown forests and a variety of other habitats.)
 
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  • #49
baywax said:
Yes the extraction methods such as using acids or arsenic are not good. These tailings can damage major areas of wilderness and populated areas as well. You are making a very squeaky clean image of Nuclear power especially calling it less damaging than hydro. I'm trying to remember a whole town like Chernobyl being irradiated and wiped out by a hydro dam. I suppose the technology has come quite a ways since then. But, its not the technology at fault here, its the people using it and their lack of attention to details like those found in environmental issues.

Well there are hydro accidents that are worse than Chernobyl. Google for Banqiao Dam disaster, by far the worst industrial accident ever. Close to 200 000 deaths, 6 million buildings destroyed and 11 million people affected.

Tailings "can" damage large areas, but if mining is done correctly Like in Australia and Canada it doesnt. Mining done in any western country has to live up to stringent environmental laws.

Plenty of life cycle assesments have been made for different energy source and nuclear is every bit as good as wind and hydro and its better than solar and biomass. If you got acess to peer review journals take a look at these two articles.

Mark A.J. Huijbregts et al, ECOLOGICAL ECONOMICS, 64 (2008), 798–807
M Rashad, Applied Energy, 65 (2000), 211-219.

ExternE is also very interesting to look at and everything is published on externe's homepage
www.externe.info
 
  • #50
Azael said:
...There is one simple thing that limits solar power that no technology can change. Its incredibly diluted. About 1000 watts/m^2 at the best of conditions around the equator. The intermittens means its only producing a third of that on average. So you need 3 square kilometers of solar panels to produce the same amount of energy as a average sized reactor. That is assuming if they are in sahara and have 100% energy conversion. In reality we are talking anything from 10-300 square kilometers depending on location in the world and efficiency of the conversion.

Now consider that solar panels require exotic metalls like germanium, Tellurium ect that offcourse need to be mined, mining those have in general a larger environmental impact than mining uranium because of less concetration in the ore. Factor that in and solar power isn't all that environmental, especially not considering the need for a backup because of its intermitten nature.

Solar power is no more "free" than uranium is "free".
Well said solar is not free. Keep an eye though on http://www.futurepundit.com/archives/002789.html" . 60% efficient, no exotics, very cheap. In that case setting up a couple of 400 sq km arrays in, say, the vastness of the mojave or Texas somewhere, or even in the big ocean deserts might fly. Still need to find a way of keeping the cells clean at that scale.
 
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  • #51
mheslep I don't know if it's the same thing you're talking about but a recent development - only commercialized in the last year or two - is thin-film solar cells. They basically use modern printing techniques to simply print solar cell circuits on an aluminum or other metal substrate, using no silicon at all, which drastically cuts the cost - by more than a third usually, I think, and even more importantly makes them considerably less fragile - they don't crack or shatter like silicon-based solar cells.

The prediction I've heard is that pretty soon every flat surface that gets sunlight - car roofs, semi trailer roofs, building walls and roofs - is soon going to be covered in solar panels, because why waste the sunlight when solar cells are cheap and physically flexible?

Check out this web brochure from a manufacturer:

http://www.powerfilmsolar.com/technology/index.htm

And this US DoE info page:

http://www1.eere.energy.gov/solar/thin_films.html

I believe all the manufacturers of this stuff are currently backordered for more than they can produce.

[EDIT]Oops, I just noticed that the brochure I linked to actually has the product using a polymer substrate and an amorphous silicon semiconductor. Oh, well - looks like the same lightweight manufacturing technology and flexible result I was talking about.
 
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  • #52
CaptainQuasar said:
mheslep I don't know if it's the same thing you're talking about but a recent development - only commercialized in the last year or two - is thin-film solar cells. They basically use modern printing techniques to simply print solar cell circuits on an aluminum or other metal substrate, using no silicon at all, which drastically cuts the cost - by more than a third usually, I think, and even more importantly makes them considerably less fragile - they don't crack or shatter like silicon-based solar cells.

The prediction I've heard is that pretty soon every flat surface that gets sunlight - car roofs, semi trailer roofs, building walls and roofs - is soon going to be covered in solar panels, because why waste the sunlight when solar cells are cheap and physically flexible?

Check out this web brochure from a manufacturer:

http://www.powerfilmsolar.com/technology/index.htm

And this US DoE info page:

http://www1.eere.energy.gov/solar/thin_films.html

I believe all the manufacturers of this stuff are currently backordered for more than they can produce.

[EDIT]Oops, I just noticed that the brochure I linked to actually has the product using a polymer substrate and an amorphous silicon semiconductor. Oh, well - looks like the same lightweight manufacturing technology and flexible result I was talking about.
DOE says they hope to thin films up to 10% efficient, or ~100W / M^2. - a bit tough to make a central power plant.
 
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  • #53
mheslep said:
DOE says they hope to thin films up to 10% efficient, or ~100W / M^2. - a bit tough to make a central power plant.

Would even 100% efficient really get you anywhere? I remember the CEO of Exxon-Mobil saying that it would take a surface of solar cells the area of New Jersey to equal the energy output of an average gas station. I didn't check those numbers - perhaps someone would like to work them out and see if this was total b▒▒▒▒▒▒t artistry - but it doesn't sound entirely off the mark to me. Even if you could equal a gas station's output with an acreage a tenth or a twentieth, or even a fiftieth of the area of New Jersey, dealing with time in the shade and everything, it seems like solar cells will never be more than a supplemental energy source.
 
  • #54
I ran the numbers: Energy content of gasoline: 36.3 kilowatt-hrs / US gallon. Average gas station pumps 5000 gal / day = 181 megawatt-hours every day. Assuming good solar collection averages 10 hrs (?), the equivalent solar array has to have an average power 18 MW for 10 hrs. Solar irradiance is ~1KW/M^2 so at 100% efficiency you need 18,000 M^2 of arrays, or 0.14km on a side; at 60% 0.17km on a side; at 10 % about 0.5km or 0.25 km^2. How about for the gas needs of the whole state? Avg state has 2300 gas stations in the US = 575 km^2 of solar to produce enough electrical power for the equivalent of all the gasoline pumped every day. NJ btw is 22600 km^2, so 2% of NJ (1/50 as you say!) has to move over to convert from gas to 10% efficient solar. IF the solar array is 60% efficient then you need only 66km^2 or ~9x less area. Out in a state like Tx or Ok you'd probably never know the array was there, put it in some big rancher's field.

Probably need another 2x in here for weather and distribution losses.
 
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  • #55
You live somewhere that's sunny for 10hrs every single day? I should move there. Before all the shady areas are covered with solar panels and all of the vegetation consequently dies. (Also, I think you might be a bit optimistic to be making calculations directly off of the total solar irradiance - working off of the actual production of solar arrays might produce lower numbers, I would suspect.)

But if you're right, and the power output of all the gas stations in a single state could be replaced with the solar output of one rancher's field (or nine rancher's fields at the current level of technology? Why are they bothering extracting and refining petroleum in Texas right now?) then I look forward to an extremely energy-rich future. Forget rancher's fields, you could easily float a solar array of any size off the coast anywhere in the U.S.
 
  • #56
CaptainQuasar said:
But if you're right, and the power output of all the gas stations in a single state could be replaced with the solar output of one rancher's field (or nine rancher's fields at the current level of technology? Why are they bothering extracting and refining petroleum in Texas right now?) then I look forward to an extremely energy-rich future. Forget rancher's fields, you could easily float a solar array of any size off the coast anywhere in the U.S.
Simple: solar panels are expensive. Being generous, if they cost you $2 per watt, that's $800 billion, just for the panels themselves. And for that, you haven't installed them, wired them, motorized them, converted their DC power to AC, kept them clean, or done an environmental impact study on the effect of blotting out the sun for such a large area.
 
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  • #57
russ_watters said:
Simple: solar panels are expensive. Being generous, if they cost you $2 per watt, that's $800 billion, just for the panels themselves. And for that, you haven't installed them, wired them, motorized them, converted their DC power to AC, kept them clean, or done an environmental impact study on the effect of blotting out the sun for such a large area.

Numbers like that actually aren't so daunting - I mean, that's not http://www.cnn.com/2008/US/03/10/iraq.costs.ap/index.html" , right? Does that really compare unfavorably to petroleum prospecting, extraction, and refining infrastructure? (Or plus the transport infrastructure, if you count the fact that we already have a national and international transport grid for electricity generated from other sources.)

russ, do you think that solar could workably serve as a primary source of power as mheslep is suggesting? That seems like it would be pretty nice, actually, if it truly has that potential. But even as an omnipresent supplementary source of power, which I'm suspecting it might be relegated to practically, wouldn't be too bad.
 
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  • #58
baywax said:
As for hydrogen production, solar power is a "free" source of energy, wind and hydro are as well. What's more is the fact that we tend to make leaps in technological discoveries and this is one area where we can use a few. Remember that most computers used to need a warehouse to contain them and that your mobile phone used to be the size of an AK7. I have the feeling that there is an efficient and cheap method of hydrogen extraction just waiting to make someone a lot of money.

This is always the problem with the "ecologist's" opposition to nuclear power: they want to replace actual technology by dream technology. Of course dream technology is going to be better. Before you can propose on a large scale any industrial process, the fundamental research needs to be already done. You cannot base real-world strategies in the middle long term on the anticipation of fundamental research results that simply aren't there yet, and maybe never will be. It is what is happening in Germany: they are phasing out nuclear power, and wanted to replace it by wind power and other renewables.
IN PRACTICE, they are replacing it with coal power plants, simply because dream technology only works on paper and powerpoint presentations, but not with real power plugs.
So, in practice, they are making an ecological step backwards.

As to fuel cells, you don't need fuel cells to make electricity from hydrogen. If you already have the hydrogen, you can BURN it in gas turbines. THAT's an existing technology, which is moreover rather clean. So if you have the hydrogen, then the energy problem IS already solved. However, the only KNOWN way to produce hydrogen in industrial quantities is... by electrolysis of water ! (or by other chemical processes which are at least as energy-consuming, like having metals react with acids in water solution, which is in fact exactly the same reaction, but "in solution")

You see, the "solution" of the power problem with fuel cells is somewhat like proposing as a solution to buy a generator with a diesel engine. But you still need the diesel fuel!

Sorry to get off the topic, inadvertently. I am particularly interested in the safe mining and storage of nuclear material since I was one of many who helped to instill a 28 year long moratorium on uranium mining in my province.

Ah. And you also instilled a moratorium on coal mines ?
 
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  • #59
CaptainQuasar said:
Numbers like that actually aren't so daunting - I mean, that's not even one Iraq War, right?

For the price of one Iraq war, you'd have about 500 nuclear power plants by now, so you'd be all nuclear for the next 60 years or so.
 
  • #60
CaptainQuasar said:
russ, do you think that solar could workably serve as a primary source of power as mheslep is suggesting? That seems like it would be pretty nice, actually, if it truly has that potential. But even as an omnipresent supplementary source of power, which I'm suspecting it might be relegated to practically, wouldn't be too bad.

For the moment, solar power is still far too expensive to be competitive with nuclear generated electricity (which is the cheapest form of electricity production as of now, waste management included). However, wind energy is only about twice as expensive, and hence, it can be considered.

But these two sources have similar problems:
the size of the installations (and hence their ecological impact), and the intermittency of their production. Don't forget that there is a big factor between installed (maximum) power, and effective, average power. For wind energy in favorable places, this is a factor of about 6, and I think a similar factor for solar.

So even if one decided to go "all solar" and "all wind", you'd have to have a need for (fossile?) backup capacity that is of the same order as the full installation, with high flexibility ; in fact, only gas turbines can cope.

So this means that in the EFFECTIVE cost of such a solar/wind installation, you need to include the price of a SECOND complete power system, which moreover is based upon fossile fuel and which will probably be used for only a few tens of percents of its full capacity on average.

You don't see that in marginal cost calculations as long as you have minority contributions, because you are "stealing" flexibility from the majority system. Denmark is an example: about 20% wind energy, and almost totally relying on the flexibility of the German and Swedish power production, who compensate for the variability of the production. If they would be on their own, and they would go to 60% wind energy, then the cost of wind energy would drastically increase.
 
  • #61
baywax said:
I'm trying to remember a whole town like Chernobyl being irradiated and wiped out by a hydro dam. I suppose the technology has come quite a ways since then. But, its not the technology at fault here, its the people using it and their lack of attention to details like those found in environmental issues.

You really really cannot compare Chernobyl (and the entire Soviet industry policies) with western countries.
But even so, place Chernobyl in context:
- a few hundred direct dead
- an estimated 10 000 victims of pollution over the next 50 years (where do you have reports of the estimated number of victims of pollution over the next 50 years of other catastrophes, or even technologies, like coal power plants ?)
- an area of about 1000 km^2 contaminated and hence transformed into natural park for about 200 years.

That said, if accidents of the Soviet era are the point of comparison, then you should look at how many coal mine dead they had per year, and find out if coal mining is acceptable, how much pollution they had from any industry they had, and whether that is acceptable, how safe cars are etc...

So, really, Soviet technology and accidents are not a measure for the expected risk of a given technology - at most it can serve as a worst-case simulation!
 
  • #62
russ_watters said:
Simple: solar panels are expensive.
Exactly.
 
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  • #63
vanesch said:
You really really cannot compare Chernobyl (and the entire Soviet industry policies) with western countries.
But even so, place Chernobyl in context:
- a few hundred direct dead
- an estimated 10 000 victims of pollution over the next 50 years (where do you have reports of the estimated number of victims of pollution over the next 50 years of other catastrophes, or even technologies, like coal power plants ?)
- an area of about 1000 km^2 contaminated and hence transformed into natural park for about 200 years.
Yes there is a paper out, can't find it at the moment, about a couple of researchers/biologists who went over in 200x to study the effects of Chernobyl in the immediate area. They state that they were expecting to find a radiological disaster and were instead chagrined to discover that the effects were basically nil for the plant and animal life 20 yrs out. Edit: Here's a similar piece in Nature News: http://www.nature.com/news/2005/050808/full/news050808-4.html
 
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  • #64
CaptainQuasar said:
Numbers like that actually aren't so daunting - I mean, that's not http://www.cnn.com/2008/US/03/10/iraq.costs.ap/index.html" , right?
Well, once you factor in all the other costs, it probably puts the numbers roughly equal to each other, probably $5 a watt, conservatively. That also doesn't include the fact that you get probably about a 30% utilization factor from it. So compared with a source that runs 24 hours a day, that's $15 a watt.

Costs will certainly come down, but here's a recently built plant that cost $7/W: http://www.metaefficient.com/news/north-americas-largest-solar-electric-plant-in-switched-on.html

Note the simple payback on the project is a hundred years if you don't include maintenance and assume the solar panels will last that long.

You could compare that with nuclear, currently estimated at an installed cost of $1.85 per watt. So you're 3-5 times the cost of nuclear, and that's including current regulations that make nuclear power more difficult than it needs to be.

http://www.washingtonpost.com/wp-dyn/content/article/2005/07/23/AR2005072300752.html
Does that really compare unfavorably to petroleum prospecting, extraction, and refining infrastructure? (Or plus the transport infrastructure, if you count the fact that we already have a national and international transport grid for electricity generated from other sources.)
The comparison is not easy because the operating cost for nuclear and solar are both low, but for fossil fuels, the construction costs are a good order of magnitude lower. And that's a big hurdle. Here's a recently built gas turbine plant that cost $0.5 / watt to construct: http://www.bizjournals.com/dallas/stories/2001/07/16/story2.html

I don't know what they pay for natural gas, but if it's $8 per million btu (that number may be wholesale - it could be more like $15) and the plant has a 40% thermodynamic efficiency, that's $0.6 per watt per year.

http://tonto.eia.doe.gov/oog/info/ngw/ngupdate.asp
russ, do you think that solar could workably serve as a primary source of power as mheslep is suggesting? That seems like it would be pretty nice, actually, if it truly has that potential. But even as an omnipresent supplementary source of power, which I'm suspecting it might be relegated to practically, wouldn't be too bad.
No, I really don't see how it could. It isn't just the money for the plant, land is valuable and people are not going to want to give it up. Environmentalists included.
 
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  • #65
vanesch said:
Don't forget that there is a big factor between installed (maximum) power, and effective, average power. For wind energy in favorable places, this is a factor of about 6, and I think a similar factor for solar.
I used a factor of 3 in my calculation, but that is admittedly conservative. It may be doable in the desert, though.
 
  • #66
vanesch said:
...So even if one decided to go "all solar" and "all wind", you'd have to have a need for (fossile?) backup capacity that is of the same order as the full installation, with high flexibility ; in fact, only gas turbines can cope...
Well if the average solar/wind power is sufficient, there are some good storage techniques available that can handle the lulls, pump-storage in particular.
 
  • #67
russ_watters said:
Costs will certainly come down, but here's a recently built plant that cost $7/kW: http://www.metaefficient.com/news/north-americas-largest-solar-electric-plant-in-switched-on.html...
Article says that Nellis AFB plant is 14MW on 140acres (0.57 sq km), or only 25W/sq M, ouch. Thats 4X worse than my worse case guess above (100W/sq M), so now we're up from 2% to 8% of NJ under glass, and that's sunny Nevada. Perhaps this lower than expected result is due to dead space over that 140acres.

Edit: With regards to the cost and payback time: Currently solar never pays back, though solar PV is not that far out of reach. Its currently 2-3X more expensive IF the land is free (already owned, as at Nellis). (The article is confusing - the AF didn't pay the $100M and thus the 2.2c/kw-hr is meaningless). Solar PV costs ~http://www.solarmarket.com/products.html" now and fossil is 9 to 10 (in say Nevada). Cost of solar is almost all amortization of investment, cost of fossil is currently 1/2 to 2/3 investment and the remainder fuel costs. So to make solar PV viable either one of two things needs to happen: PV doubles in efficiency per cost and that's looking plausible, or fossil fuel increases in cost by 2 to 3x also looking plausible. I imagine there's already tax advantages in place to help solar along, and there's likely environmental penalties increasing on fossil plants to raise its cost.
 
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  • #68
vanesch said:
Ah. And you also instilled a moratorium on coal mines ?

I don't know anything about coal. In fact I haven't the foggiest about uranium. Perhaps that's one of the problems. Education.

My guess is that there is a big scare about nuclear power because the only thing (most) people know about "nuclear energy" is that it results in a very big mushroom cloud. Then people's skin falls off or there's nothing left of them but a shadow on the ruins of a building.

If there can be nationally funded education and town meetings about nuclear energy that are not just propaganda but show all sides of the issue, including the methods of waste disposal, effluent hot water, mining techniques that work and that don't work with the environment... then people might get a little cozier about the idea of reading by the light of the nuclear power plant.

Right now I believe there is a rather large mushroom cloud looming over the industry in most people's uninformed minds.
 
  • #69
mheslep said:
Well if the average solar/wind power is sufficient, there are some good storage techniques available that can handle the lulls, pump-storage in particular.

You mean, reversible hydro ?
Point is, you need a big capacity to compensate for a windless week in winter when it is cloudy !
 
  • #70
vanesch said:
You mean, reversible hydro ?
Point is, you need a big capacity to compensate for a windless week in winter when it is cloudy !
Yes exactly. This is a 2100MW facility:
http://www.dom.com/about/stations/hydro/bath.jsp
I walked the flow tunnels at that plant before they turned it on. Pumps the water up at night when there's excess power, and generates during the day when there's high demand.

Edit: I note that recently just by retooling the turbines to current technology the facility is jumping to 2700MW.
 
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