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Construction Costs:
Nuclear: $14 billion (Vogtle units 3 & 4) https://en.wikipedia.org/wiki/...
Solar: $2.2 billion (Ivanpah Solar Power Facility) https://en.wikipedia.org/wiki/...
Wind: $1.5 million (typical 1 megawatt windmill in USA) https://emp.lbl.gov/sites/all/...

Power produced:
Nuclear: 2 GW (2 units x 1.2 gigawatts each x 0.85 expected capacity factor)
Solar: 80 MW (400 MW capacity x 0.2 measured capacity factor)
Wind: 0.33 MW (1 MW x 0.33 typical measured capacity factor)

Expected Operational Lifespan:
Nuclear: 60 years
Solar: 25 years
Wind: 20 years

CO2 emissions: https://web.archive.org/web/20...
Nuclear: 60 g/kWh
Solar: 40 g/kWh
Wind: 21 g/kWh

Someone check my math but this is what I came up with. Wind produces 1/3rd the CO2 of nuclear but costs twice as much. Solar produces 2/3rds the CO2 but costs *TEN TIMES* as much. I'm taking into account installed capacity, operational lifespan, and capacity factor. You can take into account things like cleanup costs after the power plant is retired, lifetime operational costs, etc. Some people just love to point out the extreme costs of building a nuclear power plant but if the actual potential for producing power is taken into account it looks real cheap.

Trying to find actual historical costs of energy of these energy sources has been difficult. Lots of people like to "estimate", "project", or just plain leave things out of their study. A study by what people might assume to be biased pro-nuclear shows electricity costs around the world: https://www.oecd-nea.org/ndd/p... It shows solar to be quite expensive compared to anything else in the study.

By my estimates wind and nuclear really win out here. Solar might look marginally better than nuclear for reducing CO2 but the costs are just outrageous.

No, that's not really true. Nuclear can and is operated in a load following manner in e.g. France and even Germany... You can really ramp up and down on a dime, as it were, i.e. there's no technical reason not to.

The reason it isn't too popular is instead that nuclear is a capital expense heavy operation, with low (relatively speaking) operating costs. So if you've built a nuclear plant you want to run it as close to 24/7 as possible, as anything else would be uneconomical.

And that's the problem with renewals, they're eating nuclear's lunch. That is, they're happy to skim the cream off the top, delivering when they can and selling dearly then, while not being able to deliver when it counts. In doing so having taken a big chunk of the money we need to make nuclear financially viable.

P.S. Smart grids are a canard. In Sweden we use our electricity for industry, and we should use a lot more for transportation. Switching water heaters on and off on a whim doesn't make one iota worth of difference.

Neutrons don't usually cause double strand breaks in DNA. Alpha particles are much more trouble; then betas, then high energy gamma, then lowly neutrons!
Also,
Viewing the nuclear cross sections can be done with the even more powerful tool JANIS
https://www.oecd-nea.org/janis...

Alphas are indeed much more trouble. But also, alphas can be blocked by a piece of paper, while neutrons just keep on sailing through for a good while. My point is that alphas are not a problem in the real world unless you ingest or inhale an alpha-emitter––that is the only way they can cause serious trouble – be being inside you and wrecking whatever cellular matter they are sitting next to.

According to https://www.oecd-nea.org/ndd/r...:

Modern nuclear plans with light water reactors have strong manoeuvring capabilities. Nuclear power plants in France and in Germany operate in load-following mode, i.e. participate in the primary and secondary frequency control, and some units follow a variable load programme with one or two large power changes per day. In France, load-following is needed to balance daily and weekly power variations of the electricity supply and demand, since nuclear power plants have a large share in the national mix. In Germany, load-following became important in recent years when a large share of intermittent sources of electricity generation (e.g. wind) was introduced to the national mix.

The minimum requirements for the manoeuvrability capabilities of the modern reactors are defined by the utilities requirements that are based on the requirements of the grid operators. For example, according to the current version of the European Utilities Requirements (EUR) the NPP must at least be capable of daily load cycling operation between 50% and 100% of its rated power P r , with a rate of change of electric output of 3-5% of P r per minute.

Most of the modern designs implement even higher manoeuvrability capabilities, with the possibility of planned and unplanned load-following in the wide power range and with ramps of 5%P r per minute. Some designs are capable of extremely fast power modulations in the frequency regulation mode with ramps of several percent of the rated power per second, in the narrow band around the power level. The economic consequences of load-following are mainly related to the reduction of the load factor. In the case of nuclear, fuel costs represent a small fraction of the electricity generating cost, if compared with fissile sources. Thus, operating at higher load factors is profitable for nuclear power plants, since they cannot make savings on the fuel cost while not producing electricity. In France, the impact of load- following on the average unit capability factor is sometimes estimated as about 1.2%.

Since most of the currently used nuclear power plants implement strong manoeuvrability capabilities in their designs (except for some very old NPPs), there is no or very small impact (within the design margins) of the load-following on acceleration of ageing of large equipment components. However, there is some influence of the load-following on the ageing of some operational components (e.g. valves), and thus one can expect a slight increase of the maintenance costs. Also, for older plants some additional investment could be needed, especially in instrumentation and control, in order to become eligible for operation in the load-following mode.

Ah, here's what I was looking for. From a US review of spent fuel, http://www.nrc.gov/reading-rm/..., a section entitled

5.1 IMPORTANT ISOTOPES IN SPENT NUCLEAR FUEL SAFETY ANALYSES (p) 31 5.2 (next section) (p)35"

Actually, my guesstimate of "hundreds" above is reduced on that table to a mere 41. Of course, a different authority would probably choose a different group that are "important" but "dozens" certainly seems a good starting estimate.

I found a second source, https://www.oecd-nea.org/scien... which has a similar list of 31 nucleides.

You are full of shit. Load following works fine in nuclear reactors of appropriate design. Modern plants make one or two large changes per day, and are required to be able to cycle daily between 50% and 100% of rated capacity with a rate of change of 3-5% per minute.

Many are rated for several percent change per second.

You are waaay out of touch with technology. Read that report. Look at how often they cycle the power. Load following works fine, and they're required to be able to make these swings for 90% of the fuel cycle--at any point, unplanned.

The waste issue (as well as inherent safety) is part of the reason that there's so much research on ADSRs right now (note: the article says that an ADSR "would use thorium as a fuel", but it's not actually limited to thorium, it can use any subcritical fissile core). Spallation can rip apart the long-lived actinides that don't have a sufficient (n, gamma) cross section to prevent their accumulation in nuclear waste. And of course, since the core is inherently subcritical by design, simply not enough neutronicity under any condition to sustain a chain reaction on its own, when you shut the beam off, fission ceases instantly (though you still have decay heat like with any other nuclear power plant). Spallation source provides no more than about 10% or so of the neutronicity, but it's the amount needed to push the core over the edge.

I have my own very radical variant on the concept of an accelerator driven fission that I'm working on simulating now in Geant4 (although that was probably a poor choice of software, apparently their thermal scattering codes are really immature... as far as CERN is concerned, once particles get down below the MeV range they're usually not particularly interesting). But anyway the concept is to have a core with literally zero neutronicty - a lithium-burning reactor. The basic concept is as such:

1. A planar proton beam is delivered by one or more high power linac beamlines. Commercial-scale linac costs - without any improvements in technology - are expected to cost $5-20 per watt. The particular design would call for very high voltage (~16MV) klystrons to drive it - and not simply to reduce size (more in this shortly)

2. The proton beam bombards a fragment emitting target inside an axial magnetic field in a vacuum. The estimation of deceleration efficiency is estimated at over 90% in fragment reactors due to the lack of Carnot losses (according to the published research on the subject). The resultant HVDC will be direct converted to the klystron voltage in producing the electron beam that drives the linac. About 60% of the energy of spallation goes into fragment production. Fragments will be drawn away from the fragment target en route to the collector via a slightly expanding axial magnetic field. Fragment collection allows for automatic isotope separation.

3. The maximum power output of a fragment reactor is limited by its surface area and its ability to radiate heat. Fragment-emitting targets can be either electrostatically suspended dust or rapidly rotating with thin fibers or planes of target material, in order to radiatively cool without melting. Spallation targets, for efficiency, need to be high-Z materials, such as lead, tungsten, mercury, etc. Tungsten is particularly attractive due to its high melting point of 3695K. High-Z metal-rich ceramics are also possible targets, with very high melting points. The temperature of the chamber's beryllium walls being radiated to will be around 1050K. This means heat exchange between a ~3000K emitter (4.6e7W/m) and a 1050K receiver (6.8e4W/m), or about 4.5MW per square meter. In short, this allows for a surprisingly compact core, limited more by the length necessary to ensure a sufficient proton spallation cross section.

4. Neutrons emitted by spallation (at a cost of 30-40 MeV per neutron) are heavily biased by

Because I try not to respond to ACs, I'll stick it in here.

As you pointed out, Nuclear ships DO NOT run their plants at 'full power all the time'.

But even HUGE nuclear plants can be built to be capable of 'load following', going from 100% down to 50% and below on a consistent basis. France has a number of them.

Part of the problem with using reactors for load-following is that all the reactors in the USA are very old Gen-II designs, you need to be at least 'newer' Gen-II to do a lot of load following, and we don't have enough nuclear for them to NEED to load-follow, leaving them as the cheapest margin for on-demand power.

If we went from our current mix of about 20% nuclear, 40% coal, to a carbon-neutral mix of 40% nuclear, 20% solar, 20% wind, and 20% 'other, including hydro', you'd have most of your peaking power in 'other', but nuclear power would still have to adjust for peaking.

30-100% load cycling, according to Wikipedia: http://en.wikipedia.org/wiki/L...

Also this link: http://www.oecd-nea.org/nea-ne...

Much depends on the exact reactor type, but for Gen II PWR/BWR reactors and up load-following is most definitely a realistic proposition. As the second link notes, German reactors were forced to switch to load-following mode due to the disruptions on the grid caused by the large-scale unbuffered PV solar and wind turbine fluctuations on the grid.

your information is outdated, as is that Wikipedia entry. I'll try to update it after this post.

The quote below is from "Nuclear Development, June 2011, http://www.oecd-nea.org/"

"Modern nuclear plants with light water reactors are designed to have strong maneuvering capabilities. Nuclear power plants in France and in Germany operate in load-following mode, i.e. they participate in the primary and secondary frequency control, and some units follow a variable load programme with one or two large power changes per day.

The minimum requirements for the maneuverability capabilities of modern reactors are defined by the utilities requirements that are based on the requirements of the grid operators. For example, according to the current version of the European Utilities Requirements (EUR) the NPP must at least be capable of daily load cycling operation between 50% and 100% of its rated power Pr, with a rate change of electric output of 3-5% of Pr per minute.

Most of the modern designs implement even higher maneuverability capabilities, with the possibility of planned and unplanned load-following fast power modulations in the frequency regulation mode with ramps of several percent of the rated power per second, but in a narrow band around the rated power level."

the above excerpt is just a small portion of http://www.google.com/url?sa=t...

I'm not sure why the URL has to be so god awful long to work, I tried to shorten it manually but it killed the link. I suppose if I could find a direct link from http://www.oecd-nea.org/ it might be shorter but I'm not in the mood to dig for it.

your information is outdated, as is that Wikipedia entry. I'll try to update it after this post.

The quote below is from "Nuclear Development, June 2011, http://www.oecd-nea.org/"

"Modern nuclear plants with light water reactors are designed to have strong maneuvering capabilities. Nuclear power plants in France and in Germany operate in load-following mode, i.e. they participate in the primary and secondary frequency control, and some units follow a variable load programme with one or two large power changes per day.

The minimum requirements for the maneuverability capabilities of modern reactors are defined by the utilities requirements that are based on the requirements of the grid operators. For example, according to the current version of the European Utilities Requirements (EUR) the NPP must at least be capable of daily load cycling operation between 50% and 100% of its rated power Pr, with a rate change of electric output of 3-5% of Pr per minute.

Most of the modern designs implement even higher maneuverability capabilities, with the possibility of planned and unplanned load-following fast power modulations in the frequency regulation mode with ramps of several percent of the rated power per second, but in a narrow band around the rated power level."

the above excerpt is just a small portion of http://www.google.com/url?sa=t...

I'm not sure why the URL has to be so god awful long to work, I tried to shorten it manually but it killed the link. I suppose if I could find a direct link from http://www.oecd-nea.org/ it might be shorter but I'm not in the mood to dig for it.

No containment can contain a meltdown, if it wasn't built to do so. The BWR containments, as used in Fukushima Daiichi, just weren't, because it wasn't deemed necessary. Nureg/CR-6042 made it pretty clear that the focus back in the early 1960ies was on definitively preventing "catastrophic deaths". Preventing contamination just wasn't the goal. From the perspective they had, it was sufficient if meltdowns were unlikely. This has changed, but at least in the US and Japan, the power plants weren't changed to accomodate this.

And I'm not cherrypicking my sources. Any of the well known and often discussed reports like Wash-1400 or Nureg-1150 make it very clear that such BWR containments would overpressurize and leak soon after a meltdown due to hydrogen generation (hydrogen can't be condensed, unlike water steam), leading to widespread contamination after a meltdown. That's not merely a chance, but a certainty. (Whether a meltdown can be prevented is a different matter.) All three also clearly state that flooding and tsunamis (in Wash-1400 "tidal waves") are a potential cause for a meltdown, despite the redundancy of safety equipment, because they cause a full station blackout.

All this is quite different in other containments. Pressure water reactors typically have a large dry containment, that is capable of containing a meltdown, at the very least long enough for most contaminants to settle down in the containment and not outside of it. (Without power to run any pumps, it takes some 20 hours for 99% of the Cesium to settle down. With power, you can run containment sprays and do it in a bit more than half an hour. BWR Mark I/II containments generally don't have such sprays.) Newer BWR containments are also much larger and much more capable of containing a meltdown.

Other countries such as Sweden, France and Germany fitted filtered containment vents to their nuclear power plants in 1980(Sweden) and 1988 (Germany/France). Which would have prevented any significant fallout, because the containments wouldn't overpressurize.

Cost of nuclear station subsidy £96-£97 per megawatt hour
http://www.independent.co.uk/n...

Cost of wind
£100 per megawatt hour
http://www.telegraph.co.uk/ear...

Cost wise they are about the same.

  Currently in countries such as South Korea and China, typical construction times range from 4 to 6 years
https://www.oecd-nea.org/press...

Construction time is usually very short – a 10 MW wind farm can easily be built in two months. A larger 50 MW wind farm can be built in six months.
http://www.ewea.org/wind-energ...

Add in the time for planing etc and wind is faster.

http://www.oecd-nea.org/html/rp/chernobyl/chernobyl-figure6.pdf

The consequences of Fukushima are a direct result of the power station being unchanged since the 1970ies, even though it became clear already in that decade, that safety precautions were insufficient. Especially concerning the risk of hydrogen explosions (hydrogen was already a known problem during the Three Mile Island accident in 1979), the lack of autocatalytic recombiners (which prevent them) and the lack of filtered containment vents - which were installed in both Germany and France (which you mention here) in the 1980ies and 90ies, in anticipation of otherwise unacceptable releases during a meltdown.

Here are the figures for radioactivity released from Chernobyl for comparison. Interestingly, Cs-137 makes up less than 8% of the radioactivity (becquerels, or radioactive emissions per second), but 58% of the total radiation released (becquerel * half-life, or total emissions over the radionuclide's lifetime), with the relatively benign (compared to Cs-137) plutonium radionuclides being the second biggest chunk at 25%, most of it spread over a 24k year half-life.

According to the paper, Fukushima released about 2.5x more Xe-133 than Chernobyl, but with a half life of just 5.3 days most of that decayed while over the ocean. Overall emissions looks to be about 1/3rd that of Chernobyl with most of it falling in the sea, with Cs-137 accounting for nearly all of the long-term contamination unlike Chernobyl.

All because some bozos at TEPCO wanted to try to salvage the plant and delayed dumping seawater into the core to prevent the zircaloy cladding from melting.

According to the Nuclear Energy Agency the majority of the radioactivity released at Chernobyl was in Xenon-33 with a half-life of 5 days. This was followed by Iodine-131 (half-life 8 days) and Tellurium-132 (half-life 78 hours). The next most active element released (measured in Becquerels) was only 3% of the Xenon released, and it has a half-life of 13 days.

If I read the report from the NEA correctly then ISTM I was comparing apples to apples.

Furthermore, unless one or more of the reactor cores at Fukushima has gone critical again after the shutdown then any direct product of the fission reactions that has a half-life measured in minutes was gone after the first day of the accident, well before the meltdowns and hydrogen explosions and measured releases of significant amounts of radioactivity.

There are certainly very short-lived isotopes that are part of the decay chain of long-lived isotopes. Iodine-131 is a perfect example. The problem is that they will continue to be created for the duration of the longer-lived isotopes.

Yeah they conveniently forget that this was never the problem at Chernobyl. Both Iodine and Cesium are only dangerous if you ingest significant quantities of them. Additionally they have halflives measured in hours ... Meaning these clouds are completely harmless after half a day passes.

The problem at Chernobyl was release of Uranium and Plutonium in clouds, which then spread around the site, and irradiated everything. They will keep irradiating everything for eons. Soviets managed to vaporize about 3.5% of the reactor fuel (and Uranium does NOT vaporize easily, we're talking thousands of degrees). And made it so freaking hot it could stay afloat for minutes.

Does it really need to be said that the Japanese lost control of exactly 0.00000000000000000000000000000000000% of their nuclear fuel. Wanna bet the author of this story is a "green scientist" ?

The thing is, you need to put things in perspective. Even with the radioactive clouds released, background radiation levels at Fukushima, just outside the reactor building are lower than the natural level of radiation in Ramsar, in Iran (which has a particularly high natural level, it has nothing to do with whatever is currently happening there, it's probably been that way for longer than humans exist). Spending a year close to Fukushima itself will have ZERO observable health effects.

Get some perspective (see left upper corner for the increase in background radiation)

I guess we're seeing populist politicians implement their usual strategy : lie. Sorry, ... "Fake but accurate" is the term, right ?