Is Nuclear Power a Viable Option for Our Energy Needs?
Posted by Prof. Goose on August 8, 2006 - 3:34pm
Topic: Alternative energy
Tags: eroei, light water fission, nuclear, nuclear energy [list all tags]
In the middle of the last year it became clear to me that the Australian Government was interested in having a debate about Nuclear Energy for Australia. I decided that we, in the School of Physics, could make a positive contribution to the debate and organized a study group to investigate this. We constructed a wiki-based website (http://nuclearinfo.net) where we placed our findings. We went live last December but have updated the website as we've learned more about energy issues and Nuclear Power.
In this post I draw heavily on website and restrict myself to talking about light water fission reactors. There are a variety of different and more advanced reactor schemes that could be addressed in a future post. There are more details on our website on all of the topics covered here.
Nuclear Fission Basics
A nuclear fission reaction occurs when a 235U or 239Pu nucleus captures a neutron, splits into two smaller nuclei and releases 2 - 3 more neutrons. These neutrons can be used to initiate further reactions. From an energy standpoint, the significant feature is that the release is around 200 Million Electron Volts per reaction. A typical chemical process such as the oxidation of hydrogen, emits 20 electron volts per reaction. Thus nuclear fission provides around 10 million times more energy than chemical processes. This factor of 10 million sets the scale of Nuclear Power.
Natural Uranium consists of 99.3% 238U and 0.7% 235U. Conventional light water reactors utilize fuel with an initial 235U concentration enriched to at least 3.5%. The energy released from these reactors comes from the fission of 235U and 239Pu (which is produced via neutron captures on 238U). The heat from the reaction is used to drive steam turbines with a conversion efficiency of around 33%. Typically the fuel is loaded at 3.5% 235U and replaced once the 235U concentration has fallen to 1.2%. A 1 GW light water Nuclear Power Plant consumes 30 tonnes of fuel per year. A coal-fired plant of the same magnitude consumes 9000 tonnes of coal per day.
World Uranium supply
Given that this website is devoted to the study of peak oil, I think it's appropriate to first look at the prospects for using Uranium as fuel source for at least the rest of the next century. Uranium is not a particularly rare mineral. It has an average crustal abundance of about 2.7 Parts Per Million (PPM), which about the same as tin and zinc. There is an estimated 40 trillion tonnes of Uranium in the Earth's crust. To date we have mined less than one ten-millionth of this (as opposed to about half the world's conventional crude Oil). A typical 1 GW Nuclear reactor requires around 200 tonnes of natural Uranium per year. Current world consumption of Uranium amounts to some 65,000 tonnes per annum. Current world supply is around 40,000 tonnes per annum. The mismatch is maintained by the drawn-down of stocks and the use of fissile material available from the reduction in Nuclear Weapons in the USA and ex-Soviet Union. The combination caused a decade-long depression of World Uranium price. These stocks and secondary sources will be exhasted by the middle of the next decade. In early 2003 the price of Uranium was $23 per kg, it is currently at around $110 per kg. This price increase has triggered a rapid increase in exploration activity around the world. At $110 per kg, the price of Uranium Ore contributes about 0.22 cents per KW-HR to the price of Nuclear generated electricty.
Reasonably assured reserves (or proven reserves) refers to known commercial quantities of Uranium recoverable with current technology and for a specified price. The terms additional and speculative reserves refer to extensions to well explored deposits or in new deposits that are thought to exist based on well defined geological data.
As of the beginning of 2003 World Uranium reserves were:
- Reasonable Assured Reserves recoverable at less than $US130/kgU (or $US50/lb U3O8) = 3.10 - 3.28 million tonnes.
- Additional reserves recoverable at less than $US130/kgU (or $US50/lb U3O8) = 10.690 million tonnes.
As of the beginning of 2005 World Uranium reserves were:
- Reasonable Assured Reserves recoverable at less than $US130/kgU (or $US50/lb U3O8) = 4.7 million tonnes.
- Additional recoverable Uranium is estimated to be 35 million tonnes
The substantial increase (almost 50%) from 2003 shows the results of the world-wide renewed exploration effort spurred by the increase in Uranium prices which commenced in 2004. This increase in activity has continued through to 2006. Thus, the provable uranium resources amount to approximately 85 years supply at the current level of consumption with current technology, with another 500 years of additional reserves. It is worth noting that the numbers above do not reflect the considerable increase in Uranium exploration that has taken place in 2005 and 2006.
It is interesting to speculate on the ultimate size of the world Uranium resource, if it were to power light water reactors. This can be estimated by comparing the energy produced by a nuclear plant to the energy required to mine and refine the Ore. As one moves to lower grade Ore, the energy cost the mining and refining increases. However the total resource size increases at these higher dilutions. If we assume the rate at which the energy cost increases is inversely proportional to the Uranium concentration in the Ore we can estimate the ultimate size of Uranium resource if consumed in light water reactors. The Rossing mine in Nambia is a large, low grade Ore deposit. It produces around 3000 tonnes of Uranium per year. The energy cost of this process is 1 PetaJoule. Now 3000 tonnes of Uranium provides 15 GigaWatt-years of power which is about 470 PetaJoules of energy. So the energy gain from Rossing is close to a factor of 500. The grade of Uranium at Rossing is 0.035% by weight (about 350 ppm). Deffeyes & MacGregor have estimated the distribution of Uranium in different types of rock and show that shales and phosphates contain 8000 times as much Uranium as current Uranium Ore bodies at a concentration of 10 -20 PPM. These rocks are potentially minable with an energy gain of 15-30.
Consequently, unlike conventional Oil, Uranium resource exhaustion will not be an issue for the foreseeable future.
Energy Lifecycle of Nuclear Power
The performance of Nuclear Power can be compared to other energy sources by calculating the total energy required to build and run a Nuclear Power plant and comparing it to the total energy it produces. The following set of calculations is also taken from the independently audited, Vattenfall Environmental Product Declaration for its 3090 MW Forsmark nuclear power plant in Sweden. A more detailed description is here. Vattenfall have also made available the aggregated data set as a spreadsheet. You can download it from here. Vattenfall is a large European Energy utility that operates a variety of energy generation technologies including Nuclear, Hydro, Natural gas, Coal, Oil, Peat, Biomass, Wind and Photovoltaic. We chose this because it had been independently audited, and includes the entire lifecycle of the processes which includes the eventual long-term disposal of the waste. Sweden and Finland have perhaps the most developed nuclear waste disposal plans of any country.
The following table displays the source and the amount of energy required to produce 1 KW-Hr of electricity. The table includes the energy used in construction of the plant, mining the Uranium, enriching it, converting it to fuel, disposing the waste and decommissioning the plant. The plant is assumed to run for 40 years. There is an additional 0.026 grams of Uranium consumed in generating this one KW-Hr of electricity. This 0.026 grams includes the Uranium used to generate power and the Uranium consumed by the French Nuclear Power plants that produced the electricity that enriched the Fuel.
So the Plant produces 93 times more energy than it consumes. Or put another way, the non-nuclear energy investment required to generate electricity for 40 years is repaid in 5 months. Normalized to 1 GigaWatt electrical capacity, the energy required to construct and decommission the plant, which amounts to 4 Peta-Joules (PJ), is repaid in 1.5 months. The energy required to dispose of the waste is also 4 PJ and repaid in 1.5 months. In total this is less than 0.8% of the all the electrical energy produced by the plant.
Greenhouse Gas emissions
Although the processes of running a Nuclear Power plant generates no CO2, some CO2 emissions arise from the construction of the plant, the mining of the Uranium, the enrichment of the Uranium, its conversion into Nuclear Fuel, its final disposal and the final plant decommissioning. The amount of CO2 generated by these secondary processes primarily depends on the method used to enrich the Uranium (the gaseous diffusion enrichment process uses about 50 times more electricity than the gaseous centrifuge method) and the source of electricity used for the enrichment process. It has been the subject of some controversy. To estimate the total CO2 emissions from Nuclear Power we also use the work of Vattenfall.
Vattenfall finds that averaged over the entire lifecycle of their Nuclear Plant including Uranium mining, milling, enrichment, plant construction, operating, decommissioning and waste disposal, the total CO2 emitted per KW-Hr of electricity produced is 3.3 grams per KW-Hr of produced power. Vattenfall measures its CO2 output from Natural Gas to be 400 grams per KW-Hr and from coal to be 700 grams per KW-Hr. Thus nuclear power generated by Vattenfall, emits less than one hundredth the CO2 of Fossil-Fuel based generation.
Nuclear Costs
The cost of generating power via nuclear energy can be separated into the following components:
- The construction cost of building the plant.
- The operating cost of running the plant and generating energy.
- The cost of waste disposal from the plant.
- The cost of decommissioning the plant
Quantifying some of these costs is difficult as it requires an extrapolation into the future.
Construction Costs
Construction costs are very difficult to quantify but dominate the cost of Nuclear Power. The main difficulty is that third generation power plants currently proposed are claimed to be both substantially cheaper and faster to construct than the second generation power plants now in operation throughout the world. The Nuclear Industry says its learned the lessons of economy-of-volume demonstrated by the French Nuclear Program, and that these will be employed for the new power plants. For example Westinghouse claims its Advanced PWR reactor, the AP1000, will cost USD $1500-$1800 per KW for the first reactor and may fall to USD $1200 per KW for subsequent reactors. They also claim these will be ready for electricity production 3 years after first pouring concrete. This should be compared to second generation plants which, in the U.S.A., had construction costs up to $6000 per KW and generally took more than five years to complete.
Meanwhile the Chinese Nuclear Power Industry has won contracts to build new plants of their own design at capital cost reported to be $1500 per KW and $1300 per KW at sites in South-East and North-East China.
Operating, Waste Disposal and Decommissioning Costs
Operating costs are much easier to quantify and are independently verified as they relate directly to the profitability of the Utilities which operate them.
Since 1987 the cost of producing electricity from has decreased from 3.63 cents per KW-Hr to 1.68 cents per KW-Hour in 2004 and plant availability has increased from 67% to over 90%. The operating cost includes a charge of 0.15 cents per KW-Hr to fund the disposal of radioactive waste and for decommissioning the reactor. This fund is currently capitalized at $24 billion dollars. The Swedish Nuclear Industry has charged 0.5 cents per KW-Hr for waste disposal and decommissioning. Sweden has well developed plans for these which appear to be adequately covered by these charges. The US plans for waste disposal at Yucca Mountain remain highly controversial. It may be that the charges levied by the US NRC are insufficient.
Sensitivity Analysis of the cost of Nuclear Power
In our study we performed a sensitivity analysis of the cost of Nuclear Power. We employed a simple model which gives a reasonable guideline to the cost in US cents of electricity per KW-Hr based on various assumptions for construction cost, operating costs, interest rates and construction time. The plant is assumed to have a 1 GW capacity.
If we assume a 7% interest rate and 4 year construction period, US operating costs in the second best quartile, the cost of electricity production for plants that cost $1.2 Billion, $1.5 Billion and$ 2.0 Billion US dollars would be 3.3, 3.8 and 4.4 US cents per KW-Hr respectively. If the AP1000 lives up to its promises of $1200 per KW construction cost and 3 year construction time, it will provide electricity fully cost competitive with Fossil Fuel based generating facilities.
Safety of Nuclear reactors
The chain reaction that provides the power-source of nuclear reactors, is controlled by adjusting the neutron multiplication factor, k. The parameter k is the overall fraction of neutrons from one fission generation that initiate further fission reactions. If k > 1 the number of neutrons grows with time and more power is generated. If k < 1, the reaction decays with time and less power is generated. In a steady operation k is adjusted to be almost precisely 1. This is possible because round 1% of the neutrons in a reactor are emitted after a delay of a several seconds even though the typical cycle time between succeeding generations in a light water reactor is of the order of 10 milliseconds (these are initiated by prompt neutrons neutrons directly from the fission). The multiplication factor is adjusted by changing the configuration of control rods which absorb neutrons within the reactor.
In addition to this active control two natural processes provide negative feedbacks which stablize the reactor. The first of these is a negative temperature coefficient. As the temperature of the fuel increases, the vibrational energy of the 238U increases which increases the rate of neutron absorption. Thus k decreases and the reaction rate slows down. The second is what is called a "negative void coefficient". What this means is that if the water that is used to cool and moderate the neutrons decreases in mass (for example via steam bubbles forming voids), it no longer is an effective neutron moderator which also slows down the reaction rate.
So light water reactors are inherently stable to first order. Of course things can and do go wrong over the course of time. These are normally corrected by routine adjustments of the reactor parameters. However the worst thing that can happen is for a massive loss of core coolant via a catastrophic accident. If this happens the nuclear reaction will stop but the fuel itself will continue to generate heat from the radioactive decay of fission products. Without the cooling water, the fuel elements will eventually melt. Should this occur, the fuel is contained within the extremely strong shell of the containment vessel. The melt-down will destroy the economic value of the reactor, however the public remains protected. To prevent meltdowns, current second generation reactors employ multiple backup cooling circuits driven by active components like pumps and valves. These are active safety systems and modern reactors are projected to have 1 major core damage incident per 100,000 years of reactor operation.
In contrast, new designs such as the Westinghouse AP1000 employ principles of physics such such as phase change and gravity to maintain cooling water in the event of a catastrophic loss. The design is simpler, smaller and safer and cheaper than current reactors. The American NRC estimates 1 major core damage incident per 2 million years of reactor operation for the AP1000.
There are been numerous reactor incidents over the years. Some more serious than others and most recently at the Forsmark complex cited above. However Three Mile Island and the Chernobyl catastrophe are the events that most people associate with Nuclear Power accidents. The Three Mile Island accident resulted in a contained melt-down. The Chernobyl event was the result of a fundamentally unsafe reactor design (the graphite-moderated, water cooled reactor has a positive void coefficient at low power as well as no containment vessel) together with a complete lack of safety culture. The following links provide excellent descriptions of the Three Mile Island and Chernobyl events.
The Three Mile Island accident caused the US NRC to re-evaluate Nuclear Plant designs and in many cases ordered changes. These changes were both expensive and time consuming to fix but have increased the safety of US plants.
It is a condition of entry to the EU that Chernobyl style plants be shutdown.
Nuclear Waste
Spent Nuclear Fuel (SNF) from a reactor is highly radioactive. The activity can be broadly divided into two classes. Fission products, (nuclei created from the fission process) and Trans-Uranics. These are nuclei that are heavier than Uranium and are created when 238U captures a neutron. Fission products are generally short lived while TransUranics can have half-lives in the range of tens of thousands of years.
Once the SNF has been removed from the nuclear reactor it is placed in interim storage at the reactor site. Usually this consists of putting the nuclear waste into large pools of water. The water cools the radioactive isotopes and shields the environment from the radiation. Nuclear waste is typically stored in these supervised pools between 20-40 years, although this could be reduced to 5 years. As the SNF ages the radioactivity decreases, reaching the point where can be placed in dry storage facilities. Throughout this time there is a great reduction in heat and radioactivity and this makes handling of nuclear waste safer and easier. However the TransUranic component of SNF must still be isolated from the environment for 100,000 years or more. The fission products typically reach background levels after 500 years.
After this "cooling off" period the high level waste can be handled in different ways. It can be reprocessed (which invloves extracting the Uranium and Plutonium) then disposed of permanently or directly disposed permanently in a geological repository. There is also very active research into "burning" the TransUranic's in either advanced reactors or accelerator driven subcritical assemblies. However this technology has not yet been developed to work on a large scale. Finally it could be left in dry casks for "interim storage". These are predicted to be safe and stable for at least 1 century.
The most advanced concepts of long-term disposal of Nuclear waste is for deep geological burial. The Nordic countries, Sweden and Finland are perusing solutions which employ multiple barriers to provide isolation from slow-moving groundwater. Finland has selected a site for disposal, Sweden is choosing between two locations for their facility. The earliest start up date for the repositories is 2017.
Nuclear Proliferation
The Uranium enrichment used for light water reactors is not sufficient for a Nuclear Weapon and while light water reactors produces hundreds of kilograms of plutonium during operations, the plutonium produced has too much 240Pu for a useful Nuclear Weapon. What happens is that the 240Pu builds up in a reactor with operation. In a light-water reactor, the 240Pu exceeds useful concentration (7%) after 4 months of operation. Nuclear fuel is normally left in place for over two years. After this time the 240Pu concentration is 25% which is well beyond the militarily useful range.
For this reason, light water reactors are called proliferation resistant. Normal operations preclude the production of militarily useful Plutonium. Abnormal operations are easy to detect.
Conclusions
Technically, there appear to be no show stoppers for a considerable expansion of Nuclear Power throughout the world. It is a low carbon energy source with abundant fuel supplies. The technology works and has much potential for improvement. Whether or not a large scale expansion eventuates depends on how it competes with Coal on economic grounds and with the public on political grounds. This in turn will be determined by the performance of the nuclear industry over the next few years as these purportedly cheaper and safer plants are built.
I think it is worth showing the final graph from M. King Hubberts' seminal paper "Nuclear Energy and the Fossil Fuels".
Until this question is answered I dismiss nuclear power as viable.
If you mean to ask the question, "how do we dismantle nuclear power plants with fossil fuels that will be increasing in expense and decreasing in availability over time?" (we're not going to be without fossil fuel for a while, or don't you read the site much?)...well, I think that's a much more apt question.
I read this site much, and clearly understand we won't be running out of FF anytime soon, or ever, maybe. I did read the piece and am open to a discussion on nuclear power. I apologise if my comment suggests otherwise.
However:
By no means it is clear that what are now the major population centers that at present consume a lot of energy and which are the locations for future nuclear power plants, will have access to any FF in 60 years time.
Despite suggestions that we will have the equipment for mining , processing and transporting minerals for nuclear power plants, and the equipment to decommission these, all running on electricity, this underlying infrastructure is nowhere in place as far as I can tell. This will require a complete redesign, replacement, and extension of all present machinery used for these processes. Keep in mind that if we intend to get a good part of our electricity from nuclear power, we need to build many more stations then we have now.
I have also trouble with the costs that are mentioned. First, estimating now the costs of building a plant that will take several years to have completed is guaranteed to overrun the proposed budget.
Second, calculating 15 cts. per KwH for decommission costs 60 years from now is based on todays' economics and thus hard for me to see how it can apply to a situation so far ahead (though obviously something should be calculated).
Third, in calculating the costs for a nuclear power plant it is asumed the underlying infrastructure, i.e. the electrical grid to transmit the generated electricity, is in place. It is now, but it's old and vulnerable already. I think the grid needs some serious upgrading if men is to switch to more electric power (be it nuclear or otherwise) and less FF. All in all the economics seem a bit doubtfull.
Finally, the waste. There probably are ways to deal with this. Clearly stuff with a half life of thousands of years should be put away properly, and not like here in Holland at http://www.covra-nv.nl , which is at sealevel. Despite all the protective measures eventually these will wear out.
Nuclear power will probably stay part of an energymix if we intend to peacefully and gradually powerdown, but it has no future in the long run, and frankly, I feel it is a bit like playing God.
Use hydro, wind or solar generated power to melt down steel & other metal into metal that is not exposed to people (concrete rebar comes to mind). Use air jack-hammers to break-up concrete and use for roadbeds or other "scrap concrete" use.
IMHO, "once through" fuel rods will be retrieved from storage after a century or two and refined/reprocessed for their platinum group metals (plus gold, silver, germanium, etc.).
The degree of employee health safety measures might be excellent in 2138, or they may not be.
What to do with the zirconium though ? (Nuke fuel rods are often built of zirconium from memory).
Simple enough for you?
um, using electricity? How about producing hydrogen with the nuclear power and then making methanol from that?
This is the most tired argument around... "The CEO's limo runs on gas, therefore without gas the CEO can't show up to work, therefore nuclear power isn't viable without gas...."
The solutions are entirely obvious. Only willful ignorance would make it otherwise.
The reality of the matter though is whether you want the reactor in your back yard, or someone else's... Thats where the issue arises.
PTB = Powers That Be
TLA = Three-Letter Acronym
OTOH, IMHO, PTB -> BTL.
Other problems with nuclear:
-the possibility of a meltdown and the NIMBY syndrome
-the superheated water coming out of a plant tends to kill wildlife and acquatic ecosystems. (This applies where steam is circulated back into the water source, instead of being let out the vents.)
-contrary to popular belief, even disregarding the nuclear waste, they are not 'green' energy, as they spread some radioactivity in the surrounding environment.
-it takes about ten years to build and approve one nuclear reactor, which is dependent on fossil fuel use. Do we have that much time?
I have also seen two studies (don't have the links, sorry) that suggested we could make enough nuclear reactor power stations to supply all the world's energy -for about a year. That's how long the fuel for that many reactors would last.
Finally, nuclear is only good for generating electricity, which accounts for about 30% of our power use. Where does the remaining 70% come in?
Well some of us have a fallback to the "silver bb" position, which is that maybe there isn't one big technology to save us, but enough samll things to add up.
On that front, I wouldn't be sure that nuclear requires fossil fuels. In a world with many small energy sources, nuclear might be important enough to pull energy from somewhere else. I mean, if you've got some biodiesel, using it to build a nuke plant might be one of the better ways to leverage that fuel.
The best propaganda is.
Here's a pointer towards the existance of someone who thinks there are some issues with the Gandhi PR.
http://www.tv.com/penn-and-teller-bullshit!/holier-than-thou/episode/415462/summary.html
Things can change -- often for the better.
Yet many times they change for the worse. The dead tend to stop complaining however.
The best propaganda is.
Here's a pointer towards the existance of someone who thinks there are some issues with the Gandhi PR.
http://www.tv.com/penn-and-teller-bullshit!/holier-than-thou/episode/415462/summary.html
</yawn>
ooooh, Ghandhi wasn't a saint. Who would have thought!? Did you know Martin Luther King slept around and Thomas Jefferson had slaves too? That they are imperfect doesn't take away from their accomplishments and importance to history.
I think I'll base my opinion on Ghandhi on more than what a couple of two-bit magicians say.
Like a movie ment to entertain?
So when Prodigal Son says "things get better" and cites an example where "things got better" by a certain group of people getting more energy then they had previously, that is not really applicable to our situation as there ain't going to be more energy to gotten fore anybody unles you mean steal it from whoever has it.
Sonny Boy also believes there is nothign wrong with the federal reserve.
In the same way he tries to handwave away questions as a couple of sleight-of-hand artists opinions (my far more insulting dismissal of their comments BTW), he also hand ways away questions 'bout the Federal Reserve as 'conspiracy theories'.
I'm waiting to see how the Gandhi belief of 'passive resistance' will be applied to the US Dollar when no one wants to exchange it for oil. (You know, applying the valuable lessons from the movie) Then I can have my own Schadenfreude about how useful and correct the Federal Reserve is. I'll be to busy not having any oil-based products, but one has to take what little joy they can get in an oil-less system.
Also boiling that conflict down to just being about "energy" is really just absurd.
All of those problems, though true, are literally insignificant next to problems of Peak Oil and global climate change.
As fossil fuels get more expensive, then people's use of electricity to replace fossil fuel use will increase.
Also, "total energy" may be counted in a potentially improper fashion.
For instance, if you count, e.g. megajoules of heat in petroleum, and then compare to megajoules of electricity as delivered to customer that is handicapping electricity.
Because of thermodynamics, the combustion of petroleum in various forms only provides a moderate fraction of total heat energy as work, whereas nearly all of electrical energy can go to work.
More fair (but still rough) would be to compare total BTUs available in petroleum to the total heat inputs provided by the nuclear reactors (or other electricity generating sources) into the generating turbines.
In short: compare heat to heat, or work to work.
Why? Nuclear energy IS dependant on energy to build, maintain, dismantle the plant, but why does that energy need to come from a fossil fuel? It doesn't. It will come from nuclear energy, because electricity from nuclear will replace fossil fuels as the baseline energy source.
"Finally, nuclear is only good for generating electricity, which accounts for about 30% of our power use. Where does the remaining 70% come in?"
The remaining 70% will need to transition to electricity. Electric cars replace internal combustion cars, electric cooktops replace gas cooktops. OK, maybe 65%. The other 5% that cannot use electricity (airplanes for example) can use synthetic fuels produced with energy from electricity.
you created a feedback loop that kills your argument.
to move say the entire car infrastructure to electric would cascade increased requirements throughout the system, furthermore to ask that the energy requirements for the tools to build these systems to be run on electricity as well does the exact same thing. to build you need electricity, to get electricity you need to build. the current system will not support the current 30% usage today AND the increased load of you moving the other 60% over to electricity, while at the same time accounting for growth.
i also know your going to say
but thats exactly whats happening now with oil so your wrong
this is not true because oil is a energy source and electricity is a energy Carrier
as to the article this is article like it or not goes into much more depth.
http://www.stormsmith.nl/
this is a very nice record of so called safety.
http://www.lutins.org/nukes.html
please keep in mind nuclear energy is just a very complex way of boiling water to produce steam to turn a turbine which makes electricity. it was and always has been a secondary use of reactors, primary being nuclear weapon material production or depleted uranium(dirty bomb) material production.
i already know i have been labeled a troll for not having a pair of rose colored glasses(shouldn't you have turned those in at the desk before entering the realm of peak oil?).
Build more/larger nuke plants!!
That's right, back in 1906, who would have concieved a ship made to haul 50,000,000 gallons of oil?
The nearest nuclear facility to me currently has 3 reactors, and is begining construction on a fourth. It can currently produce about 3 gigawatts. Interestingly, when the site was built over 20 years ago, it was designed to have the capacity for up to 16 reactors....
Also, reguarding your comments on electricity being an energy transmission medium and not a storage medium... Well, technically you can't draw those boundries... One could write a very long essay debunking such notions, but let me summarize it with one simple equation: E=m*c^2
That's right, that sunlight on your arm is the same thing as the electricity in the powerlines, and the gas in your tank... in fact as the keyboard under your fingers. If you want to really warp your mind, think that traveling at speed causes mass...
I don't expect you to have rose colored glasses, but I damn well am not giving up my indoor plumbing to save an endangered tree frog.
The nameplate generating capacity of the US grid is over 970 GW; the average demand is less than half that, at ~450 GW. The "cascade" goes as far as additional fuel required for existing generators, and comes to a screeching halt there. Since electric generators can be far more efficient than vehicles, this additional fuel could be obtained by diverting oil in the short term.
The bulk of the system is already built to handle peak loads, which are ~2x the average load and 2.5-3x the minimum. The generators are already built. One big change that would be desirable would be to convert from simple-cycle gas turbines at ~40% efficiency to combined-cycle turbines at ~55%; this change would be enabled by the flatter demand curve created by off-peak charging, and cut the overall fuel requirements substantially.We could easily find 70% just through efficiency gains and through modification of lifestyle. However, what I expect you're saying is where does the transportation fuel come from. Ultimately peak oil is a liquid fuels crisis. To consider nuclear as a replacement for oil you would have to add the step where you convert the electricity into a liquid fuel equivalent, (eg. hydrogen).
As Switzerland showed during WW II, one can operate a decent democratic society with electric railroads, urban rail, trolley buses, bicycles and shoe leather. Current technology would allow limited range EVs as well. The only truly essential need I see for liquid fuels may be ambulances outside urban areas. (Very limited police use as well, if one discounts military needs. Farming with bio-gas & electricity will be difficult in many areas, and liquid fuels may be a better option). Air travel is EXTREMELY "nice" but not required for civilization.
Yes, it is "different" and will require changes, but it *IS* doable !!
Nuclear makes electricity, true. The US uses about 100 quads of energy per year, perhaps 40 quads of it from oil. Some decent batteries would allow the replacement roughly 80% of gasoline (~18 quads) with electricity. That's 14-15 quads, and you're up to 45%. Diesel for trucks? Electrify the trucks or move to electric trains; you're past 50% (and over half of petroleum). Space heating? Electric heat pumps replace gas furnaces.
While I would never suggest nuclear as a panacea, it's completely wrong to suggest that it cannot replace lots of other energy supplies.
A bit over 20 years ago I sat through the environmental hearings for expansion of an existing nuclear power station. I had to be there throughout the whole proceedings, with my principle learning point being this:
The anti-nuclear lobbyists came to the hearings with their minds already made up. No fact, no information presented was going to change their beliefs. They left the hearings, which they too sat through, about as ill-informed as when they arrived. Such a shame.
As an old anti-nuke guy, I understand what you are saying. Working in solar in the 1970's and seeing huge stipends from the govt. going to nuclear was very frustrating. But I do not think we were not listening. It was obscene, and still is to some extent, to think that we would create nuclear waste that would last longer than the history of civilization. It is and was a blasphemy before God.
As to ill-informed, we did have 3 mile island. To error is to be human.
Now, because of the mess we are in, I will grant that nuclear can be a bridge to the future. But it is not a lasting solution given today's technology, as if we should have mini-suns in every state of the Union. Renewables and solar are the ultimate solutions, but we need the bridge for now.
Thousands of people a year are dying and many more are being crippled by the toxic waste generated today and this legacy will endure. Why is the very small possibility of a leakage from underground disposal of nuclear waste some long time in the future that might, or might not, make a relatively small area of the planet risky to live in so much more obscene than rape and poisoning of so much of the planet that that our present energy system involves and the even worse rape that will stem from the alternatives being promoted such as tar sands, oil shale, sulphur and vanadium contaminated very heavy oil and the massive expansion of coal extraction.
It will doubtless bring wrath on my head to say it but in the end radiation poisoning is just another way to die and although a horrible way to go not the worst. If it was a pure choice between incurring a small risk of such deaths and not doing so we should avoid it. It is not however not a pure choice. We have to do something about our energy use. Inaction will lead to mass starvation and all the alternatives carry great risks including promoting resource wars.
What does it take to get people to rationally access the risks and benefits of the various options?
In terms of damage to biological tissue, probably it isn't so hard to get a common scale. We might use some measure like average years of life lost per gram of toxin ingested. These numbers are probably around someplace. One of my colleagues had a nuclear engineering textbook with some numbers along these lines - plutonium dust outranked all the other radioactive toxins by orders of magnitude, but the charts just had radioactive toxins - no comparison with e.g. lead dust.
Any kind of chemical toxin is obviously active chemically. So an interesting possibility is that a chemical toxin could be made a lot safer by compounding it with some other chemicals that bind to it more tightly than biological materials would. In general, it seems like a chemical toxin has this possibility to be deactivated chemically. Whereas we really don't have a way to neutralize the radioactivity of plutonium. If it gets into your body, that's bad news.
I would love to see any kind of encyclopedia of toxins to understand the various chemical and mechanical pathways into the body. Perhaps there is some way to chemically compound plutonium in a very stable way so it just can't cross into biological tissue. But I don't think anybody knows any such way.
Another monster problem with radioactive toxins like plutonium - the radioactivity damages any kind of containing vessel. So you might have a tightly sealed leak-proof vessel one day, then a few hundred years later the steel is all pitted and corroded and starting to leak. Again, there is no way to chemically or electrically treat the radioactive waste to prevent this kind of damage.
So you're right, to make any kind of rational decisions, we need to be able to put plutonium and arsenic on some kind of common scale, to be able to weigh them and compare them. The problem seems to be that plutonium really is very dangerous. Not that it kills people any deader than arsenic, but that it is a lot harder to stop it from killing people than it is to stop arsenic.
That's true. But what you can do is to use actinide burners, nuclear reactions and reactors to transmute the long lived transuranic elements to ones which decay in hundred-year timescales.
Over this timescale, you can easily overbuild the container to be very safe, given that the amount of nuclear waste is very small for the amount of energy (and hence economic value) which it produced.
Remember, the best is the enemy of the good.
We have people dying, today, from coal mining and coal-caused pollution. We will have people dying by the thousands to millions from the accelerated global warming from the burnup of coal and tar sands.
Not that it kills people any deader than arsenic, but that it is a lot harder to stop it from killing people than it is to stop arsenic.
This isn't really true: plutonium on its own is not that radioactive.
Either way, arsenic dust or plutonium dust is very bad news. The solution is to keep it solid, and in a box, and don't eat it.
Arsenic goes into some processes of making high speed microchips----in the factories and research labs they even use gases with arsenic.
Just in the next building over from me (I am at a research university) there is a semiconductor fabrication laboratory which uses phosgene and arsenic all the time.
Can you imagine the approvals necessary to get a plutonium laboratory in an academic engineering lab? And yet that level of danger is well accepted for semiconductors.
Good insight. I had never thought about it quite that way.
But I work in a business where we do re-mediation from time to time and I'd rather do the Lead than Nuke Waste. And when we dumped a load of mercury in a river, it would sort itself out in a hundred years (if not added to).
Nuke Waste is different.
Dont despair, I have been anti-nuclear.
A nuclear power complex which includes reactors, generators and ancillary equipment ought to be maintainable, with significant sustained maintenance effort, for a very long time.
It ought to be designed so that components inside of them can be refurbished and replaced. Eventually that may include reactors as, I hope, new designs which are safer and produce less long-term waste (actinide burners/accelerator based) are invented.
If we find ourselves unable to replace nuclear reactors because of a total lack of liquid fuels then we will have enormously greater (civilization-ending) problems, like not being able to build a building more complex than a dirt burrow.
I envision high energy input (e.g. from nuclear or wind or non-fossil sources) production of biofuels as possible in the long run. At some basic level we ought to be able to take the heat or electricity from nuclear power and infuse it into useful chemical form. This is not going to be necesessary for about 150-200 years.
Given the amount of coal and feasibility of coal-to-liquids (which is going to be inevitable in the short run, given petroleum depletion), I favor rapid expansion of nuclear and wind power to replace coal-based electricity generating and satisfy new electrification demand. The alternative is climate catastrophe with coal-to-liquids.
If we find ourselves unable to replace nuclear reactors because of a total lack of liquid fuels then we will have enormously greater (civilization-ending) problems, like not being able to build a building more complex than a dirt burrow.
"
This is the end result I personally hope for. While the Amish seem to do a bit better than dirt burrows, let's count them out for the moment and consider this. People in our civ. work their whole life, run their life away on the treadmill, to own, maybe, if they're lucky, a house. Pre-civ people build one. Illness, marriage break-up, etc or simply a mis-filing of papers, is disastrous for the "happy homeowner" (more like happy home-owned) in our civ. Pre-civ people just build another one. There was a Navaho guy on this radio show I was listening to one ranting about this, and it was hilarious. You break up with da wife, she gets the hogan - you go build yourself your own one. "And no halfers" as he put it, she got the "stuff" you had too. No problem since "stuff" is easy to get and make again. Bunch of other stuff, essentially pointing out how fucked-up our civ. is and how much richer those poor-ass Navajos really are in a lot of ways.
People have experimented with everything from teepees to the kind of half-dug-in round houses the ancient people in England lived in and the old house types seem to work pretty well. Especially when you don't have gobs of petro-energy flowing in. The only people I've ever heard of actually living in a dirt hole in the ground was in one of the Little House On The Prairie books, they lived in a "dugout" in the side of a dirt hill, until they could build something more Civilized and draftier.
Let's see.... who else lived in a hole in the ground? Oh yeah, the Unibomber's brother, the guy who turned him in. You see, Uni's younger brother was also interested in self-sufficiency, and went out and lived in what was described as "essentially a hole in the ground" for a few years with his Mexican wife. He did that for a while, then returned to mainsteam society, and worked or works, with disadvantaged kids. Apparently as warm and human as Uni is a cold, schizo, freak. Uni on the other hand lived in a plywood shed, just about the worst type of building I can imagine for that land and climate, and contrary to his self-sufficient beliefs, didn't seem to do that well on the land. He really should have ended up fat, dumb, and happy if he's paid more attention to his hunting and gathering. Instead, that took back seat to reading scientific books and probably muttering at them, and building his bombs. But at least he didn't live in no hole in the ground!
The advantage of designing and building them yourself is that things are done right with no cheapo shortcuts and they all included energy efficiency as part of the design process. Our current one, that I built about 25 years ago, still grossly exceeds mandated energy efficincy codes.
And FWIW, I had zero significant building experience other than being involved with chemical plant construction as the start-up manager.
Todd
As I recall, the complex at Yucca Mountain is to be designed to remain stable and safe for 25,000 years. That sounds like a long time, until one realizes that glaciers last covered the area roughly 25,000 years ago.
In addition to fuel waste, I wonder if the Australians have adequately looked at raw material production and waste. Canada, one of the largest producers of Uranium, has plenty of U-related environmental disaster zones. Increased exploration, particularly in regions with lax environmental regulation (as with gold or oil or any material from the earth) will result in more environmental harm.
Personally until I hear more talk about conservation than about "alternatives", I won't buy into any replacement for carbon.
The logistical problems of transitioning away from the collapse of petroleum will mean that there isn't enough time. We have to start on everything, now, that isn't climate death: wind, conservation and nukes.
Electrification of transportation will create major new demand, so even with strong domestic conservation {which I favor 100%} we will need significantly more electrical capacity. I don't want it to be coal.
Of course there are local environmental screwups from mining---but without nuclear it will be coal in real reality for baseline power---and that's much worse.
Consider: what is the volume of coal waste (fly ash) versus nuclear waste? What is the volume of coal mining versus uranium mining? What is the half-life of the heavy metals in the mountains of coal ash being produced? (Infinite) What will happen to them in 25,000 years? They will still be toxic.
Are these mountains of coal ash going to be expensively buried in a single highly-monitored location? (no, they're dumped on the ground, outside, and they pile up.)
Re nuclear waste: we need really worry about 200 years, not 25,000 as that's the time it is particularly dangerous.
Further actinide burner cycles in reactors, though not in production now, can burn up that high-half-life nuclear waste and result in waste which decays much faster, therefore obviating the need to make predictions in geological time. So we need now make waste repositories which are decently secure, and from which we can retrieve the cans to fix them.
Common sense suggests there is something wrong with that as a long term (decades, centuries) scenario.
So? Think more. Holler at each other a lot less.
I think what you intended to say is that software, music, and literature, constantly evolve.
You can deny that Beethoven was a greater composer than Britney Spears, but most folks will consider that to be silly. (OK, OK, for all I know B.S. doesn't call herself a composer, fill in the blank however you please.)
I agree. IMO, we should replace the payroll tax with a tax on energy consumption, especially at the pump, combined with a crash electrification of transportation program and a crash wind/nuclear program.
From nuclear + fossil fuel sources, we use the energy equivalent of one Gb of oil every five days.
We use the energy equivalent of the Prudhoe Bay Field every two months.
We use the energy equivalent of all of ExxonMobil's proven oil and gas reserves in less than four months.
This is why I think that our best hope is to slow the rate of decline of total energy production--until at some point things stabilize. I can't see how we can grow the energy supply.
Why not with wind and solar (not to mention wave and biomass)?
The US has about 2 terawatts of wind potential, which is enough to replace all of our coal generation AND power all the light rail and EV's that we might want. Wind has an E-ROI of 35:1 to 65:1. Planned wind generation is 30% of overall new generation in 2006 and 40% in 2007 (adjusted for capacity factor (these numbers are a bit lower than my previous numbers, based on a higher capacity factor for NG)), and this trend is likely to continue. Wind could easily handle all new generation in the US within 5-10 years.
Wind at about 5% per kwhr is already cheaper then nat gas, and is pretty close to coal (cheaper if you include even a portion of external costs like pollution, GW, occupational health, etc). Wind will be very easy to expand, as there are a lot of farmers just dying to get a wind farm or expand the one they already have, and manufacturing of wind turbines is a pretty straightforward thing to expand. Not overnight, which is why wind developers are currently limited by the turbines they can lay their hands on, but pretty straightforward.
Solar? The earth receives 100,000 terawatts continously from the sun, and humans use the equivalent of 4.5 terawatts on average.
Solar costs are now around $.25/kwhr. Given that solar competes with retail electric rates, this is actually competitive without subsidies in some places: So Cal and Japan in particular (though subsidies are growing in So Cal, and phasing out in Japan). Solar costs are dropping about 10% per year, which puts it at $.125/kwrh in 10 years, and $.06 in 20 (this is a cost-reduction path which is reasonably well accepted among experts in the area - actually, it may be much faster, with things like Nanosolar happening).
Biomass can provide all the chemical feedstock we need.
So, in the long run there's plenty of energy. It's just the transition...
I agree that at some point the total energy supply will stabilize, and perhaps start growing again. The problem is getting from here to there.
Our non-renewable energy use of the equivalent of one Gb of oil every five days is an incredible amount of energy.
If we found an entire new Saudi Arabia, it would increase our nuclear + fossil fuel energy production rate by less than 5%.
Bad to swallow you whole
Kick the clay that holds the teeth in
Throw your trolls out the door
If you're needing inspiration
Philomath is where I go by dawn
Lawyer Jeff he knows the lowdown
He's mighty bad to visit home
I've been there I know the way
(Can't get there from here)
-REM, "Can't Get There from Here," Fables of the Reconstruction (1985)
Besides, you don't have to grow the supply if you can just improve the efficiency (grow product with the same supply). Direct-carbon fuel cells are my favorite example of that. Current cellulose-ethanol schemes are about 48% efficient, feeding vehicles which are about 15% efficient for field-to-wheels efficiency of 7.2% at best. Charcoal production is also ~50% efficient (not including heat and chemical energy in the off-gas), but DCFC's are 80% efficient for ~40% field-to-wheels. That's more than 5 times as good.
I've run the numbers and found that we could replace roughly half of gasoline with ethanol from our 1.3 billion tons/year of cellulose, or more than the USA's entire net energy consumption from motor fuel using charcoal from that cellulose and burning it in DCFC's. Would you consider that growth, or shrinkage? I call it improvement!
Nuclear breeders are where it's at - thousands of years of supply of U238 sitting around - right now we have so much of it that's been depleted to make U235 we're making bullets out of it(as a conveniant heavy metal).
It's 2006, and we've yet to breed even a reasonable fraction of a single fuel load in all the breeders ever built.
I understand your optimism, but it's kind of like basing civilization on something as expensive, complex and fragile as the space shuttle.
Lately I've been thinking most folks don't want to believe that SUVs are on the table when Peak Oil hits, but even the table is on the table when Peak Oil hits.
Even LWR's breed a substantial amount of fuel (just not as much as they burn). I found two references to the Shippingport reactor's test on thorium in which it yielded a breeding ratio of 1.01.
No, if we had one of those we wouldn't need to be messing about with reactors at all, would we. ^_^ I'll have to think about what I'd actually do with that wand to solve the energy problem. My first impulse was not to populate the world with breeder reactors, but that's my bias.
My point was specifically about the output of comercial fast breeder reactors, which have had a less than stellar operational history. I'd love to see figures that show
the actual net fuel gain of those plants. (Anyone?)
Yours is interesting point however. Clearly some of that plutonium came from reactors specifically tasked to producing it, and some from re-processing spent fuel rods. T