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Sounds like a slippery slope. From a selfish UK perspective, how long will it be before we have a government controlled 'Internet standards authority' that 'requires' ISPs to block or slow access to any sites that do not promote Marxist values? If the practice of neutrality is dropped in the US, this sort of censorship would occur quite rapidly in the UK, because it is not a constitutional democracy in the way that the US is. There are all sorts of oppressive laws controlling what an individual can say and do that would be unimaginable to people living in the USA. These people would like nothing more than to control internet content.
Maybe it's time to get a VPN?
My understanding of plasma physics is limited, but there is one thing I have never understood. The Lawson parameter for self-sustaining fusion within plasma is the product of particle energy, particle density and average confinement time. When the product exceeds a critical value, fusion becomes self-sustaining. Energy determines particle speed; density is a function of temperature and pressure; simplistically (assuming no collisions between ions) average confinement time is average speed divided by vessel diameter.
One simple way of increasing particle confinement time would be increasing the size of the reactor vessel, as at any given speed it will take an ion a greater period of time to cross the vessel and reach the adjoining wall if the vessel is larger. A spherical vessel of sufficient size filled with plasma should therefore have no difficulty reaching ignition, it is only a question of minimum vessel size and plasma density. The vessel walls can be protected from erosion by injecting a boundary layer of cold gaseous fuel through pores in the vessel walls. This would negate the need for a magnetic field. Within a large enough plasma, the majority of particles will tend to collide with each other and only those close to the outer edge would have a high probability of colliding with a cold gas particle. On this basis, a temperature gradient would develop within the plasma and fusion reaction rates would be much greater towards the centre. Neutron collision with the cooler outer gas particles would tend to flatten the temperature profile of the reactor somewhat, but the edges would be cold and would gradually diffuse into the centre. Power could be extracted by bleeding hot plasma from the outer edges of the plasma through a magnetic nozzle into an MHD generator. This would also remove waste helium ions.
Presumably, there is an underlying reason why such a simple device has not been built. Maybe the minimum size or plasma pressure for this arrangement are too large to be practicable? Maybe there are plasma stability issues that I am not aware of. Maybe the power density of the device is too low to be practicable. But I have never heard this discussed. Any ideas?
Kinetic impact induced fusion:
http://www-pub.iaea.org/MTCD/Meetings/F … _p7-30.pdf
This requires accelerating a projectile into a target of fusion fuel. The kinetic impact generates sufficient thermal energy to trigger fusion. This method of fusion power is relatively energy efficient. However, the projectile velocity must be ~1000km/s, which makes this an inherently large scale machine. If it is possible to accelerate a projectile at 100,000g, then the accelerator must be 500km long.
We were talking about energy sources for transportation in this thread when Elderflower brought up fusion power. I said that I'm skeptical of it, and I want to explain why.
But before I do, I want to put some guardrails on this conversation. Specifically, Cold fusion, "LENR", and all that other nonsense is outside the scope of this discussion. If you think these are real then you're being fooled. But more importantly, please do not discuss them in this thread. As far as I am concerned, the only kind of fusion is "Hot Fusion" (Plus muon-catalyzed fusion). If you want to talk about energy sources that most scientists would say are impossible, please do it elsewhere.
Now, here's what I'm skeptical about as far as fusion power is concerned, and why:
I am not skeptical that it is possible to make fusion reactors work. We do it pretty frequently, and someone in the other thread also pointed out that fusion weapons generate way more energy than they consume. What we have trouble doing is controlling the reaction and directing it towards peaceful purposes. I don't believe that we are at the point, near the point, or even really approaching the point where artificial, controlled fusion is the right source of energy in any application.
The reason why I think this is that fusion is hard to make happen, much harder than fission or pretty much any other kind of energy-producing reaction. It requires all sorts of expensive and precise magnets and lasers. Current designs haven't managed to sustain fusion for long enough to generate more than the energy required to heat them up to fusion temperature, let alone to generate enough energy to make them self-heating. The basic reason is that it's extremely difficult to do so.
It's not just that current reactors are inadequate to the task (pretty much any task, to be honest). It's that no conceivable reactor using these technologies ever could be.
Let's look at a few proposed applications for fusion reactors:
Small-scale power, for example individual houses or blocks
Large-scale mobile power, for example on cargo ships
Large-scale stationary power, for the grid
Large-scale mobile power, on rockets
Basically, the important variables here are power density (W/kg) and cost ($/W and $/J).
Cost is of primary importance for the first three and secondary importance for the last one, while power density is mostly unimportant for the first and third, of secondary importance on the second, and of primary, overwhelming importance on the fourth.
If power and energy density are important, fusion is probably not the power source for you. Fusion plasmas are by their nature not very dense and compared to (for example) nuclear fission do not produce that much power per kilo. On top of that, they require a much, much heavier apparatus to control and direct the reaction. Consider: Chemical fuels sometimes ignite upon contact and once ignited a well-designed rocket engine need not move a single part to continue firing. Likewise, a rocket powered by nuclear fission needs only a minimal amount of machinery to sustain and control the fission reaction; sometimes (for a well-designed reactor) the reaction controls itself.
For similar reasons, fusion is unlikely to be cost-competitive with other technologies any time soon. Consider that a nuclear fission reaction is similar in all respects but the need for superconducting magnets or high-powered lasers to sustain the reaction. Consider that any fusion reaction will still tend to produce some amount of nuclear waste as a result of neutron release and the release of other high-energy particles, and also that a better-designed fission reactor could produce much less waste than reactors currently do, plus that solar power produces none. Consider that the intermittent but high-power nature of the reaction will require a substantial amount of energy storage. Consider that, on top of all the advanced machinery to control and sustain the fusion reaction, you will also need a lot of machinery to convert the product energy to power just like in any other system.
Perhaps fusion will eventually make sense. But not today and not any time soon.
I agree with all of the above, with one (possible) caveat. Low power density plus high capital cost would appear to make tokamak fusion an economic dead loser. That's assuming it can be made to work from a practical viewpoint. It would then need to begin the slow uphill task of trying to compete with fission from an economic viewpoint. It is a tall order, because the power density of fission reactors is 1-2 orders of magnitude greater and as Josh pointed out, they are technologically much simpler devices.
It only gets worse for fusion. Some 80% of the energy release from De-T fusion is released in the form of fast neutrons, with average energy 14.1MeV. These impact the reactor walls making them brittle and radioactive. Tokamak concepts generally envisage using steel baffle plates to absorb neutron energy which are changed every five years or so. However, the intense gamma activity of the irradiated steel will make this operationally difficult.
There is perhaps one caveat to the (probably) disastrous economics of the Tokamak. Those 14.1MeV neutrons are extremely efficient at causing secondary fission in thorium or depleted uranium blankets. Remember, the average neutron energy in a thermal or even fast reactor is too low to generate appreciable power by direct fission of 238U or 232Th. We talk about breeding nuclear fuel from these isotopes, but they do not directly work as fuel in a normal fission reactor. But with the super high energy neutrons from a fusion reactor they will directly fission, yielding energy and more (but slower) neutrons. And those super-fast fusion neutrons will fission just about any other actinide. A single fission will yield 200MeV of net energy, versus 18MeV for fusion. A fusion reaction that reaches breakeven can therefore drive a fission reactor that has net energy gain of 10. As virtually any actinide will fission in 14MeV neutrons, such a reactor would not generate long lived nuclear wastes and 1kg of U/Th put into the reactor can be expected to completely fission into short-lived fission products. What is more, at such high neutron energy the fission would yield copious secondary neutrons, which would allow very high breeding ratios in the bombarded actinide material. So a single fusion-fission hybrid could (if desired) provide enough fissile fuel for 2-3 fission reactors of the same thermal power.
All in all, we are far more likely to see fission-fusion hybrid reactors than pure fusion reactors, although it is still debatable whether a hybrid would compete economically against more conventional fast neutron reactors.
One interesting option would be a plasma core reactor, in which both fusion and fission fuels are present as mixed plasma. Fission would yield heavily charged fragments carrying about 180MeV of kinetic energy which would rapidly deposit that energy into the plasma. This heating would result in fusion between the tritium and deuterium ions, which would in turn generate super-fast neutrons, leading to even more fission. A hybrid like this could work on a chain reaction principle, even if the actinide fuel is not fissile (i.e. pure thorium). Such a device could achieve breakeven at relatively small size, because of the much greater density of actinide plasma and the short slowing down length of the fission fragments that provide most of the heating. It is therefore possible for a plasma hybrid to function as a power dense space drive, with both high acceleration and high specific impulse – the ultimate torch ship. Of course, the fission product rich exhaust would be radioactive. But until switched on, all components are low activity – Thorium and tritium.
Solar PV modules are artificially cheap at present, because Chinese state owned companies are dumping them on the western world at a price that has nothing to do with their actual manufacturing costs. This has been driven by huge overproduction combined with a slowdown in investment in China, leading to excess capacity. The dumping has pushed most European and many US panel manufacturers out of business.
https://www.nytimes.com/2017/04/08/busi … anels.html
Of course, the problem with any temporary glut is that it ultimately ends. This will happen when the Chinese economic ponzi scheme blows up or when the Chinese realise that it no longer makes sense to sell things for less than they cost to make. Question is, which will come first and when? At the rate at which Chinese debt is soaring, that is anyone's guess:
http://uk.businessinsider.com/chinese-d … ity-2017-9
European investment in renewable energy has collapsed since 2011. Chinese investment shows signs of decline as well, with 2015 looking like a peak year.
http://euanmearns.com/worldwide-investm … ow-for-it/
Many people with an ideological fixation on renewable energy are all too happy to accept recent price drops as evidence that their idealistic obsession is about to storm the world. The reality is that price reductions are occurring due to competitive pressures on manufacturers, due to Chinese state endorsed dumping, elimination of subsidies and competitive auctions.
I've heard of the flat Earth society before. But I always assumed that 'flat Earth' was satire for a more general anti-science scepticism. I had no idea these people really did believe the world was flat. I suppose the title should have been a give away! I wonder if these people ever fear falling off the edge of the world? If you believe the world is flat then traveling too far must be a constant anxiety :-)
The LOX/Methane plant is something Musk can do. Zubrin built one for a few tens of thousands of dollars back in the 1990s.
The power supply is more problematic. Musk can either take the hit and pay for the mass of the solar power system, or he can team up with another agency and develop something like this:
https://en.m.wikipedia.org/wiki/ELENA_reactor
elderflower wrote:If fluorite, or fluorapatite is reasonably common on Mars, as seems likely, mining this is going to be a lot easier than going for transmutation. Industrial use of these minerals is well established on earth and their chemistry is well characterised.
I concur with this idea; however is there any way of trasmuting oxygen-16 to fluroine-19 using neutrons from the nuclear fission of imported actinides at power generation factory on Mars? If possible, that transmutation solves in one "stone" the disposals of neutrons, disposals of oxygen atoms in Martian mining of not just fluorite, fluorapatite but also extraction for ferrous and non-ferrous metals, and resources of fluorocarbon chemicals for global warming.
Not on any practical scale. A 1GWe nuclear power reactor fissions about 1te of uranium each year. If one neutron per fission is used in transmutation, then a 1GW reactor will produce 77kg of flourine per year.
Onshore wind is already at a much lower cost than nuclear, about a third less. That means you have up to 50% of the cost of wind energy to invest in back up if nuclear is seen as the sole competitor. But this doesn't have to be full cost. Some of it can be covered by increasing output from other facilities (there is always some scope for doing that at hydro, biomass, energy from waste, and gas plants). Some of it can be covered at marginal cost by tapping into other countries energy systems e.g. hydro in Scandinavia. Some of it can be covered by storage. And some of it will at least for the next few years require some emergency back up. However, we really aren't at the stage yet where renewables require major back up.
There is a difference between 'Price' and 'Cost'. The first is what you pay; the other is what it costs to produce. Entirely different things. The auction price of wind farms is at record low levels, largely due to a price war, but also due to deflation in the price of all commodities, including steel and rare earth metals; record low interest rates and the slump in North Sea oil and gas exploration, which means that wind operators can lease ships and offshore crews at bargain rates. When these factors are coupled with the huge economies of scale that now exist in the wind industry, operators are able to offer wind contracts at ludicrously low cost levels. But they are taking huge risks. Profit margins are already low and there are clear signs that their costs are depressed.
http://www.telegraph.co.uk/business/201 … to-unthin/
Your statement regarding renewable energy not needing major back-up is incorrect at any level of renewable penetration. Every MW of intermittent electric power added to the grid must be backed up by at least 1MW of dispatachable supply. Whilst your wind turbine is generating, the backup plant will sit idle accruing labour, capital and maintenance payments. The only thing the wind turbine will accomplish is to reduce the amount of fuel being burned. The real cost of that MWh of electric power must cover both the generating cost of the wind turbine and the marginal capital, maintenance and labour cost of the backup plant. That is why Germany and Denmark have such substantially greater electric power costs.
There is no shortage of fossil fuels. The planet's got the stuff coming out of its ears and the non-existent shortage had nothing to do with the recession. If you took away the cartels like OPEC, the price would collapse worldwide but ulitmately there is a price floor associated with the real expense of getting stuff out of holes in ground or ocean floor.
The last part of your statement is true, the rest is false. The rising price of oil and other energy sources due to supply constraints in producing nations were the direct cause of the 2008 Great Recession. Whereas other resources can be substituted to a limited extent, economic output requires the expenditure of energy, because energy is the capacity to do work.
https://ourfiniteworld.com/2013/01/24/h … recession/
If conventional oil and gas were abundant, the world would not be pouring money into tight oil & gas and deep offshore condensates with much higher production costs. The marginal costs of production have steadily risen across the world since the early 2000s. Exclude unconventional oil sources, and non-OPEC oil production has tanked since 2008 and whole world conventional oil production is on a declining plateau.
http://www.artberman.com/the-crude-oil- … -peak-oil/
Price is depressed because the energy utility of these fuels put a ceiling on what consumers can afford to pay. Oil hitting $147/barrel literally bankrupted the world economy back in 2008. It never recovered. Hence the huge levels of debt that are building in most nations. It won't be long before something gives.
https://ourfiniteworld.com/2016/10/11/w … mf-missed/
Such patronising comments aren't helpful if you want a prodcutive debate.
My comments reflect all the serious analysis of the future of wind and solar energy that I have read.
If you think coal generation of electricity increased in Germany between 2015 and 2016, please provide the evidence, otherwise, please accept the evidence I presented showing it reduced.
Antius wrote:"The position in Germany is clear from the stats, so your attempts to mislead are not effective. They may be building new (less polluting) coal plants, but they are also closing down old (more polluting) ones."
Louis appears to be impervious to logic on this issue. This confirms what I suspected - that he supports the idea of rolling out a solar power economy because he finds it attractive for emotional reasons, not because it makes any real sense. I feel much the same way about single malt whisky. Each to their own I guess. At least his obsession won't give him throat cancer. It won't keep him warm either.
Maybe that was small of me. But the fact remains that for the really big decisions in life that profoundly affect people's lives, you need a better reason for advocating an option other than finding it emotionally appealing.
From a consumer's point of view, it really doesn't matter very much where electricity comes from, the service it provides is still the same and a kW is a kW. But the price really does matter a lot. And renewable electricity will always be much more expensive than historical prices of electricity from fossil fuels and nuclear power. This is because there has to be another power plant to provide back-up, which has to be paid for whether we are using it or not. This cost is reflected in the real electricity prices of countries:
https://gailtheactuary.files.wordpress. … -price.png
This is the situation where intermittent electricity represents a small proportion of total energy use, before we need to start implementing even more expensive energy storage systems.
Why is this important? Two reasons:
1. Rolling out a renewable energy economy maintains our dependence on fossil fuels, with all of the toxicity and energy security problems that that causes. Having seen the statistics on the number of deaths caused by air pollution, I am strongly opposed to anything that might prolong fossil fuel use. It is equivalent to having a Fukushima scale nuclear meltdown somewhere in world every single day.
2. On a global level, GDP is a more or less linear function of energy consumption. Expensive energy is therefore likely to suppress living standards.
The world is very close to a prolonged economic contraction resulting from falling EROI of fossil fuels.
https://ourfiniteworld.com/2017/10/18/t … ic-crisis/
https://ourfiniteworld.com/2017/11/08/w … bt-crisis/
The 2008 recession was a clear warning that fossil fuels could no longer provide sufficient energy surplus to maintain global economic growth. Since then, global growth has been weak and has come at the expense of huge increases in debt across the world. Very soon, we will be facing a global economic depression as bad as or worse than 1929. When that happens, what do you think will happen to mankind's prospects of colonising Mars?
Expensive energy, from intermittent and low-power density sources, will only make our problems worse. It is the rising cost of energy that is causing this problem in the first place. There is no point in advocating a solution that has no realistic chance of being useful. That is why I tend to be opposed to renewable energy solutions. Ultimately, the more expensive your energy is, the poorer you will be and we will need to be rich in order to get to Mars.
Governments across the world appear to see the writing on the wall. Global investment in renewable energy systems levelled off after 2011 and now shows clear signs of decline.
https://www.greentechmedia.com/articles … gs.rxBKqss
As an aside, I am not interested whether the German's provide back-up using a little more coal or a little more gas. It makes very little difference at the end of the day.
"The position in Germany is clear from the stats, so your attempts to mislead are not effective. They may be building new (less polluting) coal plants, but they are also closing down old (more polluting) ones."
Louis appears to be impervious to logic on this issue. This confirms what I suspected - that he supports the idea of rolling out a solar power economy because he finds it attractive for emotional reasons, not because it makes any real sense. I feel much the same way about single malt whisky. Each to their own I guess. At least his obsession won't give him throat cancer. It won't keep him warm either.
1t of Thorium provides about the same amount of fissionable material as about 200t of Uranium, if the reactor requires LEU.
Yes. But 1t of natural U used in a breeder reactor of some kind will provide the same amount of energy as 1t of thorium used in a breeder reactor. The difference is that you can use uranium without the complication of a breeder cycle, whereas you cannot use thorium without breeding. There is no energetic advantage in using thorium.
The molten salt reactor has some promising attributes but is no panacea. The original aircraft reactor experiments kept corrosion rates low by carefully controlling uranium oxidation state. It lasted for months, not years. For a commercial MSR you need to contain a complex molten mix of actinide and fission product halides in a stainless steel or nickel-alloy vessel for a period of decades without unacceptable corrosion levels. That is a tall order. Long-term materials degradation of primary circuit components is the number one problem that limits the life time of commercial nuclear reactors. We have decades of experience with this in LWRs - enough for some vendors to reasonably assure 80 year lifespans for their new reactor plants. It will be a long uphill struggle to achieve a commercial MSR that meet that sort of longevity. The truth is that this reactor concept is still at prototype stage and it will be a very long time before commercial units are built in any number.
Louis, lots of points here. I will try and answer as many as time allows. But you should honestly ask yourself whether your advocacy for solar power and wind power over nuclear energy are for rational reasons or are more down to the fact that you like the idea of it because it appeals to you on some emotional level. There is nothing inherently wrong with that in itself; a lot of human decisions are made on that basis, such as the design of buildings, the clothes we wear, the food we eat, etc. If we were only ever interested in practical efficiency the world would look very different. But the decision in that case isn't really about the practical benefits / dis-benefits of the two energy sources and there is no point pretending that it is.
How much do you think it costs to build a sea wall that can protect a huge installation like the one in Japan from all tsunamis in an Earthquake zone? You will be talking billions of dollars I suspect and creating all sorts of problems for the local communities.
Had the Japanese planned ahead for what should have been a foreseeable event, the cost would have been pitifully small. It would not have been expensive to protect diesel generators from the incoming tsunami and indeed, had the plant been constructed to modern standards, decay heat removal would have been accomplished through passive cooling. The failure was due to a weak safety culture. Ultimately, nuclear power plants, aeroplanes, cars, etc. are only as safe as we design them to be and things can be made better or worse by the operating organisation.
The amount of nuclear power capacity/energy produced across the world has basically flat lined now for several decades.
In the western world, the amount of generating capacity of all kinds has been flat lining since the 1980s. In the UK, Sizewell B which went critical in 1995 was the last large power plant completed that does not burn natural gas. The problem is that this has not reduced electricity costs to consumers, which have been skyrocketing.
Leaving aside green energy, why would anyone choose nuclear over gas? Nuclear power is chosen for strategic reasons and that's about it.
Who wants to be at the mercy of Mr Putin? If you are dependent upon imported gas for your electricity supply, then the risk of being cut off is hardly trivial. It also means that you must export something to these people to pay for what you are importing. The Germans have no problem in that respect, but the UK is in a much weaker position, thanks to our public industries being sold off to foreign owners by Madame Thatcher and Norman Lamont.
A LWR based nuclear electricity system will deliver substantially lower electricity costs compared to any other generating system, provided that two conditions are met: (1) Scale economies are exploited, such that continuous supply chains are developed for components and a skilled workforce is maintained; (2) The regulatory system is structured to avoid excessive extension of build times. This is how the French achieved some of the lowest electricity prices in Europe and even reached a situation where they could profitably export electricity to other nations, like the UK and Germany.
But when those two conditions are not met, you get the situation that we see at Hinkley C, which will be competitive with most other electricity sources but is clearly no bargain. It is a first of kind plant, with lots of technical issues that must be ironed out, no real UK supply chains and no established workforce capable of building it. All those things push up cost massively, especially in the UK regulatory environment.
I'll believe commercial thorium when I see it.
On this we think alike. I don't believe a thorium fuel cycle has huge benefits over a uranium cycle. It is a fertile material for one thing and will need a breeder reactor fuel cycle to work at all. It can be made to work if we need it to, but it won't be the game changer that people think it is.
China (Communist), North Korea (Communist) and Iran (Islamist) seems about the most enthusiastic builder of nuclear facilities in recent years.
Also Russia, India and South Korea. Basically, those countries with regulatory regimes that don't drag out build times and invest persistently on a scale sufficient to build up supply chains and skilled workforce, are fertile ground for new nuclear power. No power plant of any kind will be economically attractive if it takes 15 years to build and new suppliers must be established especially to cater for it. For much the same reason, you won't find many new coal power plants being built in the US. Rapid build times is one of the reasons offshore wind power looks better than it once did; but there are a lot of other fundamentals that go against it from a whole systems perspective. But more on that later.
The danger of Islamic or other terrorism, is not just about assault from outside but infiltration either through direct human agency (employees of the organisation managing the power station) or via computer hacking.
Islamic infiltration is a problem for a lot of reasons in the western world. We have handed our countries over to aggressive third-world colonists that do not share any of our values. It will cause no end of problems in years to come.
It is not impossible for terrorism to result in nuclear accidents, especially if they fly hijacked planes into nuke plants, although containment domes and LOCA protection systems are engineered to protect against these events in more modern plants. Hacking is more a problem in terms of stealing commercially or militarily sensitive information. It is unlikely to pose a direct hazard to a nuclear power plant because most electrical systems are hard wired and control computers are not web interfaced. Direct sabotage is always possible, but nuclear reactor shutdown and cooling systems have enough redundancy and inherent safety to protect against this at a local level.
Actually there was a huge reduction in use of coal for electricity generation in Gerrmany between 2015 and 2016 - a drop of more than 16 TwHs. Gas was up. That makes sense. Renewables accounted for 33%. All major European countries have plans to phase out petrol/diesel usage for road vehicles by 2040. This is only going one way.
Despite the "intermittency" issue, neither Denmark nor Germany have suffered any significant outage since renewables became a major source of electricity generation.
Both Denmark and Germany have maintained substantial coal and natural gas power generation that is capable of meeting 100% of their peak demand. They pay for this whether it is generating or not. They also 'dump' renewable electricity onto other countries grids sometimes at negative prices (they have to pay others to accept it). What the Germans have at present is essentially a coal/natural gas/nuclear based electricity system with solar and wind reducing the amount of fuel burned on an annual basis. It does reduce CO2 emissions, but they would have cheaper electricity if they simply ran their fossil plants on a baseload profile. Storage of electric power is achieved to a limited extent in Norwegian hydroelectric dams. But this has reached limits that cannot easily be expanded. There are presently no other technologies capable of storing bulk electric power in a remotely cost effective way. For this reason, it will be physically difficult for the Germans to meet much more than 1/3rd of their electricity consumption with intermittent renewable energy.
The clean up following the Fukushima disaster is estimated by the Japanese government to cost $180billion.
That was, in my view, a fairly minor disaster in a relatively unpopulated area compared with what could happen in Western Europe or Eastern USA.
Doubtful. The Fukushima accident involved fuel damage in several reactors and fuel ponds simultaneously. And Japan is hardly a lightly populated area.
It is possible to have a worse accident. But then again, all sorts of nasty things are possible if you are interested in low frequency, high consequence events. Devastating plagues, super volcanoes, meteorite strikes and less dramatic but ultimately damaging things, like an economic depression caused by poor abundance of energy. All of these things could occur on a frequency much greater than a beyond design basis nuclear accident and would kill a lot more people. What we are interested in is striking a balance that allows us to keep high living standards with the lowest risks that we can get away with. Phasing out fossil fuels and nuclear power and living on 'natural' energy may be emotionally appealing, but if it does result in much more expensive energy and lower prosperity, it will cut human life expectancy dramatically, not to mention quality of life. This would be completely counterproductive, since the assumed benefits of nuclear phase out are reducing accident risks that people fear could threaten their lives.
I carried out my own calculations of the consequences of the Fukushima accident, based upon the total activity deposited on the land, its ground shine effects and its uptake in locally grown food. I assumed that no one moved out of the area between being born and dying and that the area had average Japanese population density. I also assumed no other countermeasures. I assumed a linear relationship between radiation dose and accrued cancer risk, with a radiation weighting factor of 5-10% per Sievert depending upon age group. The results were 20,000 early fatalities – most of them occurring in the 10% of most heavily contaminated land – which amounted to a few hundred square km. Half the fatalities would occur within 50 years of the event, 75% within 70 years and 90% within 90 years. In the most heavily contaminated areas, a person living their whole life in the area, having been born at the time of the accident, would lose about 5 years of life expectancy. The average person dying from cancer as a result of the radiation would lose 20 years of life expectancy.
This gives you an idea of the worst-credible consequences of a nuclear accident in a populated area if no one attempts to move away or take any countermeasures. It all sounds quite dramatic until you realise that: (1) 200,000 people die every year in the US due to fossil fuel air pollution and globally, some 7 million people die every year due to air pollution; (2) Core damage frequency at a new nuclear power plant is something like 1 in 1million years.
At US population density levels, we would need to have a Fukushima every ten days or so to reach the mortality levels that we achieve by burning fossil fuels. In Europe, the situation is much the same, because higher population density typically means dirtier air.
The reason for all this is simple: The fission products from a nuclear reactor are a million times more toxic than coal smoke, but are produced in a million times smaller quantities. The fact that we contain them at all means that nuclear power will always be safer than fossil fuels. Even if we built reactors that were carbon copies of Chernobyl, we would still be striking a much better balance between individual risk and prosperity than if we were to generate our energy from burning coal.
A small google for "Nuclear power plant construction cost" yields,
Costs for nuclear power plants are driven primarily by the upfront cost of capital associated with construction. While a natural gas power plant could be constructed for as little as $850/kW, recent estimates put construction of a nuclear power plant at $4000/kW.
I am sure that some plants were constructed in a cheaper manner as this is dependant of size and reactors built at a single site and for the fuel type used.
Solar types have different costs for the construction..
How much does it cost to build different types of power plants in the United States?There would be also different numbers for off grid builds for any of these and if we had a viable nuclear off grid solution it just might be what I would be going with....
As I noted previously, these things are expensive because they are wrapped in red tape. Any technology can be ruined by over regulation. No matter how good it is, it will always be possible to run it into the ground.
Wind and solar power can be affordable (though not cheap) means of electricity production on Earth only if they are backed up by fossil fuel power plants, usually combined cycle gas turbines. The ff powerplant provides dispatchable power supply but fuel can be saved when wind or solar output are high. One must still meet the labour and capital costs of the ff powerplant, so the renewable powerplant is unlikely to save money, though it may reduce pollution.
100% renewable energy will never be cost competitive with nuclear energy in a LCOE calculation. This is because to provide the same product, I.e. baseload electricity, one must build 2.5 powerplants instead of one. There are ways in which a 100% renewable energy economy could work in principle, but it would be a very different way of life to what we have become accustomed to.
http://www.lowtechmagazine.com/2017/09/ … ather.html
It is easy to lose sight of the fact that wind and solar power are old technologies, much older in fact than anything that they are competing against. Before the age of steam, wind and water power were important mechanical power sources. There has never been any practical difficulty in producing power systems that generate base load electric power from 100% wind and solar energy. We could have done it in the later years of the 19th century, using a mixture of wind turbines, solar dynamic power and thermal energy storage. It would have been easier in many ways than coal power, as it would not have required mining, fuel transport or ash disposal. But it could not have produced electric power at a remotely comparable price to coal. This is a fact that has never really changed in the 140 years that it has been possible. The problem is that most renewable energy sources are inherently inferior to concentrated fuels. They have low power density and large energy investments are required to overcome intermittency and large energy losses are accrued in the process.
New nuclear energy appears relatively expensive in the western world, because (1) there are no scale economies on new nuclear power systems, few have been built in recent years; (2) nuclear energy is overburdened by authoritarian control in most countries. This stems from the fact that people are generally terrified of these things going wrong and assume that the best way of making them safe is to drown them in red tape. There is nothing inherently expensive about nuclear energy. It is expensive because we have screwed it up.
The number of neutrons yielded by fission increases with incident neutron energy. This is why breeder reactors tend to be fast reactors.
Adding shielding to a rover means adding mass to it. A rover cannot be anywhere near as well shielded as a static hab.
The Martian atmosphere already provides 200kg of shielding per square metre. Any awning that can be put up and move easily isn't going to improve that much.
Given that most of their time is going to be spent in the hab anyway, including a lot of work (analysing samples, maintaining equipment, doing experiments etc), I don't think radiation on Mars is going to be much of a problem.
I wonder if it would be practical to engineer a roof arrangement for a vehicle that would allow dirt to be shovelled onto the roof? It could be shovelled on when the vehicle stops and removed before it sets off again. If the crew drive for 8 hours per day on average, spend 8 hours asleep and 4 hours awake and inside the vehicle, a roof dirt layer could cut radiation dose somewhere between a third and half.
Regarding galactic cosmic rays - I wonder how much of the surface dose results from secondary particles generated in the Martian atmosphere? These would presumably have lower energy but higher flux. For lower energy charged particle radiation, a magnetic field would be an effective means of deflecting radiation and reducing dose rate. A magnetic field protecting a base doesn't need to be mobile and a big iron core electromagnet might be an acceptable solution. A vehicle could generate magnetic shielding whilst the engine was running and the crew could assemble a temporary dirt shield for those periods where the vehicle was not moving.
There are a lot of landslips in the Mariner valleys but there doesn't seem to be the amount of debris that you might expect. That leads me to suspect that the walls here, and maybe elsewhere on Mars, are partly composed of dirty ice. If this is so then when the collapses occur the ice can sublime and the dust can blow away, leaving a lot less rubble than might be expected.
Interesting. I can imagine this could be a real problem when it comes to siting structures on Mars. Any significant heat flux into the ground could result in a build up of subsurface pressure that is then released explosively. Even if pressure is released more gradually, the result could be subsidence. A civil engineering nightmare, like building on tundra except worse.
On the other hand, in certain areas it may be possible to generate power by pumping heat into the ground and releasing the sublimed CO2 through a gas turbine.
GW and the like evidently think there are Russians hiding behind every corner. But this sounds more like fingers in pies to me. Not really an Alt-right thing as such, more like big money behind crooked politicians.
Whenever somebody innovates in this world and produces something new, there are winners and losers. The losers in this case are the defence companies that made legacy launch vehicles and operated them at enormous profit, both Russian and US. Musk destroyed their business model. Did you really expect them to let those multi-billion dollar investments go without a fight?
It would be a mistake to write off the New Right as some kind of product of Russian antagonism. In some respects, Russia is an ideological ally in the same way that the Soviet Union was an ideological ally of the political left during the cold war. It isn't so much that Putin provides direct support to these people, more that he provides an example of a successful nationalist state. People on the right are apt to forget that Russia is a criminal fraternity, where the rule of law depends on where you are in the pecking order. But it exists outside of the Western Zionist cabal and rejects most of its values, so there are plenty of disillusioned white nationalists that respect Putin for that. They see what they want to see and like most people they make simplistic judgements and do not see the big picture.
One concern is people who live in these areas could be offended.
Colonialism still present in the North, N.W.T. premier tells Arctic Circle AssemblyDespite improved relations between the federal government and Canada's Indigenous people, northerners still get excluded from political decisions that impact their lands and livelihoods, says Bob McLeod, premier of Canada's Northwest Territories.
"Colonialism is not entirely absent," McLeod told a standing-room only crowd of international diplomats, business leaders, media and academics at the Arctic Circle Assembly, an annual event held in Iceland to foster international dialogue about the North.
"We saw [this] last December when Canada declared a unilateral moratorium on oil and gas development in the Arctic without prior consultation with either the public government of the Northwest Territories or the Indigenous people of the region," he said
So one concern is to ensure anything does not offend the people who already live there. Another concern is why this moratorium? This sounds like a wonderful way to create jobs.
In the modern world it would appear to be impossible not to offend someone. The Inuit haven't been there for much longer than the English or French (they arrived about 1500) and appear to have wiped out the previous inhabitants.
But I wonder what the motivation would be behind actually colonising the far north of Canada. The Inuit moved there because they were able to draw a living from the land. Even so, their numbers were in the thousands before European colonisation. Agriculture in the conventional sense would be impractical. Temperatures are too low to do much work outside without gloves, parkas and other heavy clothing. So what does the place provide except a surface area to live on?
Towards the polar regions of Mars, huge quantities of dry ice are present - about as much as is present in the existing atmosphere. These could be melted and then boiled to drive gas turbines, using solar or geothermal heat. Solid CO2 is kind of like a Martian fossil fuel - one that actually regenerates itself.
The energy content of liquid CO2 heated and expanded at 300K, is about 800KJ/kg. This is substantially lower than diesel or coal here on Earth (40MJ/kg and 25MJ/kg, respectively). However, is should be possible to use mild geothermal heat at polar regions to melt the dry ice in a sealed vessel at 5.1bar and -50C. The liquid can then be piped through low-carbon steel pipes to solar thermal power plants closer to the equator or a geothermal hotspot, where it would be expanded to release its stored energy. The mining of dry ice would be open cast and the power source could come from the liquid CO2 itself, expanded using some a stored heat source.
The potential for using condensed CO2 as both a primary energy source and an energy storage medium on Mars, continues to impress me. I was initially sceptical that native solar power would provide sufficient EROI. However, I am coming to realise that solutions are available on Mars that would not work on Earth. Energy storage in liquid CO2 makes solar power a lot easier to use, as we do not need to rely on energy expensive PV systems coupled to expensive Li-ion batteries for energy storage. Very simple solar thermodynamic systems can provide round the clock power with an acceptable energy return on Mars. This sort of thing works on Mars because it has a CO2 atmosphere at a temperature close to CO2 triple point and large temperature extremes across the day, providing the temperature difference needed for thermodynamic cycles. Liquid CO2 can be stored in polyethylene lined pits at ambient average temperatures at a pressure of 5.1bar.
To raise mechanical power for individual applications we do not even need to generate electricity. Simply heat the CO2 above its saturation point in a closed container and use the high pressure gas to drive compressed air tools. These are less energy efficient than electric tools, but much easier to make and are therefore more suitable for manufacture on Mars.
My previous analysis indicates that a solar thermal electric plant could be built using liquid CO2 as the heat sink and working fluid and brine as the hot thermal store.
http://newmars.com/forums/viewtopic.php?id=7884
The solar collector would gather heat during the day at about zero Celsius and would radiate heat at night at about -70 Celsius. The whole system appears to have an EROI of ~20, which is quite respectable for a power plant capable of providing a constant base load power supply. The good EROI stems from the fact that the collectors are simple unglazed clay panels, containing mild steel heat transfer pipes. Energy is stored in Polyethylene lined pits containing liquid CO2 and brine, which have very low energy cost. Again, this is possible on Mars because of its unique surface conditions. On Earth, nothing like this would work.
"Taxation: This allows taxes to be collected, but only enough to support Svalbard and the Svalbard government. This results in lower taxes than mainland Norway and the exclusion of any taxes on Svalbard supporting Norway directly. "
Louis, this implies that Svalbard is financially dependent on subsidies from the Norwegian government. In other words the colony is not financially self-supporting even though it has comparatively easy access to global trade through the sea lanes.
It has other very significant advantages over a Mars base. You can breathe the air and don't need to manufacture it. Habitats need to be insulated, but do not need to be pressurised. Food can be grown in heated (though not pressurised) greenhouses or can be fished out of the ocean. You can go outside to collect and build stuff with warm clothing, rather than a space suit. And a colony on Svalbard can import and export far more cheaply than a colony on Mars. You mention that a Mars colony can gather raw materials from the surface without ownership rights and manufacture all sorts of products. Why is this any less true for Svalbard or Northern Canada or Greenland? It seems logical to ask the question: Why would we expect a Mars base/colony to grow into a thriving civilisation when colonies in much less hostile environments on Earth fail to do so? What advantages does a Mars colony actually have that allow it to transcend the experience of small towns in hostile environments here on Earth?
Some people with a negative view of Mars's economic potential should take that on board...even though Svalbard is in a very inhospitable locale, it manages to have much lower taxes than rich and (in parts) fertile Norway. Why? Well, as with the early Mars settlement it has very few welfare and education costs.
That is mostly true for a scientific outpost in the early decades, in which the base population cycles back to Earth and there is a pre-selection process in place. The base will still require medical facilities for treatment of injury and disease, but demands upon it will be simpler and less intense given the mostly adult and working age population. It ceases to be true when the base evolves into a city, as Musk intends it to be from day 1 and after a few decades, evolves into a society with a distributed age structure.
As an aside, the decline of the Greenland Norse is a story that every prospective Mars colonist should know. It serves as a warning of what happens if you attempt to maintain a lifestyle and culture in an environment that is not suited to it. The Norse moved to the southern Greenland Fjords towards the end of the tenth century AD and maintained a pastoral lifestyle there for some three centuries. A combination of factors eventually killed them off:
1. They were dependent upon iron tools and wood and their new home did not provide any source of these;
2. The Fjord pastures were sparsely vegetated, and bovines could not thrive in this environment. The main diet of the Norse was milk, cheese and beef, which they were able to substitute with Sea Lion meat. They made no attempt to eat local fish, presumably for cultural reasons. Their landed lifestyle provided barely enough calories to keep them healthy;
3. A little ice arrived in the late Mediaeval period. This resulted in three problems: (a) The pasture in the fjords retreated, reducing food supply; (b) The Norse were cut off from their Scandinavian homeland; (c) Migratory animal populations shifted.
4. The Thule Indians expanded into Greenland at about the same time. The Norse warred with them, but being few in number and without iron weapons, they took heavy losses.
Generally, their misfortune can be summarised as a failure to adapt properly to a new environment. Their diet and general way of life was not suited to the high arctic environment and they were unable or unwilling to adapt their way of life in a way that would allow them to subsist in such a poor environment. Mother Nature made things worse by suddenly changing climate and cutting their supply lines.
In the modern world, we survive in these environments not so much by adapting to them, but by supporting a predetermined lifestyle with technology. Even the Inuit live in oil heated houses, wear commercial clothing, use petrol powered vehicles, etc. We can do this and the Norse could not, because abundant fossil fuels provide a very cheap storable, portable energy source and allow the manufacture of complex products and their distribution through reliable global supply lines. This way of life will survive as long the energy sources supporting it continue to function at an acceptable energy return. It works because these people are able to trade something that allows them to afford the things that they need to survive.
The problem we have with colonising Mars is that neither option seems to work very well. The high cost of transport means that we cannot live well at the end of supply lines from Earth. Yet the environment itself is poorer even that the Arctic – there is no liquid water, no flora, not even air that we can breathe. A lot of technology and infrastructure are needed just to survive. Yet opportunities for exports to pay for imports are weak at best.
I don't know if I'd go as far as to say that those cultures are gone, but there's a lot of land up there and we don't need to make the same mistakes as past settlers and colonists did.
I agree with GW that a big benefit will be to the communities at the margins, where farming was previously untenable and maybe less so, but I'm interested in the communities of the arctic coast because they're more different and more Mars-like. I definitely agree with Terraformer that the high arctic is a sort of Mars-on-Earth, with many of the same drawbacks and benefits (minus being on a different planet).
The four largest cities north of the arctic circle are Murmansk, Russia (population 307,257), Norilsk, Russia (175,365), Tromsø, Norway (71,295) and Vorkuta, Russia (59,231). Utqiaġvik, Alaska (Formerly known as Barrow) is the largest town outside of Norway and Russia with just over 4,000 residents, plus a few thousand transient oil workers.
So in answer to your original question, these places are inhabited already, albeit lightly. So it is clearly worth inhabiting them, assuming you want the resources and way of life that that implies.
Traditional cultures lived off of the animal life of the land, an approach that spread them thinly and required migratory settlements. The people living there now have already largely abandoned that way of life and live in permanent settlements eating mostly imported food. Not a very sustainable approach, but the productivity of the land is extremely limited and it will not naturally support large numbers of people. To do that requires concentrated artificial energy sources. Mostly fossil fuels up to now, with some contribution from nuclear energy. More later.
The points Antius makes in his posts (if you can call them that) are both manifestly untrue and clearly based on animus. The latter explains the former, insofar as their total lack of objective factual analysis represents a stunning departure from what I've come to expect from Antius.
Given the above, it would be both a waste of time and a misconstruction of the statements in the posts to respond with factual arguments. They are statements of opinion, where the opinions being stated are rather vile and belong in the trash can of history along with all sorts of other primitive, discarded ideologies.
I can prove everything that I say Josh. But I get the feeling that proof is the last thing that you would want. Some ideas are precious to people and form part of their emotional security. This is why ideologues will always attempt to shutdown debate. The truth is painful to them. It is not logical and it undermines democratic principles, which rest upon the ideal that all ideas are subject to debate and challenge and must be proven before they can be accepted. But it is human nature and it is clearly where we are. It is exhausting and pointless trying to argue with people that do not want to see the truth.
Trying to refute Marxist ideals is rather like trying to disprove a religion. No matter how hard you try and however convincing your evidence, you will never succeed in convincing the ideologue, because the the ideals that you challenge are an emotional crutch for that person. That is why they start name calling and insist that you are wrong, whilst providing no evidence of their own.
