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#1 2019-10-30 15:18:24

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 519

Low-cost nuclear reactors

In recent discussions it was established that human life on Mars will be very dependent upon abundant, low cost energy.  This will be needed in the form of heat of all qualities and electricity.

http://newmars.com/forums/viewtopic.php?id=9187

Initial estimates indicate that that electricity consumption may need to be 10 times greater than North America average, as power is needed for the production of propellant, food, water, metals and the mining of ores.  In addition, large quantities of low-grade heat are needed for the production of water from subsurface ice and potentially, the heating of greenhouses.  A city of 1million people, as envisaged by Musk by the end of the 21st century; will require up to 10GWe of power on a continuous basis.  For such large quantities of power to be affordable in any realistic economy, it must be provided cheaply, for the simple reason that more energy is needed to meet basic functions on Mars.

Power in such large quantities can be provided only by using nuclear reactors.  Providing 10GWe of time averaged power on Mars using solar power sources, would require a solar power plant covering several hundred square kilometres.  Large scale civilisation on Mars will require the use of nuclear power on a scale that has yet to be replicated on Earth.

I have started this topic to explore how we could develop nuclear power both cheaply and on a huge scale on Mars.  Specifically, what technologies we will use; which systems will be imported from Earth; the optimal size of units, etc.

Last edited by Calliban (2019-10-30 15:35:20)


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#2 2019-10-30 16:03:42

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 519

Re: Low-cost nuclear reactors

The RBMK reactor is much maligned in the Western world, due to it's involvement in the Chernobyl nuclear accident.  In spite of the known problem of positive coolant void reactivity coefficient; the RBMK had some significant advantages over western light water reactors.  These are seldom discussed, but are highly relevant here.

1. The RBMK is a pressure-tube boiling water reactor.  This is a direct cycle, in which water boils within the core and steam is dried and passes directly to the main turbines.  This means that no steam generators are needed; merely a steam drum.

2. As a pressure-tube reactor, the RBMK does not require a pressure vessel.  The fuel is contained in zirconium boiler tubes running through a lightly pressurised graphite moderator stack.  The pressure vessel for a PWR or BWR is a very expensive and difficult to fabricate component.  It becomes progressively more difficult to construct, the larger it is, as wall thickness increases.  To scale up an RBMK, it is relatively simple to increase the size of the moderator stack and simply add more fuel channels.

3. The RBMK is a graphite moderated reactor, with water used for cooling, not moderation.  This results in much better neutron economy than a typical Western light water reactor, allowing the use of lightly enriched or even natural uranium as fuel.

These collective advantages allowed the cash-strapped Soviets to build extremely large and powerful reactors quickly and at low cost.  The Ignalina reactors were built in the late 1970s and had power of 1500MWe; far more powerful than any western reactor in operation at that time.  RBMK units were planned with power up to 2400MWe.  Such scales are possible because reactor power can be increased simply by increasing the number of fuel channels.  As was noted previously, the economics of nuclear power reactors tend to improve with increasing scale.

Of course, the RBMK has design deficiencies which make it a dubious choice for future power generation.  It is noteworthy however, that whilst the positive void coefficient of the RBMK did directly contribute to the chernobyl accident; the real cause had more to do with a complete absence of safe operating culture.  The reactor exploded during at experiment, during which control rods were fully withdrawn to burn off a xenon peak and trip settings were deliberately disabled.  Most nuclear reactors would be dangerous under those conditions.  It is unlikely that a PWR would survive a prompt criticality without significant fuel damage.  In a modern design, we would coolant feed water with low temperature trip settings.  We would design control rods without graphite follwers and design the control rod motors to allow rapid insertion of control rods into tye core.  Most importantly, we would not be reliant on manual operator control.

If we can import enriched uranium from Earth, then we can adjust the concept of a pressure tube reactor to use a calandria filled with light water, rather like a CANDU. This would eliminate the coolant void temperature coefficient problem of the RBMK and would allow a far more compact core, without sacrificing the benefits of a pressure tube boiling water reactor.

Last edited by Calliban (2019-10-30 16:23:34)


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#3 2019-10-31 12:30:55

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 519

Re: Low-cost nuclear reactors

The Chinese are developing a low-temperature light water reactor for district heating purposes.

https://www.nextbigfuture.com/2017/12/c … lants.html

This is very cheap, because a reactor that heats water to ~100C does not need a pressure vessel and corrosion rates at such low temperatures are low enough that material selection becomes easy.  There is very little danger from a loss of coolant accident, as the whole reactor can be located at the bottom of a deep pool at ambient pressure with huge heat capacity. 

A bulk low-grade nuclear heat source on Mars would be a relatively easy thing to build.  We could use Mars mined natural uranium to fuel a graphite moderated low-temperature reactor.  Cladding and fuel channels could all be made from aluminium if temperatures don't get much above 100C.  Because Martian ambient temperatures are lower than those of Earth, a low temperature reactor could still generate electricity at a moderate efficiency, by using something other than water as a working fluid.  But a water cooled and entirely heat producing reactor, would be useful in water mining and greenhouse heating activities.


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#4 2019-10-31 15:01:20

louis
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From: UK
Registered: 2008-03-24
Posts: 5,868

Re: Low-cost nuclear reactors

There is nowhere on Earth a "low-cost" nuclear reactor. There are just differently expensive nuclear reactors, which is why when the market is left to choose it opts for fossil fuels, hydro or, increasingly, wind and solar.

The situation on Mars might be slightly different in that you can perhaps invest less in safety owing to the absence of large human populations (or, so we are told, other organic life).  However  the incidence of global dust storms would appear to create the risk of radioactivity being quickly spread around Mars.

I really can't see why we would go to the bother of manufacturing or importing nuclear reactors on Mars, when there is a readily available energy source which is practical, cheap and effective ie photovoltaic power (with methane-oxygen as the primary energy storage method).


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#5 2019-10-31 15:16:56

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 519

Re: Low-cost nuclear reactors

louis wrote:

There is nowhere on Earth a "low-cost" nuclear reactor. There are just differently expensive nuclear reactors, which is why when the market is left to choose it opts for fossil fuels, hydro or, increasingly, wind and solar.

The situation on Mars might be slightly different in that you can perhaps invest less in safety owing to the absence of large human populations (or, so we are told, other organic life).  However  the incidence of global dust storms would appear to create the risk of radioactivity being quickly spread around Mars.

I really can't see why we would go to the bother of manufacturing or importing nuclear reactors on Mars, when there is a readily available energy source which is practical, cheap and effective ie photovoltaic power (with methane-oxygen as the primary energy storage method).

Lol.  The Chinese are doing a very good job of building reactors at low prices.  The French did until they started messing with the over-complex EPR.  In most major developed economies this is one of the largest sources of baseload electricity and is the cheapest.

Louis wants to build a solar power economy on planet with half of Earthly sunlight, on which we need 10 times as much electricity per capita.  If we cannot make this work on Earth, what hope is there for Mars?


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#6 2019-10-31 16:44:02

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 19,657

Re: Low-cost nuclear reactors

You would think that the cost would come down since the levels of protest are by and far less but its the legal battles, law suits over regulations and connectivity to the grid for maintenance is why we are charged so much for the power and for the plant cost without regards to the design type.
China is chaina with regards to what it costs for all of what they do within there borders. Its not like they are exporting power to the grid....

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#7 2019-10-31 16:46:07

louis
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From: UK
Registered: 2008-03-24
Posts: 5,868

Re: Low-cost nuclear reactors

Nuclear power in China supplies about 2% of that country's electricity generation, compared with 58% coal and 5% solar. Hardly suggests that nuclear is the cheapest source in China. By 2040 it is expected that solar will quadruple to 22% and nuclear will double to 4%.  Again, that does not suggest to me that the Chinese think nuclear power for electricity is the future. By 2040 it is expected that 55% of electricity generation will come from solar, wind and hydro, in that order.

Calliban wrote:
louis wrote:

There is nowhere on Earth a "low-cost" nuclear reactor. There are just differently expensive nuclear reactors, which is why when the market is left to choose it opts for fossil fuels, hydro or, increasingly, wind and solar.

The situation on Mars might be slightly different in that you can perhaps invest less in safety owing to the absence of large human populations (or, so we are told, other organic life).  However  the incidence of global dust storms would appear to create the risk of radioactivity being quickly spread around Mars.

I really can't see why we would go to the bother of manufacturing or importing nuclear reactors on Mars, when there is a readily available energy source which is practical, cheap and effective ie photovoltaic power (with methane-oxygen as the primary energy storage method).

Lol.  The Chinese are doing a very good job of building reactors at low prices.  The French did until they started messing with the over-complex EPR.  In most major developed economies this is one of the largest sources of baseload electricity and is the cheapest.

Louis wants to build a solar power economy on planet with half of Earthly sunlight, on which we need 10 times as much electricity per capita.  If we cannot make this work on Earth, what hope is there for Mars?


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#8 2019-10-31 17:42:53

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 519

Re: Low-cost nuclear reactors

A solar power plant in China, is basically a coal burning power plant.  The solar plant is useful in so far as it reduces coal consumption in a legacy powerplant by 20%, reducing pollution and stretching coal resources a little further (the Chinese are past Peak Coal).  It isn't much of deal, as the coal plant still has operating and maintenance costs, but tye solar power does reduce the fuel bill.  All in all, it will be more expensive than the coal plant on its own, but the reduced pollution is something worth paying a little extra for.  It's a terrible deal if you have to build the coal plant as a dedicated backup powerplant.  The same is true for wind power.


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#9 2019-11-01 02:26:12

louis
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From: UK
Registered: 2008-03-24
Posts: 5,868

Re: Low-cost nuclear reactors

The trend is all one way:

https://science.sciencemag.org/content/365/6449/108

Solar plus storage is already competitive. Will the cost of solar and battery storage rise in the future? No, it will fall...and the fall might be dramatic as we have seen over the last 20 years. There is no way that nuclear can compete with this in a modern democratic society where you can't take safety shortcuts.

Calliban wrote:

A solar power plant in China, is basically a coal burning power plant.  The solar plant is useful in so far as it reduces coal consumption in a legacy powerplant by 20%, reducing pollution and stretching coal resources a little further (the Chinese are past Peak Coal).  It isn't much of deal, as the coal plant still has operating and maintenance costs, but tye solar power does reduce the fuel bill.  All in all, it will be more expensive than the coal plant on its own, but the reduced pollution is something worth paying a little extra for.  It's a terrible deal if you have to build the coal plant as a dedicated backup powerplant.  The same is true for wind power.


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#10 2019-11-01 10:50:50

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 519

Re: Low-cost nuclear reactors

Once again, Louis sees what he wants to see.

Lazard's November 2018 analysis of levelised cost of storage for utility grade solar and lithium ion storage, gives a median cost of $124/MWh.  This is the most respected and often cited source by green techies of levelised cost of energy, although it does not give us much clue as to where cost reductions are coming from and whether they are sustainable long term.  It is really just looking at trends and projecting them into the future.

https://www.lazard.com/media/450774/laz … vfinal.pdf

But note from Lazard's analysis, that Lithium ion battery storage only accounts for about 2 hours of full capacity for utility scale PV and storage.  This makes the battery useful for smoothing frequency fluctuations and reducing the slew rate long enough to get enough spinning capacity (natural gas and coal) back online.  It is not intended to work as a standalone solution.  For that to happen, storage would need to be at least a couple of orders of magnitude greater than is presented here.  It would need to cover lulls in solar capacity lasting for days and maybe, dependent upon location, seasonal fluctuations in solar energy abundance.

As the required energy storage capacity increases, the cost per MWh increases geometrically.  This is because in addition to being larger, the energy store will fully discharge less frequently and is therefore less well utilised.  For example, compare the situation of a two batteries, both designed to produce 1kW of power; one storing power for an hour and the other storing a whole week of power.  The first battery will regularly charge and discharge on an hourly basis and over the period of a year; it will have stored and discharged up to 8766kWh of electricity.  The second battery operating in the same system will store and discharge exactly the same amount of energy, given that it is discharging at the same rate.  But it would need to be 168 times larger and commensurately more expensive to store a week of power.  Energy storage in batteries is only affordable in small quantities acting over short periods of time.  It is about avoiding crashing the grid before compensating powerplants can be brought online.

It is the need for large volume, long-term energy storage that has led to many green-tech enthusiasts citing liquid hydrogen as an energy storage medium.  Although this is relatively inefficient and expensive, it allows energy to be stored in liquid form in insulated tanks and is therefore better suited to long-term storage.  Louis's methane-oxygen system is an attempt to do the same thing, but with the extra step of reacting the hydrogen with CO2 in a chemical reactor to make methane, which is then cooled to cryogenic temperatures and stored in an austenitic stainless steel or aluminium tank.  None of these things actually happen at present, largely because they are not even close to being competitive with conventional generation.  What does happen is the solar power plant runs alongside coal or natural gas burning power plants that ramp up production when the sun isn't shining, or when clouds reduce output.  So the solar power plant has the effect of modestly reducing fuel consumption in the coal or NG plant, which is what I was alluding to before.  The need to continue using fossil fuels to provide backup for wind and solar, goes some way towards explaining why Germany burns more coal than any other country in Europe.  Not very green at all.

https://www.zerohedge.com/energy/where-europe-runs-coal

Is solar power really the cheapest form of energy, before we take into account backup and storage?  I suppose that depends upon who you ask.  About 80% of solar panels sold in the US market are made in China and the Chinese have faced a number of lawsuits for dumping in order to corner the market and maintain employment back home.  Solar is also heavily subsidised and subsidies are largely hidden.
https://stopthesethings.com/2018/08/23/ … subsidies/
Perhaps most telling of all, renewable energy market penetration shows a positive correlation towards increasing electricity cost.
https://wryheat.wordpress.com/2015/08/0 … skyrocket/

If we attempt to carry out a solar energy revolution on Mars, we will have to face all of these problems, on a planet where there are no fossil fuels; where sunlight is about as intense at the equator as it is in Alaska and where we need 10 times more electricity just to survive.  Any takers?


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#11 2019-11-01 17:18:07

louis
Member
From: UK
Registered: 2008-03-24
Posts: 5,868

Re: Low-cost nuclear reactors

No one I know is saying that solar plus storage is the cheapest alternative across the board...storage at 12 cents per KwH is actually already quiite cheap.

The issue really is what solar plus storage will be in 10 or 20 years' time.


Calliban wrote:

Once again, Louis sees what he wants to see.

Lazard's November 2018 analysis of levelised cost of storage for utility grade solar and lithium ion storage, gives a median cost of $124/MWh.  This is the most respected and often cited source by green techies of levelised cost of energy, although it does not give us much clue as to where cost reductions are coming from and whether they are sustainable long term.  It is really just looking at trends and projecting them into the future.

https://www.lazard.com/media/450774/laz … vfinal.pdf

But note from Lazard's analysis, that Lithium ion battery storage only accounts for about 2 hours of full capacity for utility scale PV and storage.  This makes the battery useful for smoothing frequency fluctuations and reducing the slew rate long enough to get enough spinning capacity (natural gas and coal) back online.  It is not intended to work as a standalone solution.  For that to happen, storage would need to be at least a couple of orders of magnitude greater than is presented here.  It would need to cover lulls in solar capacity lasting for days and maybe, dependent upon location, seasonal fluctuations in solar energy abundance.

As the required energy storage capacity increases, the cost per MWh increases geometrically.  This is because in addition to being larger, the energy store will fully discharge less frequently and is therefore less well utilised.  For example, compare the situation of a two batteries, both designed to produce 1kW of power; one storing power for an hour and the other storing a whole week of power.  The first battery will regularly charge and discharge on an hourly basis and over the period of a year; it will have stored and discharged up to 8766kWh of electricity.  The second battery operating in the same system will store and discharge exactly the same amount of energy, given that it is discharging at the same rate.  But it would need to be 168 times larger and commensurately more expensive to store a week of power.  Energy storage in batteries is only affordable in small quantities acting over short periods of time.  It is about avoiding crashing the grid before compensating powerplants can be brought online.

It is the need for large volume, long-term energy storage that has led to many green-tech enthusiasts citing liquid hydrogen as an energy storage medium.  Although this is relatively inefficient and expensive, it allows energy to be stored in liquid form in insulated tanks and is therefore better suited to long-term storage.  Louis's methane-oxygen system is an attempt to do the same thing, but with the extra step of reacting the hydrogen with CO2 in a chemical reactor to make methane, which is then cooled to cryogenic temperatures and stored in an austenitic stainless steel or aluminium tank.  None of these things actually happen at present, largely because they are not even close to being competitive with conventional generation.  What does happen is the solar power plant runs alongside coal or natural gas burning power plants that ramp up production when the sun isn't shining, or when clouds reduce output.  So the solar power plant has the effect of modestly reducing fuel consumption in the coal or NG plant, which is what I was alluding to before.  The need to continue using fossil fuels to provide backup for wind and solar, goes some way towards explaining why Germany burns more coal than any other country in Europe.  Not very green at all.

https://www.zerohedge.com/energy/where-europe-runs-coal

Is solar power really the cheapest form of energy, before we take into account backup and storage?  I suppose that depends upon who you ask.  About 80% of solar panels sold in the US market are made in China and the Chinese have faced a number of lawsuits for dumping in order to corner the market and maintain employment back home.  Solar is also heavily subsidised and subsidies are largely hidden.
https://stopthesethings.com/2018/08/23/ … subsidies/
Perhaps most telling of all, renewable energy market penetration shows a positive correlation towards increasing electricity cost.
https://wryheat.wordpress.com/2015/08/0 … skyrocket/

If we attempt to carry out a solar energy revolution on Mars, we will have to face all of these problems, on a planet where there are no fossil fuels; where sunlight is about as intense at the equator as it is in Alaska and where we need 10 times more electricity just to survive.  Any takers?


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#12 2019-11-01 20:06:43

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 19,657

Re: Low-cost nuclear reactors

Where are you buying your batteries that are "12 cents per KwH" as the power companies are just shy of that.

As you could buy enough batteries for a dollar to supply power for your home for the day....

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#13 2019-11-02 02:47:47

Terraformer
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From: Lancashire
Registered: 2007-08-27
Posts: 3,304
Website

Re: Low-cost nuclear reactors

No one I know is saying that solar plus storage is the cheapest alternative across the board...storage at 12 cents per KwH is actually already quiite cheap.

I don't think that's the cost of the storage, but the cost of the energy after storage is taken into account. Significantly higher than the cost of electricity from other sources.


"I guarantee you that at some point, everything's going to go south on you, and you're going to say, 'This is it, this is how I end.' Now you can either accept that, or you can get to work." - Mark Watney

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#14 2019-11-02 04:04:19

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 519

Re: Low-cost nuclear reactors

The problem is that the batteries can only provide a few hours of storage at most.  They are there to prevent sudden changes in output from crashing the grid due to frequency changes.  It is a relatively expensive way of storing energy, but has the advantage of rapid discharge rate and can therefore respond well to short-term peaks and troughs.  Large scale energy storage typically relies on pumped hydro, CAES or thermal storage.  Hydrogen has been discussed, but isn't really very practical.  It is difficult to scale any storage solution to cover days worth of lulls without pushing costs to ridiculous levels, which is why wind and solar plants need to be paired with backup power plants, usually running on natural gas.  Even before storage, solar panels are only as cheap as they are, because of hidden subsidies and dumping.

We cannot make this work as a scalable solution here on Earth.  There is no fossil fuel on Mars and even if there were, there is no air to burn it in.  A Martian civilisation would need about 10 times as much electrical power to provide food, water and manufacture habitation space.  Musk's proposed city of 1million people would need round the clock power of about 10GWe.  This energy needs to be delivered cheaply if Martians are to enjoy a decent standard living. And sunlight is half the intensity that it is on Earth.  This would suggest to me that solar power is only suitable as a small scale supplemental energy source, where we need modest amounts of power without a grid connection and cost is not the driving factor.

If nuclear fusion comes online in the timescale of Musk's vision, then it may be the solution to the problem.  If not, then the Martians will need to build powerful nuclear reactors, cheaply and quickly.  I raised the idea of building RBMK reactors, burning natural uranium mined from Mars.  But there are other concepts that could work as well.  RBMK is a graphite moderated, pressure tube boiling water reactor.  No steam generators or pressure vessel is needed; it can burn natural uranium and it can be scaled to virtually any power level necessary by adding more fuel channels and increasing the core diameter.  Hence this reactor can provide large amounts of electricity very cheaply.  We need to design these reactors to be safe of course.  I don't think that there is any need to repeat the design mistakes of the Soviet union.

Last edited by Calliban (2019-11-02 04:17:57)


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#15 2019-11-02 05:52:41

louis
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From: UK
Registered: 2008-03-24
Posts: 5,868

Re: Low-cost nuclear reactors

In countries where we already have a methanee/natural gas infrastructure the obvious solution is to use wind and solar energy to manufacture methane from air and water to act as the buffer for extended periods of low wind and solar energy. You can use the manufactured methane to power your existing fossil fuel methane generators.

The economics are not quite there yet I would say but with wind and solar often coming in under 2 cents per KwH, they can't be far off.
In a country like the UK, you'd probably need to produce about 5% of your electricity generation over a year from manufactured methane. Remember, as well that a lot of levelling out of supply can be achieved through continental grids. The UK is already linked to France and Norway by grid cables and there are plans to connect up to Iceland as well.

The economics on Mars will be entirely different for the foreseeable future. Earth has billions of people, and lots of energy choices; Mars will have only thousands and the energy choices are limited. On Mars key considerations are:-

(a) Do you import your energy system or do you manufacture it on Mars?

(b) How much labour is required to go into your energy system on Mars?

The only nuclear power systems I know of existing in the real world are labour intensive in terms of manufacturing, monitoring and maintenance (which is why they end up being so expensive on Earth).  There are claims that we can have automated nuclear power; if those claims are realised, that might address some of the concerns regarding labour input. However, by contrast we do already have automated PV - no one needs to stand over a PV panel watching it work.

I think manufacture of PV panels on Mars could be highly automated, and of course would not involve any major health risks. This would mean that from an early stage - I would say within 6 years, if it was treated as a key goal - the Mars settlement could become energy independent of Earth, a key step on the path towards potential self-sufficiency, which has to be the goal for all those interested in Mars as a second home for humans.  This would involve PV manufacturing equipment being shipped to Mars in the first instance and then also, designs for 3D printing and CNC lathe manufacture of the component parts of a PV manufacturing facility, so that Mars can not only produce PV panels but also the factories that make the PV panels. Investing in automation on Mars makes a lot of economic sense, because labour power is so restricted.

A small Mars community will also be able to manufacture methane generators and methane/oxygen isolation equipment, as well as chemical batteries.

The fact that for the foreseeable future a Mars community will be manufacturing both methane and oxygen as propellant means that  PV plus methane storage system will dovetail nicely with the other major economic activity on Mars.

I don't rule out nuclear power on Mars entirely. It may over time come to have a role to play in both food production and terraformation. But that is probably 20 or 30 years down the line.


Calliban wrote:

The problem is that the batteries can only provide a few hours of storage at most.  They are there to prevent sudden changes in output from crashing the grid due to frequency changes.  It is a relatively expensive way of storing energy, but has the advantage of rapid discharge rate and can therefore respond well to short-term peaks and troughs.  Large scale energy storage typically relies on pumped hydro, CAES or thermal storage.  Hydrogen has been discussed, but isn't really very practical.  It is difficult to scale any storage solution to cover days worth of lulls without pushing costs to ridiculous levels, which is why wind and solar plants need to be paired with backup power plants, usually running on natural gas.  Even before storage, solar panels are only as cheap as they are, because of hidden subsidies and dumping.

We cannot make this work as a scalable solution here on Earth.  There is no fossil fuel on Mars and even if there were, there is no air to burn it in.  A Martian civilisation would need about 10 times as much electrical power to provide food, water and manufacture habitation space.  Musk's proposed city of 1million people would need round the clock power of about 10GWe.  This energy needs to be delivered cheaply if Martians are to enjoy a decent standard living. And sunlight is half the intensity that it is on Earth.  This would suggest to me that solar power is only suitable as a small scale supplemental energy source, where we need modest amounts of power without a grid connection and cost is not the driving factor.

If nuclear fusion comes online in the timescale of Musk's vision, then it may be the solution to the problem.  If not, then the Martians will need to build powerful nuclear reactors, cheaply and quickly.  I raised the idea of building RBMK reactors, burning natural uranium mined from Mars.  But there are other concepts that could work as well.  RBMK is a graphite moderated, pressure tube boiling water reactor.  No steam generators or pressure vessel is needed; it can burn natural uranium and it can be scaled to virtually any power level necessary by adding more fuel channels and increasing the core diameter.  Hence this reactor can provide large amounts of electricity very cheaply.  We need to design these reactors to be safe of course.  I don't think that there is any need to repeat the design mistakes of the Soviet union.


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#16 2019-11-02 06:56:58

tahanson43206
Member
Registered: 2018-04-27
Posts: 3,456

Re: Low-cost nuclear reactors

For Louis re #15

While this topic is (I believe from the title) about nuclear reactors, your spirited defense of manufacture of methane is a point of view I find interesting, and worth considering at greater depth, in a new topic if that seems appropriate.

In the mean time, I'd like to ask if you are in a position to compare and contrast the economics of using ammonia as an energy carrier vs using methane as you propose.  I'm under the impression ammonia would turn out to be more cost effective, but I agree that methane is a good choice because the entire infrastructure is already in place, from gigantic ships for shipment between continents to the last little burner in a gas stove in a home somewhere.

However, with the deliberate intention of restoring the topic, I would like to see an analysis of what it would take to use an existing nuclear power plant to make methane.  In the age of fracking, methane is selling at a price point which might make the nuclear reactor supply approach impractical, but inevitably all stored reserves of fossil fuel are going to be exhausted.

(th)

Last edited by tahanson43206 (2019-11-02 19:25:50)

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#17 2019-11-02 09:23:55

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 19,657

Re: Low-cost nuclear reactors

What Louis is trying to convey is a tiered approach to energy creation for supply to its customers. Its the type which is needed for anything but power that leads to secondary uses for some of the sources. Of course we can use electrical to produce heat and thats where the lines start to blur.

Its our ability to change energy sources from one form to another that makes mars a challenge as there is only the small vapor trails of methane coming out of mars to start with unlike earth that has oil, coal, water. natural gas....as a reserve and starting point to create energy in the form of electrical. Its the changing of those other forms to electrical that makes life more pleasurable and prosperus on earth.

Its going to take any system that makes electrical which is going to be the key for mars. So for storage on mars its finding out if the methane trials are more substanial which will start the use of reserves for energy and so forth.

I have been hearing a Penzoil commercial which states that they use natural gas to make sythetic oil for lubrication and I would wonder if doing the same for mars would be another way to create a liquid reserve.

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#18 2019-11-02 10:54:28

knightdepaix
Member
Registered: 2014-07-07
Posts: 236

Re: Low-cost nuclear reactors

How about...
1) nuclear heat and electricity cogeneration using radioisotope thermoelectric generators modules on imported nuclear waste from Earth?
1.1) electricity
1.2) heat for heating in settler residence, greenhouses and endothermic reactions of turning carbon dioxide and water to oxygen, carbon monoxide and hydrogen. The latter two chemical compounds could be reheated in some form of heat exchange and yield hydrocarbons. The low temperature lubricants and plastics could be made. Hydrogen-1 itself can be used in the cogeneration.
1.3.1) One radioisotope and protons generates energy in one module. The stable daughter isotope is recycled. Bromine can be one daughter isotope and contribute to make vinyl bromide monomer for polyvinyl bromide plastics without mining for native chlorine.
1.3.2) Silver can be another stable daughter isotope and the choice of native metals for electric wires are iron, silver and aluminum.

2) solar panel on an Mars orbit. Microwave transmission would send the energy to the factory of 1.2) to heat ice into water or steam. Microwaving water is very well known and functioning very well in principle in many homes.

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#19 2019-11-02 11:16:27

knightdepaix
Member
Registered: 2014-07-07
Posts: 236

Re: Low-cost nuclear reactors

To louis specifically,

RickSmith wrote:

My intention is to have this thread answer common questions about Mars and Terraforming with indexes to appropriate topics.
--3) A third problem is radiation.  Earth's magnetic field directs much of the ionizing radiation from the sun to the polar regions.  Mars has no strong magnetic field so these are spread over the whole planet.  Second the atmosphere is too thin to stop cosmic rays.  Third there is no ozone layer ( O3) so dangerous ultraviolet light sterilizes the surface.

Can solar panel be made to turn those dangerous UV into electricity and/or heat?

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#20 2019-11-02 11:58:30

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 519

Re: Low-cost nuclear reactors

Like I said before, the 2¢/kWh is the cost after subsidy, hidden or otherwise.  It is not representative of the real cost of electricity.

https://wryheat.wordpress.com/2015/08/0 … skyrocket/

Mars needs cheap electricity.  Basic living space and agricultural land must be encased in a pressurised shell of steel, which is reduced from ore using electrolytic hydrogen.  Water must be mined from the ground using as much energy as it takes to make concrete on Earth.  This is not something that can be done with solar panels.

Last edited by Calliban (2019-11-02 12:37:38)


Interested in space science, engineering and technology.

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#21 2019-11-02 13:01:37

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 19,657

Re: Low-cost nuclear reactors

solar for uv is possible but its a different chemistry than the normal solar. These were covered in the high temperature topics for solar in heliostacks.

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#22 2019-11-02 16:33:24

louis
Member
From: UK
Registered: 2008-03-24
Posts: 5,868

Re: Low-cost nuclear reactors

I understand that PV panels do use some of the UV radiation  - and could be designed to use more of it on Mars. I think it's more about cost than a technical challenge, but I might be wrong!


knightdepaix wrote:

To louis specifically,

RickSmith wrote:

My intention is to have this thread answer common questions about Mars and Terraforming with indexes to appropriate topics.
--3) A third problem is radiation.  Earth's magnetic field directs much of the ionizing radiation from the sun to the polar regions.  Mars has no strong magnetic field so these are spread over the whole planet.  Second the atmosphere is too thin to stop cosmic rays.  Third there is no ozone layer ( O3) so dangerous ultraviolet light sterilizes the surface.

Can solar panel be made to turn those dangerous UV into electricity and/or heat?


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#23 2019-11-02 17:09:25

louis
Member
From: UK
Registered: 2008-03-24
Posts: 5,868

Re: Low-cost nuclear reactors

Well this is where you get into tail-chasing. I am not denying there might be a subsidy involved in the sub-2 cents per KwH figure but it did relate to SW USA where PV is among the most efficient in the world. But equally coal and gas don't pay for the air pollution they cause or their carbon emissions (if you believe that is a real cost factor in terms of climate change).

PV levelised price has fallen 88% in ten years, while nuclear has fallen about 13%. The cheapest PV is now about 50% cheaper than the cheapest nuclear and is now on a par with gas. As most analysts agree, there doesn't seem to be anything to stop further significant falls in the price of PV, whereas the cost of getting gas out of the ground, liquefying it and transporting it thousands of miles is not going to reduce much if at all.

The cost of PV on Mars will be much cheaper at utility scale. There is no land cost and the lack of adverse weather on Mars means that PV panels don't need to be laboriously fixed into strong frames.



Calliban wrote:

Like I said before, the 2¢/kWh is the cost after subsidy, hidden or otherwise.  It is not representative of the real cost of electricity.

https://wryheat.wordpress.com/2015/08/0 … skyrocket/

Mars needs cheap electricity.  Basic living space and agricultural land must be encased in a pressurised shell of steel, which is reduced from ore using electrolytic hydrogen.  Water must be mined from the ground using as much energy as it takes to make concrete on Earth.  This is not something that can be done with solar panels.


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#24 2019-11-05 10:45:12

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 519

Re: Low-cost nuclear reactors

China produced 23% more electricity from nuclear power, 253.53TWh, between January and September than in the same period last year, according to figures released by the China Nuclear Energy Association.  This represents 4.8% of China's total power generation during the first three quarters of 2019.

https://wna.informz.ca/informzdataservi … IyMDY2MTg4

China's nuclear generating capacity is growing at a rapid pace of 18.6% growth per year (in 2018).  If that growth rate continues for another decade, the Chinese will be generating about a quarter of their present electricity consumption from nuclear energy and will have around 3 times as much nuclear generating capacity as France.

Do you suppose these people know something that we don't?


Interested in space science, engineering and technology.

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#25 2019-11-05 14:32:17

louis
Member
From: UK
Registered: 2008-03-24
Posts: 5,868

Re: Low-cost nuclear reactors

Do they know something we don't? Yep...if you use free prison labour to build nuclear reactors you can build them more cheaply...

Seriously, take a look at this projection from BP:

https://www.bp.com/content/dam/bp/busin … -china.pdf

The analysis states "Nuclear increases by 7.3% p.a. from 2017 to 2040, and China accounts for 37% of global nuclear power generation in 2040. Renewables expand rapidly, rising by8.5% p.a. to 2040, and accounting for 26% of global renewables by then" - so renewables are growing at a faster rate than nuclear. Do you think that means they know something else?

China is a great big galumphing Communist-led state. The only reason it's been so successful is because, beginning with Nixon and Kissinger's misguided policy, we allowed them to steal our technology and combine it with their cheap labour (kept cheap by political oppression) and racketeer capitalism to undertake a Long March through our markets. Crazy!

But I don't think they are that nimble on their feet. PV technology in particular is a radical new technology that could see incredible leaps in performance. The USA will be in a much better position than China, the UK or Europe to respond very quickly and apply new technology to their electricity generation.

Calliban wrote:

China produced 23% more electricity from nuclear power, 253.53TWh, between January and September than in the same period last year, according to figures released by the China Nuclear Energy Association.  This represents 4.8% of China's total power generation during the first three quarters of 2019.

https://wna.informz.ca/informzdataservi … IyMDY2MTg4

China's nuclear generating capacity is growing at a rapid pace of 18.6% growth per year (in 2018).  If that growth rate continues for another decade, the Chinese will be generating about a quarter of their present electricity consumption from nuclear energy and will have around 3 times as much nuclear generating capacity as France.

Do you suppose these people know something that we don't?


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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