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#1 2017-06-13 11:05:27

Antius
Member
From: Cumbria, UK
Registered: 2007-05-22
Posts: 1,003

Magnox Nuclear Reactors for Mars

Well into the base building phase on Mars, the most practicable option for power supply on a Mars base will be nuclear reactors and solar power systems imported from Earth.  However, as base population increases beyond 1000 and the scope of local ISRU increases, the increasing mass requirements of the power supply will become increasingly burdensome.  A Mars colony will need large quantities of power to mine resources, reduce metal ores, manufacture machinery and other goods, new living space and propellant.  Heating loads on Mars will be at least equal to those of colder regions on Earth and greenhouses must be heated to prevent frost damage to food crops at night.

Whilst solar power systems will provide energy in niche applications, the limited EROI and low energy density of these systems will make them relatively expensive and living on Mars will be energy intensive, as most products, food and living space must be manufactured locally.  For this reason, high living standards and high growth rates can be sustained only by using nuclear reactors.

The options for nuclear power development at colony phase are either to (1). Import high-enrichment, high power density reactor cores from Earth and build secondary systems on Mars; (2) Attempt to enrich uranium on Mars and build high power density cores; (3) Build natural uranium reactors on Mars.

The first involves a large import bill, although the energy density of enriched uranium is extremely high.  At 10% burn-up, it comes to 30GW-days per tonne.

The second would involve centrifuge enrichment of uranium hexaflouride, which would appear impractical for a small colony.  On Earth, the smallest nations to attempt this have populations of several million people.

The third would involve natural uranium reactors, using natural uranium mined from ores on Mars.  This would appear to be the only intermediate term option to direct import of nuclear fuel.  Candu reactors fission natural uranium using a deuterium moderator.  However, deuterium enrichment would appear almost as capital intensive as uranium enrichment.  The other option is graphite moderated reactors, with a low cross-section cladding (Magnox).  These have the advantage that graphite is easily manufactured on Mars and the reactors are quite easy to build.  The UK began construction of its first magnox in 1953 and completed it in just 3 years.  However, power density is low compared to light water reactors.

https://en.m.wikipedia.org/wiki/Magnox

The minimum critical diameter for a magnox reactor was calculated as being 26 feet, but this would generate negligible power.  Calder hall was the first UK power reactor, with a diameter of 36' and a power output of 50MWe (182MWth).  The core contains 120 tonnes of natural U and 1140 tonnes of graphite.

US per capita electricity consumption is 12MWh per capita per year.  Assuming a Mars colony consumes energy at the same rate, a magnox reactor with power output 50MWe would provide enough power for a colony of 36,000 people.  The waste heat from the reactor would be sufficient to heat 450,000m2 of greenhouses to a temperature of 300K around the clock.  On this basis, we might begin building such a reactor when base population reaches several thousand.

Last edited by Antius (2017-06-13 12:47:37)

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#2 2017-06-13 11:19:10

Oldfart1939
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Registered: 2016-11-26
Posts: 2,306

Re: Magnox Nuclear Reactors for Mars

If this is the Mars Nuclear thread, I'm on board. Not that I particularly like radioactive waste products, but the energy is highly efficient--especially once we shift to Thorium based reactors.

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#3 2017-06-13 11:45:15

Terraformer
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From: Ceres
Registered: 2007-08-27
Posts: 3,560
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Re: Magnox Nuclear Reactors for Mars

Would deuterium enrichment be that expensive? Martian water is already significantly enriched in it, and the mass difference between deuterium and protium is far greater than that between isotopes of uranium.

Once we have hundreds of people on Mars, I think options like water-based (or salt based?) heat storage for solar energy will become feasible to build. So would Nickel Iron batteries. I think solar will become a more viable option then, though perhaps not PV, it depends on how difficult it is to manufacture.


"I'm gonna die surrounded by the biggest idiots in the galaxy." - If this forum was a Mars Colony

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#4 2017-06-13 12:38:41

Antius
Member
From: Cumbria, UK
Registered: 2007-05-22
Posts: 1,003

Re: Magnox Nuclear Reactors for Mars

Here is a detailed description of the Magnox type reactor.

http://www.iaea.org/inis/collection/NCL … 052480.pdf

The French developed a similar reactor - the Natural Uranium Gas Graphite (NUGG) reactor.

Whether it would be easier to enrich deuterium on Mars and develop a pressure tube reactor, is something worth discussing.  I do know that heavy water has a slightly higher boiling point than normal water.  It may be possible to use nuclear waste heat to enrich it using a cascade of boilers and condensers.  Maybe this could be done at a small scale.

Last edited by Antius (2017-06-13 12:44:24)

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#5 2017-06-14 04:32:06

louis
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From: UK
Registered: 2008-03-24
Posts: 7,208

Re: Magnox Nuclear Reactors for Mars

It's quite clear unsubsidised solar is already beating nuclear on price:

https://en.wikipedia.org/wiki/Cost_of_e … lectricity

Nuclear now costs around $95-105 per MWh, solar can at its best come in at 40% less. Is the price of nuclear going to go down? No. Is the price of solar going to continue to go down? Yes - substantially, as all experts agree.

Why is nuclear so expensive when its EROI is so good? Easy - you don't include the energy requirements of human beings in your EROI calculations. Nuclear power - building, maintaining, and maintaining is horribly labour intensive, and therefore costly.

Antius wrote:

Here is a detailed description of the Magnox type reactor.

http://www.iaea.org/inis/collection/NCL … 052480.pdf

The French developed a similar reactor - the Natural Uranium Gas Graphite (NUGG) reactor.

Whether it would be easier to enrich deuterium on Mars and develop a pressure tube reactor, is something worth discussing.  I do know that heavy water has a slightly higher boiling point than normal water.  It may be possible to use nuclear waste heat to enrich it using a cascade of boilers and condensers.  Maybe this could be done at a small scale.


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

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#6 2017-06-14 04:37:38

elderflower
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Registered: 2016-06-19
Posts: 1,262

Re: Magnox Nuclear Reactors for Mars

Magnox had problems with corrosion and with dimensional instability of the graphite blocks. These have been overcome, but the development from them, called AGR, proved excessively expensive so only a couple were built.
All graphite moderated reactors that I know of, suffer from the potential to catch fire, as they did at Winscale and Chernobyl. C+H2O=CO +H2 or C+CO2=2CO depending whether water/steam cooled or CO2 gas cooled.
The usual method of extracting heavy water on earth is by electrolysis. Since a Mars colony will be extracting water and electrolysing it in fairly large amounts, heavy water will be a by-product. Mars water has a much higher concentration of HDO than has earth water. This makes Heavy water moderated fission reactors quite attractive as it is the cost of the large reservoir of heavy water that makes them difficult to justify economically on Earth .
If fusion should become a practical option for either rocketry or power production a supply of Deuterium and Tritium (which is produced in a heavy water moderated reactor) will be needed.
I have posted about this stuff previously- somewhere on this site.

Last edited by elderflower (2017-06-14 04:39:10)

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#7 2017-06-14 07:28:55

Antius
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From: Cumbria, UK
Registered: 2007-05-22
Posts: 1,003

Re: Magnox Nuclear Reactors for Mars

Louis is correct in this case.  The EROI of nuclear energy in most parts the western world may be lower than calculations would suggest, because of the labour required to implement safety management at all stages of a nuclear project.  People and their lifestyle energy consumption needs to be part of an EROI calculation if those people are working on what is being examined.

Nuclear energy can be very cheap or very expensive.  It all depends upon the adequacy of the design, the build time of the reactors and the regulatory regime.  It is always easy to push up the cost of a new project, by adding additional requirements.

Euan Mearns wrote an excellent article for Oil Price magazine on the cost trends for new nuclear reactors and the causes of recent price increases.

http://oilprice.com/Alternative-Energy/ … Power.html

Also, the article he references appears to be open access, for those that are interested:

http://www.sciencedirect.com/science/ar … 1516300106

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#8 2017-06-14 08:35:09

RobS
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From: South Bend, IN
Registered: 2002-01-15
Posts: 1,701
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Re: Magnox Nuclear Reactors for Mars

Even though Mars is colder than Earth, I gather experts in settlement construction are concerned about eliminating excess heat. A greenhouse will be receiving nearly half a kilowatt of sunlight per square meter all day; that's a lot of heat. So I don't think greenhouses will need to be heated, nor will living areas.

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#9 2017-06-14 09:04:25

Antius
Member
From: Cumbria, UK
Registered: 2007-05-22
Posts: 1,003

Re: Magnox Nuclear Reactors for Mars

RobS wrote:

Even though Mars is colder than Earth, I gather experts in settlement construction are concerned about eliminating excess heat. A greenhouse will be receiving nearly half a kilowatt of sunlight per square meter all day; that's a lot of heat. So I don't think greenhouses will need to be heated, nor will living areas.

For a settlement buried underground that would certainly be true.  Also, ordinary Martian regolith at 6mbar pressure, is about as insulative as rock wool here on Earth.

Greenhouses at night are a different matter.  A greenhouse at a temperature of 288K (15C) will radiate heat into the Martian sky at a rate of 390W/m2.  It is doing that 24 hours per day.  During the day, it will gain an average of about 300W/m2 for the 12 hours that the sun is about the horizon.  So, it will require heating about 75% of the time if it is to remain warm around the clock.  The heat load may be reduced by using a reflective cover at night and at times when the sun is low on the horizon, but it is difficult to see how the greenhouse could remain above freezing without some heating.

Last edited by Antius (2017-06-14 09:06:11)

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#10 2017-06-14 09:32:10

Antius
Member
From: Cumbria, UK
Registered: 2007-05-22
Posts: 1,003

Re: Magnox Nuclear Reactors for Mars

According to this site, the Candu heavy water reactor core has a power density of 11MWth/m3.

http://www.nuceng.ca/candu/

This compares to about 0.5MW/m3 for Magnox.  So a heavy water reactor core would definitely be smaller for the same amount of power.  This is largely due to the much better moderating power of heavy water compared to carbon.

In terms of thermal efficiency, they are about the same.  A Candu is more difficult from a materials viewpoint, as we need heavy water for the moderator, zircaloy for the pressure tubes and fuel cladding and stainless steel for primary circuit pipework and steam generators.

For a Magnox, we need carbon steel for the boilers, diagrid, and the stressing tendons, a lot of pure graphite for moderator, concrete for the pressure vessel and magnesium alloy for the cladding.  Magnox is technically easier, but the core is much larger.

Last edited by Antius (2017-06-14 09:41:52)

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#11 2017-06-14 10:03:46

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,343
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Re: Magnox Nuclear Reactors for Mars

Post moved. Responding to greenhouse energy.
Designing the best greenhouse demonstrator for Mars

Last edited by RobertDyck (2017-06-14 10:13:57)

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#12 2017-06-14 11:37:43

kbd512
Administrator
Registered: 2015-01-02
Posts: 6,228

Re: Magnox Nuclear Reactors for Mars

Louis,

The only reason any other form of utility electric power generation can beat nuclear power on cost is the fact that governments subsidize the hell out of "renewables" and then don't call it what it actually is.  "Renewables" is a misnomer of epic proportions since solar panels and wind turbines degrade with age and have to be replaced.  Nuclear fuel can be utilized indefinitely, even though fuel requires an investment in reprocessing.  That's what I consider "renewable".  When we put spent fuel in the reactor with new fuel, we get more fuel.  We can only "run out of fuel" by choice.

Edit: This was the part of my post that was "wrong".  Apparently we're already getting more power from nuclear than all "renewables" combined.  Some power from nuclear is sold to electric utility providers and some is not.

To provide some idea of just how lopsided electric power generation in Texas is between nuclear and "renewables", just 2 nuclear power plants in Texas operating 4 reactors between them provide more than half as much electrical power every year as 27 solar and wind generating stations spread across the state.  Power plant nameplate capacity vs actual production means nothing.  The land use associated with nuclear power is barely worth mentioning compared to solar and wind.  If construction on the other 4 reactors at the same 2 sites moved forward, you'd get more power from 2 power plants than all the "renewables" combined.

PV power is highly subsidized here in the US and here in Texas.  Robbing Peter to pay Paul is the only reason why it's competitive with any other form of utility electrical power generation.  Even at that, the cost remains higher here in the US and enormous solar power generating stations still require coal or gas power generating stations to provide power when the Sun doesn't shine and the wind doesn't blow.

The total output power and costs associated with solar and wind power plants are a sick joke compared to what nuclear produces.  The overwhelming majority of our electrical power comes from coal or gas because so-called environmentalists can't accept the fact that even absurdly inefficient use of nuclear power crushes all competitors in terms of power extracted per pound of waste produced.

The very first time Liquid Fluoride Thorium Reactors are mass produced on an assembly line, all nonsense about how cost competitive other competing forms of electric power generation could be will cease.  In terms of land use, natural resource use, and total cost of operations, no other forms of electric power generation are as competitive.  Molten Salt Solar Reactors are a distant second, but still feasible on the scale required and don't come with the red tape of nuclear power generation.

I don't care about whether or not people power their homes with PV panels or office buildings, but there should be no robbing of Peter to do that.  There's no associated land use and since the roof is going to get baked by the Sun anyway, it may as well have PV panels on top of it to get some power.

Last edited by kbd512 (2017-06-15 12:32:23)

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#13 2017-06-14 14:41:18

louis
Member
From: UK
Registered: 2008-03-24
Posts: 7,208

Re: Magnox Nuclear Reactors for Mars

I don't think you followed up my link. The comparisons relate to levelised unsubsidised cost.

I am not too fond of the "renewables" label either since nothing is "renewed" (basically the sun is slowly dying).  I would probably call them Universal Energy - things that just about all countries can utilise within their own borders, be it solar, wind, geothermal, energy from waste, bioenergy etc.

Texas? Take a look at this link:

https://www.eia.gov/state/analysis.php?sid=TX

Half of the electricity generated in Texas in 2015 came from natural gas-fired power plants. Coal-fired power plants historically accounted for about one-third of net electricity generation, but, in 2015, with older coal plants reducing operations or closing, coal supplied about one-fourth of generation.Two nuclear plants supply nearly one-tenth of the state's net electricity generation, and the rest is powered by renewable resources, primarily wind.  

By my calculation that means nuclear provided 10% and renewables provided 15% - 50% more.

Look at the direction of travel across the planet and it's all towards renewables, not surprisingly as the price of wind and especially solar has been reducing so markedly.


kbd512 wrote:

Louis,

The only reason any other form of utility electric power generation can beat nuclear power on cost is the fact that governments subsidize the hell out of "renewables" and then don't call it what it actually is.  "Renewables" is a misnomer of epic proportions since solar panels and wind turbines degrade with age and have to be replaced.  Nuclear fuel can be utilized indefinitely, even though fuel requires an investment in reprocessing.  That's what I consider "renewable".  When we put spent fuel in the reactor with new fuel, we get more fuel.  We can only "run out of fuel" by choice.

To provide some idea of just how lopsided electric power generation in Texas is between nuclear and "renewables", just 2 nuclear power plants in Texas operating 4 reactors between them provide more than half as much electrical power every year as 27 solar and wind generating stations spread across the state.  Power plant nameplate capacity vs actual production means nothing.  The land use associated with nuclear power is barely worth mentioning compared to solar and wind.  If construction on the other 4 reactors at the same 2 sites moved forward, you'd get more power from 2 power plants than all the "renewables" combined.

PV power is highly subsidized here in the US and here in Texas.  Robbing Peter to pay Paul is the only reason why it's competitive with any other form of utility electrical power generation.  Even at that, the cost remains higher here in the US and enormous solar power generating stations still require coal or gas power generating stations to provide power when the Sun doesn't shine and the wind doesn't blow.

The total output power and costs associated with solar and wind power plants are a sick joke compared to what nuclear produces.  The overwhelming majority of our electrical power comes from coal or gas because so-called environmentalists can't accept the fact that even absurdly inefficient use of nuclear power crushes all competitors in terms of power extracted per pound of waste produced.

The very first time Liquid Fluoride Thorium Reactors are mass produced on an assembly line, all nonsense about how cost competitive other competing forms of electric power generation could be will cease.  In terms of land use, natural resource use, and total cost of operations, no other forms of electric power generation are as competitive.  Molten Salt Solar Reactors are a distant second, but still feasible on the scale required and don't come with the red tape of nuclear power generation.

I don't care about whether or not people power their homes with PV panels or office buildings, but there should be no robbing of Peter to do that.  There's no associated land use and since the roof is going to get baked by the Sun anyway, it may as well have PV panels on top of it to get some power.

Last edited by louis (2017-06-14 14:42:08)


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

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#14 2017-06-14 15:59:14

elderflower
Member
Registered: 2016-06-19
Posts: 1,262

Re: Magnox Nuclear Reactors for Mars

CANDU reactor design has been reworked considerably by India, with a view to using a lot of Thorium as fuel. The Indian developments must be considered in assessing the capabilities of Heavy Water moderated reactors.

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#15 2017-06-14 18:57:21

kbd512
Administrator
Registered: 2015-01-02
Posts: 6,228

Re: Magnox Nuclear Reactors for Mars

louis wrote:

I don't think you followed up my link. The comparisons relate to levelised unsubsidised cost.

Louis,

There is no such thing as unsubsidized solar power in Texas.  I live here.  It's all subsidized by Uncle Sam.  It's even part of how it's advertised to consumers.  I looked into purchase of PV panels for my home.  If you buy solar panels, Uncle Sam gives you a tax break.  Robbing Peter to pay Paul is the dictionary definition of a "subsidy".

Most of the time, Peter wouldn't buy PV panels that may or may not pay off in 20 years unless Paul was helping to foot the bill.  This is the little game the "renewables" advocates like to play.  As long as they're spending someone else's money and putting a power plant on someone else's land, they don't care how much it costs or how much land is required.  Why do you think we still use so much petroleum products and coal?  Even with highway robbery, the output is still a joke.

louis wrote:

I am not too fond of the "renewables" label either since nothing is "renewed" (basically the sun is slowly dying).  I would probably call them Universal Energy - things that just about all countries can utilise within their own borders, be it solar, wind, geothermal, energy from waste, bioenergy etc.

I agree that "renewables" is not the right label.  I think expensive poor-output waste of money is more appropriate terminology.

louis wrote:

Texas? Take a look at this link: https://www.eia.gov/state/analysis.php?sid=TX

My last post about nuclear and renewables was completely wrong because I didn't bother to read the chart from the website you and I both visited.  Apparently you didn't, either.  Nuclear still produces more power than all renewables combined.  If Texas built the 4 new reactors already approved by DOE, 2 at Comanche Peak and 2 at Matagorda, the money wasted on renewables would've produced double the amount of power already produced by nuclear without substantially increasing the geographic footprint of our existing nuclear generating stations.

louis wrote:

Half of the electricity generated in Texas in 2015 came from natural gas-fired power plants. Coal-fired power plants historically accounted for about one-third of net electricity generation, but, in 2015, with older coal plants reducing operations or closing, coal supplied about one-fourth of generation.Two nuclear plants supply nearly one-tenth of the state's net electricity generation, and the rest is powered by renewable resources, primarily wind.

By my calculation that means nuclear provided 10% and renewables provided 15% - 50% more.

Take a look at this link from the same website that you referenced above that shows total output by source:

Table 1.1. Total Electric Power Industry Summary Statistics, 2015 and 2014

The figures on the left hand side of the table in the link I referenced above represent total generation by source for 2015 and 2014.  The figures shown below are total output, for nuclear and renewables, for January 1, 2015 to December 31, 2015, for the State of Texas:

Nuclear: 797,178MWh
Hydroelectric: 249,080MWh
Renewable Sources (Wind, PV, solar thermal, wood, biomass, geothermal) Excluding Hydroelectric: 295,161MWh

Nuclear Total: 797,178MWh
Renewables Total: 544,241MWh

louis wrote:

Look at the direction of travel across the planet and it's all towards renewables, not surprisingly as the price of wind and especially solar has been reducing so markedly.

If the direction of everyone across the planet is moving towards solutions that don't work, then maybe I need to open the KBD School for Kids Who Can't Count Good and Want to Do Other Stuff Good Too in order to combat this counting problem.

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#16 2017-06-14 19:07:51

louis
Member
From: UK
Registered: 2008-03-24
Posts: 7,208

Re: Magnox Nuclear Reactors for Mars

I think you are confusing your experience with the analyses I linked to. The whole point about levelised cost is that you subtract any subsidies. Levelised cost means you try and reconcile capital and revenue expenditure. You simply don't address the fact that wind and solar are, in some cases,  now beating all other energy systems in open bids without subsidies. 

Ha-ha I still prefer the Universal Energy label!

You disprove my Jan 2017 report on electricity generation for Texas by referring to 2015 figures?  Hmmm....


kbd512 wrote:
louis wrote:

I don't think you followed up my link. The comparisons relate to levelised unsubsidised cost.

Louis,

There is no such thing as unsubsidized solar power in Texas.  I live here.  It's all subsidized by Uncle Sam.  It's even part of how it's advertised to consumers.  I looked into purchase of PV panels for my home.  If you buy solar panels, Uncle Sam gives you a tax break.  Robbing Peter to pay Paul is the dictionary definition of a "subsidy".

Most of the time, Peter wouldn't buy PV panels that may or may not pay off in 20 years unless Paul was helping to foot the bill.  This is the little game the "renewables" advocates like to play.  As long as they're spending someone else's money and putting a power plant on someone else's land, they don't care how much it costs or how much land is required.  Why do you think we still use so much petroleum products and coal?  Even with highway robbery, the output is still a joke.

louis wrote:

I am not too fond of the "renewables" label either since nothing is "renewed" (basically the sun is slowly dying).  I would probably call them Universal Energy - things that just about all countries can utilise within their own borders, be it solar, wind, geothermal, energy from waste, bioenergy etc.

I agree that "renewables" is not the right label.  I think expensive poor-output waste of money is more appropriate terminology.

louis wrote:

Texas? Take a look at this link: https://www.eia.gov/state/analysis.php?sid=TX

My last post about nuclear and renewables was completely wrong because I didn't bother to read the chart from the website you and I both visited.  Apparently you didn't, either.  Nuclear still produces more power than all renewables combined.  If Texas built the 4 new reactors already approved by DOE, 2 at Comanche Peak and 2 at Matagorda, the money wasted on renewables would've produced double the amount of power already produced by nuclear without substantially increasing the geographic footprint of our existing nuclear generating stations.

louis wrote:

Half of the electricity generated in Texas in 2015 came from natural gas-fired power plants. Coal-fired power plants historically accounted for about one-third of net electricity generation, but, in 2015, with older coal plants reducing operations or closing, coal supplied about one-fourth of generation.Two nuclear plants supply nearly one-tenth of the state's net electricity generation, and the rest is powered by renewable resources, primarily wind.

By my calculation that means nuclear provided 10% and renewables provided 15% - 50% more.

Take a look at this link from the same website that you referenced above that shows total output by source:

Table 1.1. Total Electric Power Industry Summary Statistics, 2015 and 2014

The figures on the left hand side of the table in the link I referenced above represent total generation by source for 2015 and 2014.  The figures shown below are total output, for nuclear and renewables, for January 1, 2015 to December 31, 2015, for the State of Texas:

Nuclear: 797,178MWh
Hydroelectric: 249,080MWh
Renewable Sources (Wind, PV, solar thermal, wood, biomass, geothermal) Excluding Hydroelectric: 295,161MWh

Nuclear Total: 797,178MWh
Renewables Total: 544,241MWh

louis wrote:

Look at the direction of travel across the planet and it's all towards renewables, not surprisingly as the price of wind and especially solar has been reducing so markedly.

If the direction of everyone across the planet is moving towards solutions that don't work, then maybe I need to open the KBD School for Kids Who Can't Count Good and Want to Do Other Stuff Good Too in order to combat this counting problem.


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

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#17 2017-06-15 05:16:07

Antius
Member
From: Cumbria, UK
Registered: 2007-05-22
Posts: 1,003

Re: Magnox Nuclear Reactors for Mars

The problem is that we are comparing apples to oranges.  Dispatchable electricity from a coal or nuclear power plant is not the same product as variable, intermittent energy from a wind or solar power plant.  In order for intermittent renewable energy to do the same job as dispatchable energy, it must be backed up by a conventional power plant and excess power at peak times must be exported, stored or wasted in a dump load.  Without back-up and storage, energy production will not meet demand.  If that doesn’t happen, the result is frequency transients that will crash the entire grid.

The renewable energy basically gets dumped onto the grid when it is available.  Conventional power plants must then cut back production, losing market share, and then ramp up production when renewable electricity falls off load.  The power plant must sit there, fully manned and in hot standby, essentially waiting – whilst unpaid capital, maintenance and labour costs stack up.  The only economic benefit that renewable energy sources provide is to save fuel in the back-up power plants.  For high renewable penetration you would need storage as well.  So we need three power plants instead of just one.  Germany provides a cautionary example that we should think twice before attempting to follow:

http://www.telegraph.co.uk/finance/news … onomy.html

http://www.theenergycollective.com/will … ys-economy

A large chunk of renewable energy production in Germany is hydropower, something that has been in place for a very long time.  Hydropower is able to compete with fossil and nuclear because it does not suffer from the same disadvantages as intermittent renewables.  It is relatively power dense and is highly controllable (dispatchable).  It is no surprise then that it is already maxed out in most countries, with little opportunity for further expansion.  If we had the ability to ramp up hydropower, no one would bother with intermittent renewable energy sources.

Establishing new coal and nuclear power, faces some severe hurdles in developed countries.  For one thing, very little of either type of power plant has been constructed in the western world for the past 25 years.  Most new power plants have been natural-gas combined cycle gas-turbine plants.  The expertise and workforce needed to construct large steam plants no longer exists in most western countries.  Deindustrialisation has robbed us of the capability.  To get the sort of low cost electricity from nuclear power as is seen in countries like France, large scale economies are needed in the production of identical units.  On top of that, any nuclear project in the US or UK is basically strangled by a regulatory regime that stretches out build times, which ramps up capital costs.

Comparing a large-scale PV solar against new nuclear in levelised cost studies, will therefore tend to make solar look a lot cheaper than it really is (i.e. back-up and storage costs are rarely included) and nuclear a lot more expensive than it really needs to be (real costs will depend upon the capability of the workforce, scale effects and the regulatory regime).

Of course, there is no coal or natural gas on Mars, at least not that we know of and no oxygen to burn them even if they do exist.  The wind carries 100 times less energy.  The sun is 2.3 times weaker.  Water is frozen as hard as stone, so prospects for hydropower are not promising.  Biomass means growing things in greenhouses that you need to burn instead of eating.  If these things don’t work well on Earth, how well do you think they will work on Mars?

Nuclear power on the other hand is likely to be more efficient on Mars.  Heat sink temperatures are lower, boosting Carnot efficiency and I doubt that there will be any such thing as ‘waste heat’ on Mars.  The only question in my mind is whether a Martian economy should import its reactor or build them from local resources.  I raised the prospect of Magnox because it is something that can be built at a relatively low level of industrialisation - no enrichment is needed and components are relatively simple and can be made from low grade materials such as plain carbon steel, graphite and magnesium-aluminium alloys.  On the downside, these reactors are inherently large, low power density and have reduced thermal efficiency compared to other more advanced technologies.  But if someone were to ask me to build a nuclear reactor with limited materials and manufacturing capability, this is the way I would go.  If I had enrichment capabilities, heavy water, zirconium, stainless steels and reprocessing plants, the answer would be different.

Last edited by Antius (2017-06-15 05:38:07)

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#18 2017-06-15 06:05:44

louis
Member
From: UK
Registered: 2008-03-24
Posts: 7,208

Re: Magnox Nuclear Reactors for Mars

The intermittency issue is a fair one to raise. It clearly can be disruptive. That is more of an issue with wind than solar, which is more dependable within in a range. The intermittency issue has not yet been solved but that doesn't mean it won't be. There was a time when solar was hugely more expensive than nuclear. That is no longer the case. I think storage will go the same way. There are many potential technical solutions to the storage issue. Eventually one will take the lead and be fine tuned, till combined with solar it becomes competitive.

In terms of energy on Mars, though, a wide range of different considerations apply.

If we are talking about a small colony of say up to 1000, I don't think there is any prospect of them building their own nuclear reactors. That means you are condemning the settlers to continue importing tonnes of energy equipment from Earth.  Having looked into it, I see no reason why with imported 3D printers, purification machinery, glass and other manufacturing capability, that the settlers shouldn't be able to produce their own PV panels on Mars from ISRU materials like silicon. They can easily make their own chemcial batteries as well.

Regarding nuclear, if you do have a radioactive leak, isn't it way more dangerous in the dusty Mars atmosphere - not being washed away by rain?

I also think nuclear power is too labour intensive.  The PV panel manufacturing process on Mars can be largely automated and once deployed, the panels can more or less be forgotten. Robot vehicles can give automatically blow away dust off the panels.

Even if we continue to import PV panels, it is much easier to stow those in rockets rather than nuclear power plants.



Antius wrote:

The problem is that we are comparing apples to oranges.  Dispatchable electricity from a coal or nuclear power plant is not the same product as variable, intermittent energy from a wind or solar power plant.  In order for intermittent renewable energy to do the same job as dispatchable energy, it must be backed up by a conventional power plant and excess power at peak times must be exported, stored or wasted in a dump load.  Without back-up and storage, energy production will not meet demand.  If that doesn’t happen, the result is frequency transients that will crash the entire grid.

The renewable energy basically gets dumped onto the grid when it is available.  Conventional power plants must then cut back production, losing market share, and then ramp up production when renewable electricity falls off load.  The power plant must sit there, fully manned and in hot standby, essentially waiting – whilst unpaid capital, maintenance and labour costs stack up.  The only economic benefit that renewable energy sources provide is to save fuel in the back-up power plants.  For high renewable penetration you would need storage as well.  So we need three power plants instead of just one.  Germany provides a cautionary example that we should think twice before attempting to follow:

http://www.telegraph.co.uk/finance/news … onomy.html

http://www.theenergycollective.com/will … ys-economy

A large chunk of renewable energy production in Germany is hydropower, something that has been in place for a very long time.  Hydropower is able to compete with fossil and nuclear because it does not suffer from the same disadvantages as intermittent renewables.  It is relatively power dense and is highly controllable (dispatchable).  It is no surprise then that it is already maxed out in most countries, with little opportunity for further expansion.  If we had the ability to ramp up hydropower, no one would bother with intermittent renewable energy sources.

Establishing new coal and nuclear power, faces some severe hurdles in developed countries.  For one thing, very little of either type of power plant has been constructed in the western world for the past 25 years.  Most new power plants have been natural-gas combined cycle gas-turbine plants.  The expertise and workforce needed to construct large steam plants no longer exists in most western countries.  Deindustrialisation has robbed us of the capability.  To get the sort of low cost electricity from nuclear power as is seen in countries like France, large scale economies are needed in the production of identical units.  On top of that, any nuclear project in the US or UK is basically strangled by a regulatory regime that stretches out build times, which ramps up capital costs.

Comparing a large-scale PV solar against new nuclear in levelised cost studies, will therefore tend to make solar look a lot cheaper than it really is (i.e. back-up and storage costs are rarely included) and nuclear a lot more expensive than it really needs to be (real costs will depend upon the capability of the workforce, scale effects and the regulatory regime).

Of course, there is no coal or natural gas on Mars, at least not that we know of and no oxygen to burn them even if they do exist.  The wind carries 100 times less energy.  The sun is 2.3 times weaker.  Water is frozen as hard as stone, so prospects for hydropower are not promising.  Biomass means growing things in greenhouses that you need to burn instead of eating.  If these things don’t work well on Earth, how well do you think they will work on Mars?

Nuclear power on the other hand is likely to be more efficient on Mars.  Heat sink temperatures are lower, boosting Carnot efficiency and I doubt that there will be any such thing as ‘waste heat’ on Mars.  The only question in my mind is whether a Martian economy should import its reactor or build them from local resources.  I raised the prospect of Magnox because it is something that can be built at a relatively low level of industrialisation - no enrichment is needed and components are relatively simple and can be made from low grade materials such as plain carbon steel, graphite and magnesium-aluminium alloys.  On the downside, these reactors are inherently large, low power density and have reduced thermal efficiency compared to other more advanced technologies.  But if someone were to ask me to build a nuclear reactor with limited materials and manufacturing capability, this is the way I would go.  If I had enrichment capabilities, heavy water, zirconium, stainless steels and reprocessing plants, the answer would be different.


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

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#19 2017-06-15 08:54:08

kbd512
Administrator
Registered: 2015-01-02
Posts: 6,228

Re: Magnox Nuclear Reactors for Mars

louis wrote:

I think you are confusing your experience with the analyses I linked to. The whole point about levelised cost is that you subtract any subsidies. Levelised cost means you try and reconcile capital and revenue expenditure. You simply don't address the fact that wind and solar are, in some cases,  now beating all other energy systems in open bids without subsidies.

If there ever was such a thing, maybe your claim would have merit.  Since there never has been, your claim does not have merit.

louis wrote:

You disprove my Jan 2017 report on electricity generation for Texas by referring to 2015 figures?  Hmmm....

The report you referenced was written AFTER the data from 2015 was collated.  Do you realize that the part of the report you quoted makes specific reference to 2015 data?  The figures I provided were from tables that contain 2015 and 2014 data.  Looking at output sent to utility providers instead of both utility providers and IPP's or NUG's does not indicate what the total output was for a given calendar year.

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#20 2017-06-15 11:22:58

Antius
Member
From: Cumbria, UK
Registered: 2007-05-22
Posts: 1,003

Re: Magnox Nuclear Reactors for Mars

louis wrote:

The intermittency issue is a fair one to raise. It clearly can be disruptive. That is more of an issue with wind than solar, which is more dependable within in a range. The intermittency issue has not yet been solved but that doesn't mean it won't be. There was a time when solar was hugely more expensive than nuclear. That is no longer the case. I think storage will go the same way. There are many potential technical solutions to the storage issue. Eventually one will take the lead and be fine tuned, till combined with solar it becomes competitive.

There have always been solutions to intermittency; they involve storing the intermittent energy in some way and releasing it in a dispatchable way.  The problem is that they are capital intensive and end up eating a large chunk of the energy due to inefficiencies.  So you get hit both ways.  On Mars, the situation is worse in some ways, as you are starting out with only 43% of the sunlight that you get on Earth.  So your solar power system has a 2.3x longer energy payback time.  Adding in storage makes things worse.

I don’t think solar is a good solution for Mars, but here is my best stab at what I think will minimise its disadvantages:

I think it is correct to say that intermittency is less of a problem if it occurs in predictable cycles, but I think the answer lies, if there is one, in low tech solutions.  If solar dynamic power plants are built on Mars, then heat can be stored in cheap materials like rock and used to provide 24/7 power.  That way you at least only have to build one power plant and oversize the collector area to cover 24 hour generation and thermal losses from the store.

The embedded energy in the storage system could be kept relatively small, as materials used can be unprocessed natural materials like rock which need to be corralled around heat transfer pipes, but otherwise not processed in any way.  Because of the near vacuum conditions, ordinary regolith should be a good insulator for a thermal store.  Other ways to get around poor EROI would be to operate at the highest possible temperatures, use high heat capacity and low vapour pressure coolants (liquid metals) in the collectors and use condensing direct cycles for power generation if you can.  The high temperatures push up Carnot efficiency, condensing direct cycles avoid the need for energy invested in heat exchangers, heat exchanger temperature drops and condensing cycles reduce pumping power.  So basically dish type solar collectors, probably using a liquid metal coolant, feeding into a thermal store and direct cycle S-CO2 power cycle drawing energy from the store and then generating electric power.  Use carbon steels where possible and try to avoid thermal transients within the plant.  To maximise the efficiency and EROI of a thermodynamic power plant make it as big as you can.  Also, try and keep the whole thing as compact as possible, so run the S-CO2 generating plant at high pressure.

This is a relatively large scale solution, but dynamic cycles with thermal storage would seem to be the best chance of getting round poor EROI.  If temperatures in the store can get up to 500°C, the efficiency of the power generation cycle might reach 40%.

louis wrote:

In terms of energy on Mars, though, a wide range of different considerations apply.

If we are talking about a small colony of say up to 1000, I don't think there is any prospect of them building their own nuclear reactors. That means you are condemning the settlers to continue importing tonnes of energy equipment from Earth.  Having looked into it, I see no reason why with imported 3D printers, purification machinery, glass and other manufacturing capability, that the settlers shouldn't be able to produce their own PV panels on Mars from ISRU materials like silicon. They can easily make their own chemcial batteries as well.

We have already discussed Mars-made PV in another thread.  The energy economics are not favourable.  These systems are not energetically favourable here on Earth, which is why Germany is having the problems that it is.  Things are even worse on a planet with less than half the sunlight.  The energy payback time would be several years before you even begin to think about energy storage.

The problem with Mars built Magnox reactors is not their technological sophistication, it is their size.  Anyone that can build a solar thermal power plant has the technological sophistication to build a graphite moderated natural uranium reactor.  The minimum practical heat output of a Magnox reactor is about 150MW.  A Mars colony is unlikely to need something that big until its population is in the thousands.

That said, it is difficult to see why importing a small nuclear reactor from Earth would be burdening the colonists.  If the thermal power plant is manufactured on Mars, then the only thing that needs to be imported is the reactor core and control systems.  For the SP-100 that is about 1100kg for a unit capable of producing 2.5MW of heat.  A larger fast reactor in the tens of MW range would be even more efficient.  One kg of fast reactor fuel taken to 10% burn-up will yield 720,000kWh of heat and 288,000kWh of electric power at 40% conversion efficiency.

louis wrote:

Regarding nuclear, if you do have a radioactive leak, isn't it way more dangerous in the dusty Mars atmosphere - not being washed away by rain?

Possibly.  The source term is the same.  Any release plume would be less buoyant in the Martian atmosphere and would cool and descend more rapidly, but Martian winds could spread radioactive dust a long way.

louis wrote:

I also think nuclear power is too labour intensive.  The PV panel manufacturing process on Mars can be largely automated and once deployed, the panels can more or less be forgotten. Robot vehicles can give automatically blow away dust off the panels.

PV panels are a poor solution, as already discussed.  All thermal power plants require some level of manning, whether they are solar or nuclear.  The power density of a nuclear power plant is higher, so there is good reason to believe manning levels will be comparable or lower.

louis wrote:

Even if we continue to import PV panels, it is much easier to stow those in rockets rather than nuclear power plants.

You really think so? 

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#21 2017-06-15 12:14:48

kbd512
Administrator
Registered: 2015-01-02
Posts: 6,228

Re: Magnox Nuclear Reactors for Mars

Solar Power Advocates,

Louis here has attempted to intimate that what I stated was not applicable to the report he provided a link to because he does not know how to interpret what he read.  This is the prototypical response I receive about solar power when the people making arguments don't know anything about how power is generated, transmitted, or stored, nor how electric power production is tabulated by the government.  If he'd bothered to read the footnotes, which he clearly did not, he would've seen the tables referenced that indicate how electrical power was distributed to commercial electric utility providers versus independent power producers who are not identified as electric utilities but produce and distribute electrical power, nonetheless.  The report referenced 2015 data and I provided the link for the totals and subtotals, which is available on the same website Louis provided a link to, by use sector (commercial electric utility or independent power producer).

These facts are quite relevant to the arguments presented:

Fact #1: The report Louis linked to refers to 2015 output data

Fact #2: I supplied the link to the table that shows total output for 2015 and the breakdown between electric power utility providers and independent power producers

Fact #3: The 2 nuclear generating stations generated more electricity in 2015 than all "renewables" of every kind combined.

Fact #4: Every PV farm requires a gas or coal power plant spewing tens of millions of tons of CO2 and other greenhouse gases into the atmosphere to provide electricity at night because there is no such thing as a grid scale battery and there never has been.  That means that there is no such thing as a battery that stores hundreds of megawatts of power and there never has been in the history of humanity.

Fact #5: Actual 2015 Electrical Power Output from the same Government Website Louis provided the synopsis link to:

All utilities combined produced 4,077,601MWh of electricity
Nuclear produced 797,178MWh of electricity
All renewables combined produced 544,241MWh of electricity

Fact #6: The actual amount of electric power produced from nuclear sources that was sold / delivered to electric utility providers was 416,680MWh, which coincides with the report's claim that 10% of the electric power produced came from nuclear.  400,000Mwh is roughly 10% of 4,000,000MWh.

Fact #7: Anyone who supports use of PV and Wind power without use of utility scale electric power storage, which doesn't exist anywhere in the world and never has, either supports "global warming" / "climate change" or supports nuclear power.  The reason is really simple.  The Sun doesn't shine 24/7 and the wind doesn't blow 24/7.  That means some other power source is required to provide 24/7 electric power.  For whatever reason, the solar and wind advocates are also anti-nuclear, probably because nuclear demonstrates just how superfluous solar, wind, gas, and coal actually are for producing utility grade electric power, therefore gas and coal are the solution of choice when the weather doesn't cooperate.  Heat from nuclear fission is produced 24/7, no matter what the local weather is like.

Fact #8: There are at least 27 solar and wind power plants in Texas and if you combine the total output from all of them (Edit: all of them that are not "hydroelectric", is what I meant), it amounts to less than half of the output from 4 operating nuclear reactors that occupy comparatively tiny parcels of land.

Last edited by kbd512 (2017-06-15 12:17:46)

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#22 2017-06-15 17:31:06

louis
Member
From: UK
Registered: 2008-03-24
Posts: 7,208

Re: Magnox Nuclear Reactors for Mars

Happy to accept I didn't read that document in too much detail but you were making a point about "renewables" in relation to nuclear to begin with. You didn't specifically exclude hydro, biomass etc.

Not all your "facts" are actually facts. Re Fact # 7, Denmark (60% plus electricity generated through Renewables) doesn't have huge energy storage. In terms of putting carbon in the atmosphere, the key figure is the percentage generated from non-carbon fuels. Between 2007 and 2014 they reduced use of fossil fuels by about 50% in relation to electricity generation.

kbd512 wrote:

Solar Power Advocates,

Louis here has attempted to intimate that what I stated was not applicable to the report he provided a link to because he does not know how to interpret what he read.  This is the prototypical response I receive about solar power when the people making arguments don't know anything about how power is generated, transmitted, or stored, nor how electric power production is tabulated by the government.  If he'd bothered to read the footnotes, which he clearly did not, he would've seen the tables referenced that indicate how electrical power was distributed to commercial electric utility providers versus independent power producers who are not identified as electric utilities but produce and distribute electrical power, nonetheless.  The report referenced 2015 data and I provided the link for the totals and subtotals, which is available on the same website Louis provided a link to, by use sector (commercial electric utility or independent power producer).

These facts are quite relevant to the arguments presented:

Fact #1: The report Louis linked to refers to 2015 output data

Fact #2: I supplied the link to the table that shows total output for 2015 and the breakdown between electric power utility providers and independent power producers

Fact #3: The 2 nuclear generating stations generated more electricity in 2015 than all "renewables" of every kind combined.

Fact #4: Every PV farm requires a gas or coal power plant spewing tens of millions of tons of CO2 and other greenhouse gases into the atmosphere to provide electricity at night because there is no such thing as a grid scale battery and there never has been.  That means that there is no such thing as a battery that stores hundreds of megawatts of power and there never has been in the history of humanity.

Fact #5: Actual 2015 Electrical Power Output from the same Government Website Louis provided the synopsis link to:

All utilities combined produced 4,077,601MWh of electricity
Nuclear produced 797,178MWh of electricity
All renewables combined produced 544,241MWh of electricity

Fact #6: The actual amount of electric power produced from nuclear sources that was sold / delivered to electric utility providers was 416,680MWh, which coincides with the report's claim that 10% of the electric power produced came from nuclear.  400,000Mwh is roughly 10% of 4,000,000MWh.

Fact #7: Anyone who supports use of PV and Wind power without use of utility scale electric power storage, which doesn't exist anywhere in the world and never has, either supports "global warming" / "climate change" or supports nuclear power.  The reason is really simple.  The Sun doesn't shine 24/7 and the wind doesn't blow 24/7.  That means some other power source is required to provide 24/7 electric power.  For whatever reason, the solar and wind advocates are also anti-nuclear, probably because nuclear demonstrates just how superfluous solar, wind, gas, and coal actually are for producing utility grade electric power, therefore gas and coal are the solution of choice when the weather doesn't cooperate.  Heat from nuclear fission is produced 24/7, no matter what the local weather is like.

Fact #8: There are at least 27 solar and wind power plants in Texas and if you combine the total output from all of them (Edit: all of them that are not "hydroelectric", is what I meant), it amounts to less than half of the output from 4 operating nuclear reactors that occupy comparatively tiny parcels of land.


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#23 2017-06-15 20:52:26

kbd512
Administrator
Registered: 2015-01-02
Posts: 6,228

Re: Magnox Nuclear Reactors for Mars

louis wrote:

Happy to accept I didn't read that document in too much detail but you were making a point about "renewables" in relation to nuclear to begin with. You didn't specifically exclude hydro, biomass etc.

It's the details that matter, Louis.  Remember that saying "The devil is in the details"?  Well, it applies with full force to every electric power generating solution.

I didn't specifically exclude all other "renewables" because I specifically included those figures in the totals and then said, "Look Louis, 2 nuclear generating stations still produce 250,000MWh more power every year than all renewables of every kind combined, in the State of Texas."

Texas has 4 reactors that occupy pin dot sized parcels of land and don't generate any greenhouse gases and miniscule amounts of waste.  If we built the 4 new reactors authorized for construction by DOE at that pair of nuclear generating stations, output goes up to 1,600,000MWh, minimum.  That would make nuclear power the largest electric generating source in the state by a good wide margin.  If 8 new reactors after built at a 3rd and 4th nuclear generating station, then we can stop using coal.  If another 8 reactors are built at a 5th and 6th nuclear generating station, we can stop using all fossil fuels to generate electric power.

I don't want to shut down any of our solar or wind generating stations.  We should keep all that because we already have it built.  If we're at all serious about pursuing this "global warming" / "climate change" agenda, then the answer is staring everyone in the face and it's not solar or wind or both, it's nuclear.  Nuclear occupies the minimum amount of land and generates the maximum amount of power and no other electric power generating source holds a candle to nuclear power, period, end of story.

louis wrote:

Not all your "facts" are actually facts. Re Fact # 7, Denmark (60% plus electricity generated through Renewables) doesn't have huge energy storage. In terms of putting carbon in the atmosphere, the key figure is the percentage generated from non-carbon fuels. Between 2007 and 2014 they reduced use of fossil fuels by about 50% in relation to electricity generation.

Was it not abundantly clear that we were talking about Texas?

Denmark has a population of a little less than 6 million people.  If you include all the people in the Houston metropolitan area, which is where I live, we have as many people living in a little more than 2/3rds of the land area of Denmark.  Scale and size matter.  Denmark receives nearly 43% of their energy from wind because of where they're situated.  Houston won't get 43% of its energy demands met by wind now, in the next decade, or on any reasonable time scale.  Denmark gets 2% of its power from solar, again, due to local weather.

All of Denmark's renewable power sources generated 28,931GWh in 2015.  Annual output from the 2 reactors at South Texas Nuclear Generating Station is 22,179GWh.  In other words, 2 nuclear reactors operating at 91.7% capacity generated more than 76% as much electric power as all sources in Denmark.  If output from the other 2 nuclear reactors is included, 4 reactors generated more electric power than Denmark uses in a year.  Denmark also consumed 4,865GWh more electric power than it generated in 2015, but that's a minor detail for "renewables" advocates to ignore.

There are no wind or solar generating stations in the US that match the annual output of the average nuclear reactor in the US.  That is not a matter for principle, personal belief, or ideology.  That is cold hard numerology that does not care at all what I or anyone else happen to think or believe.

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#24 2017-06-16 01:49:15

Antius
Member
From: Cumbria, UK
Registered: 2007-05-22
Posts: 1,003

Re: Magnox Nuclear Reactors for Mars

What actually happens is that Denmark generates renewable electricity equivalent to 60% of its consumption, and then dumps it into the electricity grids of Scandinavia and Germany.  It then imports large amounts of electricity power from Scandinavia and Germany at periods of high demand.  It can do that because it is relatively tiny and they are big.  Another interesting but scarcely mentioned fact is that Danish electricity production from other sources is collapsing.  This makes the renewable contribution look bigger, but the reality is that the Danes are importing more.

https://notalotofpeopleknowthat.wordpre … ind-power/

It is theoretically possible to balance the grid internally using flow batteries, thermal storage, CAES, etc.  But at what price?  Denmark already has the highest electricity rates in Europe, followed closely by Germany.  Wealth is basically the use of energy to manipulate matter.  Expensive and scarce energy ultimately translates into less wealth.

Last edited by Antius (2017-06-16 01:49:43)

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#25 2017-06-16 05:35:28

louis
Member
From: UK
Registered: 2008-03-24
Posts: 7,208

Re: Magnox Nuclear Reactors for Mars

I bet Texas's population density is somewhat lower than Denmark's...

As to Texas's suitability for wind energy...

https://www.ecowatch.com/6-reasons-why- … 96525.html

I guess it depends where you are coming from.

For the purposes of this discussion, I am not denying that nuclear energy can produce a lot of energy on a small footprint. But it is also very, very expensive. We are having to guarantee the price of nuclear in the UK for future installations at over

Our next nuclear power station could cost £37 billion for 3.2 GW of electric power. So about £10 billion per GWe.

https://www.theguardian.com/uk-news/201 … up-to-37bn

But what is going to happen to the price of solar power and energy storage over the next three decades? All the signs are that both will continue to fall rapidly.

The issues in relation to Mars are far less about cost and much more to do with suitability, flexibility and reproducibility. My view is that within ten years, a Mars settlement could be producing all its power from ISRU manufacture of PV panels.  It could also store all the power it needs as methane/oxygen, manufacture methane/oxygen generators, and produce chemical batteries in abundance. A 1000 person settlement would have no problem generating say 20 MWs constant using solar as the power source.  That might require say (guesstimate) 2 million sq metres of PV panel. If the settlement can produce panels at a rate of 400 sq metres per day, that means they could produce that many in under 14 years.  Obviously they don't need to achieve that rate immediately.


kbd512 wrote:

louis wrote:

Not all your "facts" are actually facts. Re Fact # 7, Denmark (60% plus electricity generated through Renewables) doesn't have huge energy storage. In terms of putting carbon in the atmosphere, the key figure is the percentage generated from non-carbon fuels. Between 2007 and 2014 they reduced use of fossil fuels by about 50% in relation to electricity generation.

Was it not abundantly clear that we were talking about Texas?

Denmark has a population of a little less than 6 million people.  If you include all the people in the Houston metropolitan area, which is where I live, we have as many people living in a little more than 2/3rds of the land area of Denmark.  Scale and size matter.  Denmark receives nearly 43% of their energy from wind because of where they're situated.  Houston won't get 43% of its energy demands met by wind now, in the next decade, or on any reasonable time scale.  Denmark gets 2% of its power from solar, again, due to local weather.

All of Denmark's renewable power sources generated 28,931GWh in 2015.  Annual output from the 2 reactors at South Texas Nuclear Generating Station is 22,179GWh.  In other words, 2 nuclear reactors operating at 91.7% capacity generated more than 76% as much electric power as all sources in Denmark.  If output from the other 2 nuclear reactors is included, 4 reactors generated more electric power than Denmark uses in a year.  Denmark also consumed 4,865GWh more electric power than it generated in 2015, but that's a minor detail for "renewables" advocates to ignore.

There are no wind or solar generating stations in the US that match the annual output of the average nuclear reactor in the US.  That is not a matter for principle, personal belief, or ideology.  That is cold hard numerology that does not care at all what I or anyone else happen to think or believe.


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